Glossary of electronics certification terms
Reference A-Z
130+ terms and acronyms from electronics certification, CE, FCC, RED and PTCRB, with concise definitions, practical context, and links to the site's pillar pages.
A-GPS / A-GNSS
Section titled “A-GPS / A-GNSS”A-GPS / A-GNSS, Assisted GPS / Assisted Global Navigation Satellite System. Technique where the cellular network supplies ephemeris, almanac and approximate position data to the device so it can lock onto satellites in seconds rather than minutes.
A-GNSS is critical for emergency services (E911 in the US, eCall in the EU) where Time-To-First-Fix must remain below a few tens of seconds even indoors. PTCRB certification includes A-GNSS performance tests against 3GPP TS 37.571. The control plane uses the SUPL or LPP protocols depending on the LTE/NR release. See PTCRB procedure.
ACLR, Adjacent Channel Leakage Ratio. Ratio between the power transmitted in the intended channel and the power that leaks into the adjacent channel, expressed in dB. A high ACLR (typically 33 dB or more for LTE user equipment, 45 dB for base stations under 3GPP TS 36.101) means the transmitter is "clean" and does not disturb neighbouring operators.
ACLR is measured during conducted RF tests on cellular modules (LTE, NR) and is one of the structuring criteria for PTCRB and GCF approval. A module that fails ACLR by 1 dB will be rejected even if every other metric is nominal, operators reuse spectrum at very close ranges and cannot tolerate spillover. See PTCRB tests and the RF transmitter chapter of 3GPP TS 36.521-1.
ACPR, Adjacent Channel Power Ratio. Ratio between the power transmitted in the wanted channel and the power that falls into a defined adjacent channel, expressed in dB or dBc. ACPR is the FCC and general wideband formulation of the same idea as ACLR: ACLR is the term 3GPP uses for LTE and NR user equipment, ACPR is the more generic spectrum analyser metric used in FCC type acceptance and in design bench work.
Both share the same measurement principle: integrate power in a reference bandwidth centred on the carrier and in a bandwidth centred on the adjacent channel, then take the ratio. ACPR is verified under 47 CFR §15.247 for 2.4 / 5 GHz wideband and under 3GPP TS 38.521-1 for NR. See ACLR for the LTE / NR specific limits and FCC standards.
AFC, Automated Frequency Coordination. FCC framework introduced in 2023 to authorise standard-power Wi-Fi 6E and Wi-Fi 7 access points in the U-NII-5 and U-NII-7 bands (5945-6425 and 6525-6875 MHz). An AFC device queries a certified geolocation database before transmitting and obtains the list of channels it can use without interfering with fixed incumbent links.
AFC replaces the static channel plan of historical Wi-Fi: power and bandwidth depend on geographical position and the time of day. The EU is preparing an equivalent mechanism for the 6 GHz upper band. See FCC standards and FCC 47 CFR §15.407 for the technical rules.
AFH, Adaptive Frequency Hopping. Mechanism specific to Bluetooth (Classic and BLE) that dynamically excludes channels affected by interference from the hop list. AFH allows Bluetooth and Wi-Fi to coexist in the same 2.4 GHz band without continuous mutual blocking.
AFH is mandatory under EN 300 328 for FHSS equipment and ensures the spectrum-efficient use required by Article 3.2 of the RED. During RED tests, AFH is verified by injecting a CW interferer and checking that the device under test removes the affected channels from its hop sequence within the time limits specified by the standard. See RED standards.
ANSI, American National Standards Institute. Private non-profit body that coordinates the U.S. standardisation system. ANSI does not write standards itself; it accredits Standards Development Organizations (SDOs) such as IEEE, ASTM or UL and represents the United States at ISO and IEC.
ANSI standards (e.g. ANSI C63.4, ANSI C63.10) underlie much of FCC equipment authorisation: ANSI C63.4 is the reference test method for unintentional radiators under Part 15 Subpart B, and ANSI C63.10 covers intentional radiators. They play a role equivalent to harmonised EN standards in the EU. See FCC standards.
Antenna factor
Section titled “Antenna factor”Antenna factor, AF. Calibration constant of a receive antenna, expressed in dB/m, that links the electric field strength incident on the antenna to the voltage delivered at its terminals: E (dBµV/m) = V (dBµV) + AF (dB/m) + cable losses (dB) − pre-amplifier gain (dB).
Antenna factor is given by the calibration certificate of the antenna, frequency point by frequency point (typically every 1 MHz from 30 MHz to 1 GHz, then horn antennas above 1 GHz). It must be issued by an ISO/IEC 17025 lab and traceable to CISPR 16-1-6. Without a valid AF, no spectrum analyser reading can be converted into a regulatory field strength: the AF is the link between the lab cable instrumentation and the limits of CISPR 32 / EN 55032 expressed in dBµV/m. See CE tests.
AoC, Authorisation of Conformity assessment body. Designation step in which a Member State formally authorises a candidate body to act as a Notified Body under a given EU directive or regulation, before notification to the European Commission via NANDO. AoC is the operational outcome of the designation procedure described in Regulation 765/2008 and Articles R17 to R20 of Decision 768/2008/EC.
The national authorising authority (in France, the Ministre de l'Industrie on advice from COFRAC) audits the candidate against ISO/IEC 17065, ISO/IEC 17021 or ISO/IEC 17025 depending on the module, then issues the AoC limited to a precise scope: directive, modules, product families, standards. Once notified, the body receives its four-digit NB number and may issue EU-type examination certificates. Manufacturers should always check the exact AoC scope in NANDO before contracting a Notified Body. See CE procedure.
APC, Adaptive Power Control. RED requirement that obliges a radio device to transmit at the minimum power needed to maintain link quality. APC reduces overall interference and extends battery life.
For Wi-Fi and Bluetooth, APC is mandatory above certain EIRP thresholds in 2.4 GHz and 5 GHz under EN 300 328 and EN 301 893. Testing verifies that the device actually lowers its power when the receiver reports a strong signal, with a measurement range of at least 6 dB. APC is to be distinguished from TPC (Transmit Power Control), which carries the same idea on the cellular side. See RED tests.
Approved Body
Section titled “Approved Body”Approved Body, UK conformity assessment body. Conformity assessment body designated by the United Kingdom and listed in the UKMCAB register to carry out third-party assessment under the UKCA regime, the exact counterpart of an EU Notified Body. It holds a four-digit number and its scope is limited to the UK Statutory Instruments it is designated for.
Because CE marking remains accepted in Great Britain for most products, an Approved Body is only involved when the manufacturer chooses the UKCA route and a module requires a third party. Always check the exact scope in the UKMCAB register before contracting. See the CE pillar.
ATEX, Atmosphères Explosibles, Directive 2014/34/EU. Governs equipment intended for use in explosive atmospheres (gas, dust) in the European Union. ATEX is independent of CE marking under LVD/EMC/RED but is cumulative with them: an intrinsically safe Bluetooth sensor for refinery use must satisfy RED + ATEX.
ATEX is structured in zones (0/1/2 for gas, 20/21/22 for dust) and equipment categories (M1, M2, 1, 2, 3). Conformity assessment involves a Notified Body for categories M1, M2, 1, and equipment of category 2 with electrical ignition source. Reference standards are the IEC 60079 series. ATEX is outside spilma's scope but is mentioned here because it is often confused with RED for industrial equipment. See CE scope.
Attestation
Section titled “Attestation”Attestation, Cryptographic proof of device state. Mechanism by which a device proves to a remote verifier that its hardware identity, firmware version or runtime measurements match an expected reference. Attestation answers the question "is the device I am talking to really the one I think, in the state I expect ?".
Three widely deployed variants illustrate the concept. The TPM Quote (ISO/IEC 11889) signs the current PCR values with an Attestation Identity Key. FIDO attestation lets a security key prove its model and certification level when registering. The Matter Device Attestation Certificate (DAC), chained to a Product Attestation Intermediate, proves a smart-home device was certified by the Connectivity Standards Alliance before commissioning. Attestation is mandatory under IEC 62443-4-2 CR 1.2 (software process and device identity) and underpins remote integrity checks in zero-trust deployments. See RED standards.
Average detector
Section titled “Average detector”Average detector, AV. CISPR weighting detector defined by CISPR 16-1-1 that returns the linear average of the envelope of the signal at the analyser input over the dwell time. For a pure carrier the AV reading equals the peak; for a low duty-cycle impulsive signal it drops sharply below the quasi-peak reading.
The average detector is mandatory on conducted emissions above 150 kHz (CISPR 32 Class A and B impose both QP and AV limits, with AV typically 13 dB below QP), and on radiated emissions above 1 GHz where CISPR 32 sets a peak limit and a stricter AV limit. AV is also the natural detector for switched-mode power converter spurs whose impulsive nature would otherwise pass under QP. See CE tests.
BLE, Bluetooth Low Energy. Variant of the Bluetooth standard introduced with version 4.0 (2010), optimised for battery operation. BLE shares the 2.4 GHz ISM band with Bluetooth Classic but uses a different physical layer (40 channels of 2 MHz instead of 79 of 1 MHz) and a stack based on GATT/ATT.
BLE is the dominant technology for IoT sensors, wearables and beacons. From the certification side, BLE devices fall under the RED in the EU (EN 300 328 and EN 301 489-17) and under FCC Part 15 Subpart C in the United States. The Bluetooth SIG also requires Bluetooth Qualification before the trademark can be used. See RED standards and FCC standards.
Blue Guide
Section titled “Blue Guide”Blue Guide, European Commission Blue Guide on the implementation of EU product rules. Reference document published by the Commission (last major update 2022) that explains how the New Legislative Framework (NLF) directives are applied: roles of the economic operators (manufacturer, authorised representative, importer, distributor), CE marking, declaration of conformity, Notified Bodies, market surveillance.
The Blue Guide has no legal force itself but is the authoritative interpretation when a directive is silent. It clarifies, for example, what "placing on the market" means, what an importer's obligations are for a non-EU brand, or how to reuse partial tests from a supplier. Essential reading before a first CE marking. See CE scope.
CE marking
Section titled “CE marking”CE marking, Conformité Européenne. Mark affixed by the manufacturer (not awarded by a third party) declaring that a product meets all applicable European directives and regulations. The CE marking is mandatory for products covered by NLF directives placed on the EU/EEA market.
CE marking is self-declaration in the vast majority of cases, radio, EMC, LVD, machinery, toys, etc. A Notified Body intervenes only for higher-risk products (medical devices class IIa+, lifts, pressure equipment) or when the manufacturer voluntarily chooses module B. CE is not a quality label and not a US/Asian "import authorisation". See the CE pillar and CE procedure.
CISPR, Comité International Spécial des Perturbations Radioélectriques. Special committee of the IEC that drafts international standards on EMC emissions. CISPR was founded in 1934 and groups national EMC laboratories and industrial federations.
CISPR standards (CISPR 11, 14, 15, 22, 32, 35...) are republished as EN standards by CENELEC, with possible European amendments (the A11 series). CISPR 32 on multimedia emissions is republished as EN 55032, the reference for EMC of audio, video and IT equipment. See CE standards.
CMIIT ID
Section titled “CMIIT ID”CMIIT ID, China Ministry of Industry and Information Technology ID. Radio approval identifier assigned by the Chinese SRRC to any transmitter placed on the market in China, in the form "CMIIT ID: YYYYXXXXXX". It attests radio type approval, separate from the CCC safety certification.
The CMIIT ID must be displayed legibly on the equipment or its screen (e-label), failing which the product cannot be sold or imported in China. It is the functional Chinese equivalent of the US FCC ID. See FCC procedure.
COFRAC
Section titled “COFRAC”COFRAC, Comité Français d'Accréditation. National French accreditation body, member of the European Accreditation (EA) network. COFRAC accredits test laboratories, calibration laboratories and certification bodies against ISO/IEC 17025 and ISO/IEC 17065.
In practical terms: a COFRAC-accredited EMC laboratory is recognised throughout the EU under the EA-MLA mutual agreement, then in countries that signed the ILAC arrangement (United States, Japan, Canada, etc.). Choosing a COFRAC-accredited laboratory for CE/RED tests secures the international recognition of the report. See CE procedure.
Common-mode current
Section titled “Common-mode current”Common-mode current, CM current, Icm. Current that flows in-phase on both conductors of a pair (or on every conductor of a cable bundle) and returns through the chassis or earth via stray capacitance. It is the primary source of radiation from cables: even a few microamps of common-mode current on a 1 m USB lead can blow the radiated emissions limit at 30-300 MHz.
Common-mode current is measured non-intrusively with a clamp-on current probe per CISPR 16-1-2, calibrated in dB(µA/V), the probe being part of the lab chain used in EN 61000-4-6 conducted RF immunity and as a diagnostic for radiated emissions failures. Mitigations: CM chokes at connectors, ground-plane continuity, shielded cables with 360° backshells, and short return paths under high-speed signals. See the radiated emissions guide.
Conducted emissions
Section titled “Conducted emissions”Conducted emissions, CE. EMC emissions test that measures the disturbance voltage injected by the EUT back into the mains in the 150 kHz - 30 MHz band. The mains lead is connected to a pair of LISNs defined by CISPR 16-1-2, the spectrum analyser reads the voltage at the LISN measurement port, and the result is compared to the limits of the applicable product standard.
For ITE/multimedia the limits come from CISPR 32 / EN 55032 with two classes: Class B (residential, around 66 dBµV QP at 150 kHz, dropping to 60 dBµV from 0.5 MHz upward) and Class A (industrial, 13 dB higher). Both QP and AV limits apply. The measurement chain is governed by CISPR 16-2-1 and the labs typically use a quasi-peak pre-scan followed by AV on suspect peaks. Switched-mode supplies are the usual suspect. See CE tests.
Conflict minerals
Section titled “Conflict minerals”Conflict minerals, 3TG and cobalt sourced from conflict-affected and high-risk areas (CAHRA). Tin, tantalum, tungsten and gold ("3TG"), plus increasingly cobalt and mica, whose extraction may finance armed groups or be linked to serious human-rights abuses.
Two main regulatory regimes apply. In the United States, Dodd-Frank 1502 requires SEC-registered issuers to perform a Reasonable Country of Origin Inquiry on 3TG from the DRC and adjoining countries and to publish a Conflict Minerals Report. In the European Union, Reg (EU) 2017/821 imposes due-diligence obligations on importers of 3TG above defined volume thresholds, aligned with the OECD Due Diligence Guidance. Supply-chain reporting commonly uses the CMRT (3TG) and EMRT (cobalt, mica) templates maintained by the Responsible Minerals Initiative (RMI), populated with smelter and refiner data from the RMAP audit programme. See Conflict minerals guide.
CSI, Channel State Information. Set of measurements that the UE reports to the base station to describe the downlink radio channel: CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indicator) and, in 5G NR, CRI (CSI-RS Resource Indicator) and Layer Indicator. CSI feeds the link adaptation loop, the MCS selection and the precoder choice on the gNB side.
CSI reporting is specified by 3GPP TS 38.214 for NR (and TS 36.213 for LTE), with periodic, semi-persistent and aperiodic modes carried on PUCCH or PUSCH. CSI accuracy directly impacts throughput and is verified in the performance test series TS 38.521-3 / TS 36.521-3 (CSI reporting test cases). In massive MIMO deployments the CSI codebooks (Type I, Type II) determine how well the gNB can exploit spatial multiplexing. See PTCRB tests.
CSMS, Cyber Security Management System. Cybersecurity management system that a vehicle manufacturer must establish and have certified under UNECE R155 to obtain vehicle type approval. The CSMS covers cyber risk management across the whole life cycle: design, production and the post-production phase with monitoring and incident response.
ISO/SAE 21434 provides the engineering framework used as evidence of CSMS conformity. Without a valid CSMS certificate issued by the type-approval authority, no new vehicle can be homologated in countries applying R155. See the CE pillar.
CTIA, Cellular Telecommunications and Internet Association. American industry association that runs the Certification Program for cellular and Wi-Fi devices on US operator networks (AT&T, Verizon, T-Mobile). CTIA publishes test plans (OTA RF performance, battery life, Wi-Fi performance) that operators reuse in their device requirements.
The CTIA "OTA Test Plan" is the de facto reference for measuring TRP and TIS of cellular devices, even outside the United States, operators worldwide cite it. CTIA certification overlaps with PTCRB (run by the same association) but covers different aspects: PTCRB targets 3GPP RF conformance, CTIA covers performance and operator-level requirements. See PTCRB pillar.
CVD, Coordinated Vulnerability Disclosure. Process by which a security researcher reports a vulnerability to a vendor, the vendor develops a fix, and both parties agree on a public disclosure timeline. CVD replaces the older "responsible disclosure" wording and aims to balance the user's right to know with the time needed to deploy a patch.
The reference framework is ISO/IEC 29147 (vulnerability disclosure) paired with ISO/IEC 30111 (vulnerability handling processes). CERT/CC at Carnegie Mellon defines a 45-day default embargo, extendable by mutual agreement. Under EN 18031-1 and the Cyber Resilience Act, every connected product must publish a security.txt or equivalent contact channel and operate a documented CVD policy. Absence of a working CVD channel is a non-conformity flagged during RED Article 3.3(d) assessment. See RED standards and EN 303 645 IoT cybersecurity guide.
DFS, Dynamic Frequency Selection. Mechanism that obliges Wi-Fi devices in the 5 GHz band (specifically sub-bands 5250-5350 and 5470-5725 MHz) to detect weather and aviation radars and to vacate the channel within a defined time (typically 10 seconds detection + 60 seconds non-occupancy).
DFS is mandatory under EN 301 893 in the EU and under FCC 47 CFR §15.407 in the US. Testing involves injecting reference radar pulse patterns (DFS waveforms) and verifying the channel change. DFS is one of the longest and most failure-prone tests in RED radio test campaigns. See RED tests.
DoC, EU Declaration of Conformity. Single document signed by the manufacturer in which it declares that the product meets all applicable directives. The DoC is the legally enforceable document that accompanies CE marking, losing or omitting it equates to the absence of CE.
Mandatory content (Annex IV of the RED, Annex IV of the EMC Directive): identification of the product, name of the manufacturer, list of applied directives, list of applied harmonised standards with exact references (year + amendments), date and signature. The DoC must remain available for ten years after the last unit is placed on the market. See the CE technical file for templates.
DoP, Declaration of Performance. Document required by Regulation 305/2011 (Construction Products Regulation, CPR) by which the manufacturer of a construction product declares the performance of the essential characteristics covered by a harmonised standard or a European Assessment Document. The DoP is the CPR analog of the EU Declaration of Conformity used under the other NLF directives, but the regime differs: CPR declares performance levels, not conformity to essential requirements.
The DoP is mandatory before CE marking of any covered construction product, including cables under EN 50575 (reaction to fire classes Aca to Fca). Mandatory content is fixed by Annex III of CPR 305/2011: unique product code, intended use, manufacturer, AVCP system (1+, 1, 2+, 3, 4), notified body number where applicable, declared performance per characteristic with the test method reference. A copy must be supplied with each product (paper or electronic, Regulation 157/2014). See CPR guide.
DPP, Digital Product Passport. Machine-readable record of product attributes mandated under Reg (EU) 2024/1781 ESPR, accessible via a QR code or other data carrier affixed to the product.
The DPP centralises information on materials and substances of concern, repairability, disassembly instructions, recycled content, carbon footprint and key supply-chain actors. It is intended to enable verification by market surveillance, repair operators, recyclers and end users along the entire value chain. ESPR introduces the DPP progressively, by product group, through delegated acts: batteries (already covered by Reg (EU) 2023/1542), textiles, electronics, construction products and steel are among the early waves. Data carriers and exchange protocols rely on standardisation work led by CEN-CENELEC JTC 24. See ESPR ecodesign guide and CE scope.
DSSS, Direct Sequence Spread Spectrum. Spread spectrum technique used by 802.11b Wi-Fi (and previously by GPS L1 C/A): the data signal is multiplied by a higher-rate pseudo-random sequence (chip rate), spreading the spectrum and improving robustness against narrowband interference.
DSSS is one of the modulation modes recognised by EN 300 328 in the 2.4 GHz band, separate from FHSS, with its own emission limits and a maximum EIRP of 100 mW. DSSS is becoming rare in Wi-Fi (replaced by OFDM since 802.11g/n/ac) but still serves in some industrial protocols (ZigBee/802.15.4, Z-Wave). See RED standards.
Dwell time
Section titled “Dwell time”Dwell time, Per-hop occupancy time in a FHSS system. Time the transmitter spends on a single hop frequency before moving to the next one in its pseudo-random sequence. Dwell time is one of the structural parameters that distinguishes a compliant FHSS transmitter from a wideband one.
Under EN 300 328 in 2.4 GHz, the average dwell time per channel and per 100 ms is capped so that energy is spread across the hop list rather than concentrated on a few channels. The FCC counterpart 47 CFR §15.247 caps the dwell time per channel within a 30-second window and requires use of a minimum number of hopping channels. Bluetooth Classic (1600 hops per second over 79 channels of 1 MHz) and Bluetooth LE with AFH fit naturally inside these rules. See RED standards.
EAA, European Accessibility Act, Directive (EU) 2019/882 on accessibility requirements for products and services. It imposes, from 28 June 2025, accessibility requirements on a list of products including consumer terminals, e-readers, payment terminals and self-service computing equipment.
For electronics, the EAA touches hardware and software interfaces: multisensory feedback, compatibility with assistive technologies, legible labelling. Presumption of conformity rests on the harmonised standard EN 301 549. The EAA adds to the existing CE marking without replacing it. See CE scope.
EAS, Equipment Authorization System. FCC public database (eas.fcc.gov, replacing the historical OET database) that lists every device certified under Part 15, Part 22, Part 24, Part 27, etc. Each entry contains the FCC ID, the manufacturer, the test reports, the photographs and the user manual.
EAS is the FCC counterpart of "type certification": searching for an FCC ID gives access to the exact equipment configuration certified, the bands, the maximum power and the test report. It is also the source for confirming whether an integrator's modular approval applies to a given Wi-Fi or cellular module. See FCC procedure.
eCall: European emergency call system mandatory in all new M1 and N1 vehicles approved since 31 March 2018 (Regulation (EU) 2015/758). After a major collision detected by the airbag sensors, eCall automatically dials 112 and transmits a Minimum Set of Data (MSD): geolocation, vehicle identification, direction of travel, occupant count.
eCall combines a GNSS receiver and a 2G/4G cellular modem and falls under RED + automotive type approval (ECE R10). Tests include 112-eCall transmission and reception with synthetic crash scenarios. The In-Vehicle System (IVS) is now migrating to 4G (NG eCall, EN 17240) as 2G/3G networks are switched off. See RED scope.
ECE R10 / e-mark
Section titled “ECE R10 / e-mark”ECE R10 / e-mark, UN Regulation No 10 on the electromagnetic compatibility of vehicles. UNECE regulation that sets the EMC requirements for road vehicles and their electrical or electronic sub-assemblies, a precondition of automotive type approval. A compliant component receives the e-mark (a lower-case "e" in a rectangle followed by the approving country number), distinct from the upper-case E-mark of classic ECE regulations.
Any radio or electronic module intended to be fitted in a vehicle (TCU, tracker, eCall) must meet ECE R10 on top of RED or FCC. Testing reuses CISPR principles applied to the vehicle environment (CISPR 25, CISPR 12) with their own limits. See CE tests.
Economic operator
Section titled “Economic operator”Economic operator: Collective term used by the New Legislative Framework for the four roles in the EU product supply chain: manufacturer, authorised representative, importer and distributor. Defined by Article 2 of Regulation 765/2008 and Annex I of Decision 768/2008/EC, reiterated by every NLF directive (RED, EMC, LVD, Machinery, Toys, PPE, Construction Products).
Each role carries distinct obligations. The manufacturer designs the product, draws up the technical file, signs the DoC and affixes the CE marking. The authorised representative is the mandated EU-established person who acts for a non-EU manufacturer on market access tasks. The importer places a product from a third country on the EU market and verifies the manufacturer's documentation. The distributor makes the product available on the market and must check labelling and instructions. Regulation 2019/1020 added traceability obligations (Article 4) for products sold online without an EU manufacturer or importer. See CE scope.
EFT, Electrical Fast Transient, also called Burst. EMC immunity test specified in EN 61000-4-4. Reproduces the fast pulse bursts caused by relay or contactor switching: groups of 75 pulses at 5 or 100 kHz, with amplitudes from 0.5 to 4 kV applied capacitively to power and signal lines.
The EFT is one of the most stringent immunity tests because it directly couples to PCB tracks via capacitive crosstalk. Critical countermeasures include CM/DM filtering at the connectors, gas discharge or TVS protection, and clean ground separation. Required by EN 55035 and EN 61000-6-1 series. See CE tests.
EIRP, Effective Isotropic Radiated Power. Power that an isotropic antenna (radiating equally in all directions) would have to emit to produce the same field strength as the device under test in the direction of maximum gain. EIRP = Pconducted + Gantenna − Lcable (in dBm and dBi).
EIRP is the regulatory unit for radio in the EU and the US: 20 dBm EIRP in 2.4 GHz (EU), 23 dBm in 5150-5250 MHz, 30 dBm in 5470-5725 MHz, 36 dBm in WBAN 2.4 GHz under FCC. Measured via spectrum analyser + calibrated antenna in an anechoic chamber. See RED standards and EN 300 328.
EMC, Electromagnetic Compatibility. Discipline that ensures equipment does not generate excessive electromagnetic disturbances (emissions) and tolerates the disturbances present in its environment (immunity). EMC is covered in the EU by Directive 2014/30/EU.
EMC tests split into two families: emissions (radiated 30 MHz - 1 GHz on a 10 m or 3 m site, conducted 150 kHz - 30 MHz with LISN) and immunity (ESD, EFT, surge, RF radiated, RF conducted, magnetic, dips). Each product family has a dedicated harmonised standard (EN 55032, EN 55014-1, EN 55011...). See CE tests.
EMV
For a payment terminal or NFC reader, EMV
EN 301 549
Section titled “EN 301 549”EN 301 549, accessibility requirements for ICT products and services. European harmonised standard that translates digital accessibility obligations into technical requirements, cited by the Web Accessibility Directive (EU) 2016/2102 and by the European Accessibility Act (EU) 2019/882. It covers hardware, software, web content and documentation.
For an electronic product with a user interface, EN 301 549 sets criteria on contrast, multisensory feedback, keyboard compatibility and support for assistive technologies. Applying it correctly opens a presumption of conformity with the accessibility requirements of the EAA. See CE scope.
ESD, Electrostatic Discharge. Sudden transfer of static charge between two bodies of different potentials. EMC immunity test under EN 61000-4-2: ±2 / ±4 / ±6 / ±8 kV contact discharge, ±2 / ±4 / ±8 / ±15 kV air discharge, applied to all accessible surfaces and connectors.
ESD is the most discriminating immunity test for consumer products: a poorly designed plastic enclosure, an exposed USB connector or insufficient mass return systematically lead to system crash or product reset. Recommended countermeasures: ESD diode arrays at connectors, ground planes, and creepage/clearance distances. Required by EN 55035, EN 61000-6-1 and the IEC 61000-6-x series. See CE tests.
eSIM, Embedded Subscriber Identity Module. Programmable SIM card directly soldered to the device PCB, conforming to GSMA standards SGP.02 (M2M) and SGP.22 (consumer). The eSIM allows operator change Over-The-Air without physically replacing the card.
eSIM imposes specific certification: GSMA SGP.24 / SGP.25 (Subscription Manager) and full PTCRB on the host module. eUICC profiles must be GSMA-certified and downloaded via SM-DP+ servers approved by SAS-SM. Cellular IoT manufacturers must arbitrate between integrated eSIM (industrial life, lower BOM) and removable SIM (operator flexibility). See PTCRB scope.
ESPR, Ecodesign for Sustainable Products Regulation, Reg (EU) 2024/1781. Replaces and broadens the 2009 Ecodesign Directive 2009/125/EC, extending ecodesign requirements from energy-related products to nearly all physical goods placed on the EU market.
ESPR empowers the Commission to set, via delegated acts, performance and information requirements per product group: durability, reliability, reusability, upgradability, reparability, presence of substances of concern, energy and resource efficiency, recycled content, remanufacturing, recyclability and carbon footprint. Each delegated act may also mandate a Digital Product Passport, prohibit the destruction of unsold consumer goods (already binding for textiles and footwear) and define minimum thresholds. The first ESPR Working Plan (2025-2030) covers iron and steel, aluminium, textiles, furniture, tyres, mattresses and certain electronics. See ESPR ecodesign guide and CE scope.
ETSI, European Telecommunications Standards Institute. ESO (European Standards Organisation) based in Sophia Antipolis, France, founded in 1988. ETSI drafts radio and telecommunications standards on Commission mandate (RED) but also publishes private technical specifications (TS), industry reports (TR) and group specifications (GS).
ETSI standards carry the "EN 3xx xxx" prefix when harmonised (e.g. EN 300 328, EN 301 489). ETSI also produces 3GPP standards re-published as TS XXX-XXX series. Standards are versioned Vx.y.z with publication date in parentheses, a notation that must appear exactly in the DoC. See CE standards.
EUT, Equipment Under Test. The device, the system or the assembly being tested. The terminology comes from EMC and radio testing standards (CISPR, ETSI, 3GPP) and recurs in all test reports.
The EUT must be configured in typical operation: maximum power for emissions, worst-case modulation for spectrum tests, all interfaces active. The configuration of the EUT is documented in the test plan and reproduced identically by the laboratory. A change in EUT (firmware, peripherals, position of the antenna) generally invalidates the previous report and triggers a delta retest. See CE technical file.
EVM, Error Vector Magnitude. Distance, in the IQ plane, between each received constellation point and the ideal point it should occupy, normalised to the RMS magnitude of the constellation and expressed as a percentage or in dB. EVM is the headline measure of modulation accuracy on the transmit side.
EVM is a 3GPP transmitter requirement for LTE uplink (typically 17.5% for QPSK, 12.5% for 16QAM, 8% for 64QAM under 3GPP TS 36.521-1) and for NR. A bad EVM usually points at PA non-linearity, IQ imbalance, phase noise or thermal compression. EVM is also a sensitive indicator during board bring-up because it captures distortions that single-tone power measurements would miss. See PTCRB tests.
FCC ID
Section titled “FCC ID”FCC ID: Unique identifier assigned by the FCC to every radio device certified under Part 15C, Part 22, Part 24, etc. The FCC ID is structured as GranteeCode + ProductCode (e.g. BCG-E3091A for an iPhone). The Grantee Code (3 to 5 characters) is assigned to the manufacturer, the Product Code is freely chosen.
The FCC ID must appear visibly on the product or on its electronic label (e-label, allowed since the FCC Modernization Order of 2017). Searching for an FCC ID on eas.fcc.gov returns the full file: test report, photographs, internal block diagram, antenna data sheet. A Bluetooth or cellular module embedded under modular approval keeps its own FCC ID; the host need not redo the test. See FCC procedure.
FHSS, Frequency Hopping Spread Spectrum. Spread spectrum technique where the transmitter rapidly changes carrier frequency on a pseudo-random sequence shared with the receiver. Bluetooth Classic (1600 hops/s on 79 channels of 1 MHz) and Bluetooth LE (with AFH) are FHSS systems.
Under EN 300 328, FHSS systems benefit from a separate set of rules to DSSS/OFDM: minimum hop length, dwell time, channel spacing. The same applies under FCC Part 15.247. The FHSS rules historically allow more EIRP than DSSS in some bands, but the gap has narrowed since 2017 in 2.4 GHz. See RED standards.
Frequency offset
Section titled “Frequency offset”Frequency offset, Carrier frequency error. Difference between the carrier frequency actually transmitted by the device and the nominal frequency defined by the channel raster, expressed in Hz or in parts per million (ppm) of the carrier.
For a 3GPP UE, the frequency offset requirement under 3GPP TS 36.521-1 and 3GPP TS 38.521-1 is typically around 0.1 ppm relative to the serving cell after the device has locked. At 2 GHz that is roughly 200 Hz. The device locks its TCXO or VCTCXO onto the downlink signal to meet this requirement; an uncompensated drift over temperature is a frequent cause of failure in the operating temperature corner tests. The same metric is checked for Bluetooth and Wi-Fi, with looser tolerances. See RED tests.
GCF, Global Certification Forum. International certification scheme for cellular devices (LTE, NR, IoT NB-IoT/LTE-M), created in 1999 by mobile operators and manufacturers. GCF certifies devices against 3GPP specifications and against operator-specific test cases.
GCF largely overlaps with PTCRB (same 3GPP scope) but has a broader operator base (Europe, Asia, parts of Latin America) where PTCRB focuses on the United States. Many manufacturers do both certifications in parallel; tests are mutualised and the lead time is split. GCF Field Trials extend testing to real network conditions. See PTCRB pillar and PTCRB standards.
GCF Field Trial
Section titled “GCF Field Trial”GCF Field Trial, Global Certification Forum Field Trial. Real-network test phase within the GCF certification scheme that complements the lab conformance work done against 3GPP test specifications. Field Trials are run on commercial operator networks selected by GCF, with the device under test exposed to real radio conditions, real cells, real handovers and real neighbour lists.
A GCF campaign is split into two parts: conformance tests in lab (RF, RRM, protocol, against 3GPP TS 36.521-1 and 3GPP TS 38.521-1) and Field Trials documented in GSMA TS.34. Field Trials catch what the lab cannot: interference from neighbour cells, mobility between coverage zones, attach failures on specific PLMN configurations. A device that passes lab conformance can still fail Field Trials and lose the GCF declaration. See PTCRB pillar and PTCRB standards.
gNB, next-generation NodeB. 5G base station defined by 3GPP that terminates the NR air interface towards the UE and connects either to the 5G Core (5GC) in standalone mode or to an LTE eNB in non-standalone mode (EN-DC). The gNB handles scheduling, beam management, HARQ retransmissions and radio resource control on the NR side.
The gNB architecture is described in 3GPP TS 38.300, and can be split into a Central Unit (gNB-CU) and one or more Distributed Units (gNB-DU) connected by the F1 interface. For UE certification, the gNB is emulated by the test system: PTCRB and GCF labs use a network simulator that plays the gNB role to exercise the UE under 3GPP TS 38.521-1 conditions. See PTCRB procedure.
GSMA, GSM Association. Industry association representing more than 750 mobile operators and around 400 ecosystem partners. GSMA publishes major specifications around the SIM (eUICC SGP.02/22), security (SAS), IoT (IoT SAFE), Rich Communications Services (RCS) and operator interoperability.
GSMA does not certify devices directly but its specifications underlie many other schemes: eSIM falls under SGP.24 / SGP.25, the SM-DP+ servers must hold SAS-SM, network testing relies on TS.34. The IMEI Type Allocation Code (TAC) is administered by GSMA. See PTCRB pillar.
Harmonised standard
Section titled “Harmonised standard”Harmonised standard: Technical standard drafted by CEN, CENELEC or ETSI on European Commission mandate, whose reference is published in the Official Journal of the European Union (OJEU, C series). Applying a harmonised standard correctly grants the manufacturer a presumption of conformity to the essential requirements of the corresponding directive.
A harmonised standard is never mandatory, the manufacturer may always prove conformity by other means, but losing presumption shifts the burden of proof to the manufacturer in the event of audit. The harmonised version is identified by its OJEU publication, not just by the EN reference: the same EN may exist outside the OJEU and not grant presumption. See CE standards.
Hop length
Section titled “Hop length”Hop length, Frequency separation between consecutive hops in a FHSS system. Distance, in Hz, between the carrier frequency of one hop and the carrier frequency of the next hop in the pseudo-random sequence, together with the total number of distinct frequencies used. Hop length is what makes the hopping pattern actually spread spectrum rather than a slow retune.
EN 300 328 requires a minimum hop length and a minimum number of hopping frequencies for FHSS in 2.4 GHz; the FCC equivalent 47 CFR §15.247 uses a minimum channel separation and a minimum hop list size. Bluetooth Classic satisfies both by hopping 1 MHz at a time across 79 channels, and BLE in connected mode uses 37 data channels with AFH. A pattern that revisits too few frequencies or hops too narrowly will fail the RED test even if the dwell time is correct. See RED standards.
ICNIRP
Section titled “ICNIRP”ICNIRP, International Commission on Non-Ionizing Radiation Protection. International non-governmental scientific commission that issues general public and worker exposure guidelines for electromagnetic fields from 0 Hz to 300 GHz. ICNIRP 1998 (general guidelines) and ICNIRP 2020 (RF 100 kHz - 300 GHz) are the references.
The EU has transposed the ICNIRP limits into Recommendation 1999/519/EC (general public) and Directive 2013/35/EU (workers). ICNIRP limits are the basis for the SAR and MPE tests required by RED (Article 3.1(a)) and FCC 47 CFR §1.1310. They underlie the protection requirements verified by EN 62311 and EN 50360. See RED standards.
IEC, International Electrotechnical Commission. International organisation founded in 1906, based in Geneva, that drafts standards for everything electrical, electronic and related technologies. IEC publishes around 10,000 standards and is structured into Technical Committees (TC, SC).
IEC standards are reused as EN by CENELEC (with possible European amendments) and as ANSI by the United States. IEC 62368-1 on AV/IT safety, IEC 61010-1 on measuring equipment safety and the IEC 60601 series on medical devices are pillars of CE marking. IEC also runs the IECEE / CB Scheme that mutualises safety reports between member countries. See CE standards.
ILAC, International Laboratory Accreditation Cooperation. International organisation that coordinates national laboratory accreditation bodies (COFRAC for France, UKAS for the United Kingdom, A2LA for the United States, JAB for Japan...) and signs Mutual Recognition Arrangements (MRA).
In practical terms: an ILAC-MRA accredited test report under ISO/IEC 17025 is mutually recognised by every signatory country, which avoids redoing the test in the destination market. Critical for export, a CE test campaign in a COFRAC-accredited lab is recognised by US authorities and Asian regulators with significant savings. See CE procedure.
IMEI, International Mobile Equipment Identity. Unique 15-digit identifier (16 with check digit) assigned to every cellular device (GSM, UMTS, LTE, NR). Structure: TAC (8 digits) + SNR (6 digits) + CD (1 digit). The TAC (Type Allocation Code) is allocated by GSMA and identifies the model.
The IMEI must be displayable by the user (dialling *#06#), permanently affixed to the device or e-labelled, and traceable in the manufacturer's database. Operators use IMEI to blacklist stolen devices via the CEIR registry. The IMEISV (16 digits) adds software version information. Obtaining a TAC is a mandatory step before PTCRB submission. See PTCRB procedure.
IMS, IP Multimedia Subsystem. 3GPP architecture (TS 23.228) introduced in Release 5 that supports voice, video and messaging services over IP. IMS is the technical foundation of VoLTE (Voice over LTE), VoWi-Fi and VoNR (Voice over NR).
A modern cellular device must implement an IMS client to make voice calls on a 4G or 5G network, historical 2G/3G circuit-switched voice is going away as networks shut down. PTCRB tests IMS conformance against 3GPP TS 34.229 and operator-specific test cases (AT&T NID, Verizon OAT). See PTCRB tests.
IoT, Internet of Things. Generic term covering devices connected to the internet beyond traditional computers and phones: sensors, actuators, gateways, wearables, industrial equipment. The IoT is not a specific technology but an architectural family combining radio (BLE, Wi-Fi, LoRaWAN, NB-IoT, LTE-M), cloud, embedded software and security.
From the certification side, IoT does not have a "dedicated" directive, it falls under the existing rules: RED for radio, EMC, LVD if mains-powered, cybersecurity since 1 August 2025 under Delegated Regulation (EU) 2022/30 (Articles 3.3(d)(e)(f) of the RED). The Cyber Resilience Act (CRA) extends the requirements to all "products with digital elements" from 2027. See RED scope.
ISM bands
Section titled “ISM bands”ISM bands, Industrial, Scientific and Medical. Frequency bands historically reserved for industrial, scientific and medical applications generating intentional or unintentional radio emissions. ITU-R standardised the ISM bands at the international level: 6.78 MHz, 13.56 MHz (NFC, RFID), 27.12 MHz, 40.68 MHz, 433 MHz (Europe), 915 MHz (Americas), 2.45 GHz (Wi-Fi, Bluetooth, microwave), 5.8 GHz, 24 GHz.
ISM bands are "licence-free" for general use: a Wi-Fi or Bluetooth device can transmit without operator permit, provided it respects EIRP limits and rules (LBT, AFH, duty cycle). Equipment used outside ISM bands (e.g. SRD 868 MHz in Europe) is regulated separately. See RED standards.
ISO/IEC 17025
Section titled “ISO/IEC 17025”ISO/IEC 17025: International standard "General requirements for the competence of testing and calibration laboratories". The certification standard for test laboratories worldwide. A 17025-accredited laboratory has its competence audited every 18 to 24 months by a national accreditation body (COFRAC, UKAS, A2LA...).
For CE, RED, FCC and PTCRB, using a 17025-accredited laboratory is de facto mandatory: PTCRB and FCC require it explicitly; CE/RED do not require it formally but the absence of accreditation drastically weakens the report's value in a market surveillance audit. The accreditation scope of the laboratory (specific tests and standards) must be checked before signing. See CE procedure.
ISO/SAE 21434
Section titled “ISO/SAE 21434”ISO/SAE 21434, Road vehicles, cybersecurity engineering. Joint ISO and SAE standard that defines cybersecurity engineering for automotive electronic systems across the whole life cycle, from design to decommissioning. It introduces the TARA analysis and structures cyber risk management activities at component and vehicle level.
ISO/SAE 21434 is the recognised technical framework for demonstrating conformity with UNECE R155 and feeding the CSMS required for type approval. It is the automotive counterpart of IEC 62443-4-1 in the industrial world. See the CE pillar.
KDB, Knowledge Database. FCC publication system (apps.fcc.gov/oetcf/kdb) where the Office of Engineering and Technology issues clarifications, additional procedures and interpretations of the rules. Each KDB Publication is identified by a 6-digit number (e.g. 996369 for E-label, 447498 for general SAR).
KDBs are not regulations strictly speaking but TCBs and labs apply them as if they were: a KDB published on a specific point (modular approval procedure, SAR for tablets, EIRP measurement methodology in 6 GHz) becomes the operational reference. Monitoring relevant KDB updates is part of regulatory watch for any FCC project. See FCC standards.
Key ladder
Section titled “Key ladder”Key ladder, hardware-anchored key derivation chain. Sequence of cryptographic operations in which a Root Key, burned into hardware fuses and never exposed to software, derives an intermediate key, which itself derives a working key for the application. Each step runs inside a dedicated crypto engine, so upper-level keys never appear in CPU registers or RAM.
Key ladders originated in pay-TV conditional access and now underpin device-bound data protection in TEE-equipped SoCs (Arm TrustZone, RISC-V Keystone). A related primitive is TPM PCR sealing: a key is "sealed" to a set of Platform Configuration Register values and the TPM only unwraps it when boot measurements match. This guarantees that disk-encryption keys are released only on a verified-boot system. Key ladders are referenced by FIPS 140-3 Level 2+ for key encapsulation and by IEC 62443-4-2 CR 4.3. See RED standards.
LBT, Listen Before Talk. Coexistence mechanism imposed by EN 300 328 (2.4 GHz) and EN 301 893 (5 GHz Wi-Fi): the transmitter must listen to the channel and ensure it is free (energy below a threshold of -73 dBm in 5 GHz over a 20 MHz channel) for a minimum time (typically 18 µs + random backoff) before transmitting.
LBT applies to wideband digital systems (Wi-Fi, recent BLE). It replaces or supplements duty cycle for narrowband SRD on EN 300 220 in the 868 MHz band. Testing under EN 300 328 verifies that the device under test actually delays its transmission when a synthetic signal is injected at -73 dBm. See RED tests.
LISN, Line Impedance Stabilization Network. EMC tool that presents a controlled 50 Ω impedance between the EUT mains cable and the spectrum analyser, while filtering the mains supply (50 Hz) from the conducted measurement (150 kHz - 30 MHz). Defined by CISPR 16-1-2.
Two LISNs are placed on phase and neutral (or all conductors of a 3-phase line) of the device. The conducted emissions test reads the voltage at the measurement port and compares it to the limits of the applicable standard (CISPR 32 Class A or B for example). Without a LISN, the measurement of conducted emissions has no reproducible reference. See CE tests.
LVD, Low Voltage Directive 2014/35/EU. Covers electrical equipment operating between 50 V and 1000 V AC, or 75 V and 1500 V DC. The LVD imposes essential safety requirements: electrical insulation, protection against electric shock, abnormal heating, fire, mechanical and chemical hazards.
LVD is one of the three core CE directives for electronics (with EMC and RED). It is self-declaration without Notified Body. The applicable harmonised standards are EN 62368-1 (audio/video/IT), EN 61010-1 (measurement equipment), EN 60335-1 (household appliances), EN 60601-1 (medical electrical devices). A product powered exclusively below 50 V AC / 75 V DC (e.g. a USB sensor) is outside the LVD scope but its mains adapter falls within. See CE scope.
Modulation accuracy
Section titled “Modulation accuracy”Modulation accuracy, Constellation conformance of the transmitted signal. Family of measurements that quantify how close the transmitted symbols sit to the ideal points of the modulation scheme. Modulation accuracy is most often reported as EVM (in percent or in dB) but it also includes related metrics such as magnitude error, phase error and origin offset.
Modulation accuracy is a mandatory transmitter requirement under 3GPP TS 36.521-1 and 3GPP TS 38.521-1, and is also assessed for Bluetooth (DEVM, in EN 300 328 tests) and Wi-Fi. The metric drives the receiver demodulation margin: a transmitter that hits its EVM target leaves the receiver enough headroom to recover symbols at the cell edge. On the bench, modulation accuracy is the single number that most reliably reflects PA linearity and IQ calibration quality. See PTCRB tests.
Modules A through H
Section titled “Modules A through H”Modules A through H: Conformity assessment modules defined in Decision 768/2008/EC, the legal toolbox the EU directives draw from. Each directive lists the modules applicable to its products and the manufacturer chooses among them.
- Module A: Internal production control (self-declaration). Most common for CE EMC/RED/LVD.
- Module B: EU-type examination by a Notified Body. Often combined with C, D, E or F.
- Module C: Conformity to type based on internal production control.
- Module D: Conformity to type based on QA of the production process.
- Module E: Conformity to type based on product QA.
- Module F: Conformity to type based on product verification.
- Module G: Conformity based on unit verification (rare, one-off products).
- Module H: Full QA system.
RED for example allows modules A, B+C, H. See CE procedure.
MPE, Maximum Permissible Exposure. FCC counterpart of European SAR for "far-field" exposures, i.e. devices radiating at a distance > 20 cm from the body. Expressed in mW/cm² of incident power flux density and in V/m of electric field. Limits defined in 47 CFR §1.1310.
For a Wi-Fi access point on a ceiling or a base station, the FCC accepts an MPE calculation from EIRP and distance instead of a SAR measurement. For tablets and phones carried close to the body, SAR remains mandatory. The European equivalent for far-field is EN 62311 on EMF exposure up to 300 GHz. See FCC standards.
MRA, Mutual Recognition Agreement. International agreement between two regulators (or accreditation bodies) under which test reports and conformity assessment certificates issued in one country are recognised by the other. The EU has MRAs with the United States (1998), Canada, Japan, Australia, New Zealand, Switzerland.
The EU-US MRA specifically allows a Notified Body to certify telecom equipment for the US market (and an FCC TCB to certify for the EU market for the telecom annex). On test reports, the ILAC-MRA between accreditation bodies plays an equivalent role for ISO/IEC 17025 reports. MRAs are the lever for reducing dual EU/US certification costs. See EU-US dual certification.
NB, Notified Body. Independent body designated by a Member State and notified to the European Commission to carry out conformity assessment tasks under a New Approach directive. NBs hold a unique four-digit number (e.g. LCIE 0081, TÜV Süd 0123).
The NB is mandatory for higher-risk products (medical devices class IIa+, lifts, pressure equipment), or when the manufacturer chooses module B (EU-type examination). For RED and EMC, NB use is voluntary, the manufacturer may resort to it to consolidate its dossier on an emerging product. The list of notified bodies per directive is on the NANDO database. See CE procedure.
NB number
Section titled “NB number”NB number, Notified Body identification number. Four-digit identifier assigned by the European Commission to each Notified Body upon notification under an NLF directive. Examples: 0081 LCIE (France), 0123 TÜV Süd (Germany), 0344 DEKRA (Netherlands), 0359 Eurofins E&E (France).
The NB number is the public key into the NANDO database (Commission portal New Approach Notified and Designated Organisations) where the exact scope per directive, module and product family is published. It must be affixed next to the CE marking when the NB has intervened in a production-phase module (D, E, F, H), per Decision 768/2008/EC Annex II. A wrong or expired NB number on the CE label is a frequent market surveillance finding. The number on a certificate must always match the issuing body and the scope notified at the date of signature. See CE technical file.
NFC, Near Field Communication. Inductive communication technology in the 13.56 MHz ISM band, with a typical range of less than 10 cm. NFC is standardised by ISO/IEC 14443 (proximity cards) and ISO/IEC 18092 (NFCIP-1). Dominant applications: contactless payment, transport, identification, BLE pairing.
NFC equipment is regulated as SRD: EN 303 098 in the EU (and the broader EN 300 330 for inductive systems 9 kHz - 30 MHz) and FCC Part 15 Subpart C in the US. Antenna emissions are measured in magnetic field (dBµA/m) and not in electric field, this is the major difference compared with VHF/UHF radio testing. See RED standards.
NID, Network Initiated Device test. Operator test category where the network triggers an action on the UE rather than the other way around: paging the device from idle, forcing a location update, pushing a CMAS public warning, or initiating a network-side bearer modification. NID tests verify that the device reacts correctly to messages it did not solicit.
NID scenarios are central to operator OAT plans because they exercise behaviour that lab conformance cannot fully cover: a poorly tuned eDRX timer can make a device miss every paging window, an IMS client bug can drop network-initiated MT VoLTE calls, a CMAS handler missing on emergency channels can fail certification in the United States. Reference signalling is in 3GPP TS 24.301 (EMM) and 3GPP TS 24.501 (5GMM). AT&T NID is the historical reference plan for this category. See PTCRB procedure.
NR, New Radio. 5G physical layer specified by 3GPP from Release 15 onwards, covering frequency range 1 (FR1, sub-7 GHz) and frequency range 2 (FR2, millimetre-wave). NR introduces flexible numerology (15, 30, 60, 120, 240 kHz subcarrier spacings), massive MIMO and beam-based access, and supports bandwidths up to 100 MHz in FR1 and 400 MHz in FR2 per component carrier.
NR is defined across the TS 38 series: 3GPP TS 38.211 for physical channels and signals, TS 38.212 for channel coding, TS 38.213 for control procedures, TS 38.214 for data procedures. UE conformance is tested under 3GPP TS 38.521-1 (RF), TS 38.521-2 (FR2 RF) and TS 38.521-3 (performance). NR can be deployed standalone (SA) or non-standalone (NSA) anchored on LTE. See PTCRB tests.
NSA, Normalised Site Attenuation. Site validation method defined by CISPR 16-1-4 that qualifies an Open Area Test Site (OATS), a Semi-Anechoic Chamber (SAC) or a Fully Anechoic Room (FAR) below 1 GHz. A pair of broadband antennas (biconical 30-300 MHz, log-periodic 300 MHz - 1 GHz) is set up at the standard separation (3 m or 10 m) and the insertion loss is measured for several heights and polarisations.
The measured value is then compared to the theoretical NSA computed for the ideal site. The chamber is qualified if the deviation stays within ±4 dB at every frequency. Beyond ±4 dB, absorbers must be added or repositioned. NSA is the entry ticket for any radiated emissions chamber and must be re-run after major changes (absorbers, turntable, ferrites). See the chamber types guide.
OAT, Operator Acceptance Testing. Operator-specific test plan applied on top of PTCRB or GCF certification before a device is allowed to commercially attach to a given operator's network. Each major operator maintains its own OAT plan with its own document references, its own approved labs and its own pass criteria, distinct from the 3GPP conformance tests covered by PTCRB.
In North America the main OAT plans are AT&T NAF (Network Access Feature), Verizon OPC (Open Development Product Certification) and T-Mobile IoT Lab. They add tests on VoLTE attach behaviour, IMS registration, paging response, eDRX/PSM timers, firmware update over the air and CMAS alerts, on top of 3GPP TS 36.523-1 signalling. A device PTCRB-certified but not OAT-approved cannot be sold under the operator's brand. See AT&T NAF certification guide and Verizon OPC certification guide.
OBW, Occupied Bandwidth. Width of the frequency band that contains 99% of the total transmitted power, measured with a spectrum analyser in the conditions defined by the applicable transmitter standard. OBW is a regulatory metric: it tells the surveillance authority that the signal stays inside the channel it has been assigned.
OBW is required by 3GPP TS 36.521-1 for LTE and 3GPP TS 38.521-1 for 5G NR, and by EN 300 328 for 2.4 GHz wideband systems. The FCC version of the test sits under 47 CFR §15.247 for digitally modulated transmitters. OBW is closely linked to the spectral mask: a transmitter that just passes OBW on one band edge will often fail the mask a few kHz further out. See RED tests.
OJEU, Official Journal of the European Union. Daily publication in 24 official languages where every legally binding act of the Union is promulgated. The OJEU is structured in two main series: L (Legislation) for regulations, directives and decisions; C (Communications and Information) for non-binding acts, opinions and, critically for CE marking, the lists of harmonised standard references.
A harmonised standard only grants presumption of conformity once its reference has been published in the OJEU C series under a specific Commission Implementing Decision tied to a directive (for example Directive 2014/53/EU for radio equipment). Withdrawal from the OJEU revokes that presumption, as happened with EN 301 489-3 V2.1.1 in 2020. The OJEU is freely accessible on EUR-Lex (eur-lex.europa.eu). Manufacturers must check the latest C-series list, not just the EN reference, before citing a standard in their EU Declaration of Conformity. See CE procedure.
OTA, Over-The-Air. Has two distinct meanings in certification. (1) OTA testing: RF performance measurement of an integrated antenna device (phone, IoT sensor) in an anechoic chamber, by 3D rotation, to obtain Total Radiated Power (TRP) and Total Isotropic Sensitivity (TIS). Defined by CTIA Test Plan and 3GPP TS 34.114.
(2) OTA update: software or firmware update transmitted by radio rather than wired. From the certification side, OTA updates raise the question of substantial change: a major firmware that changes the bands, the maximum power or the modulation can invalidate the existing FCC/RED certification and require a Class II Permissive Change (FCC) or a delta DoC (EU). See PTCRB tests.
PAPR, Peak-to-Average Power Ratio. Ratio between the peak instantaneous power of a modulated signal and its average power, expressed in dB. PAPR is an intrinsic property of the waveform: a single-carrier constant-envelope signal has a PAPR close to 0 dB, an OFDM signal with hundreds of subcarriers typically sits between 8 and 12 dB depending on bandwidth and coding.
A high PAPR forces the power amplifier to be backed off below its 1 dB compression point so the peaks remain linear, otherwise the constellation distorts, EVM rises and ACLR collapses. PAPR is therefore a budget item in any LTE, NR or Wi-Fi PA design. 3GPP TS 38.521-1 defines test models that fix the PAPR of the stimulus, so that EVM and ACLR limits are comparable between labs. See PTCRB tests.
PCI PTS
Section titled “PCI PTS”PCI PTS, PCI PIN Transaction Security. PCI Security Standards Council framework that sets the physical and logical security requirements for PIN acceptance devices: payment terminals, encrypting PIN pads and card readers. It protects cardholder data and the PIN against hardware attacks, including tamper detection and key erasure.
PCI PTS certification of a payment terminal comes on top of CE marking, radio certification and EMV
PDCP, Packet Data Convergence Protocol. Sub-layer of the 3GPP radio stack that sits between RLC and the upper layers (RRC for signalling, IP for the user plane). PDCP performs header compression (RoHC), ciphering and integrity protection, in-sequence delivery, duplicate detection, and packet duplication for high-reliability bearers.
PDCP is specified by 3GPP TS 36.323 for LTE and 3GPP TS 38.323 for 5G NR. It is the layer where AS-level security is enforced once the AKA procedure has produced the keys: any UE conformance test plan dedicates a block of cases to PDCP ciphering, integrity, and SN handling. PDCP is also central to dual connectivity (LTE + NR) and to handover, where the PDCP context is preserved across cells. See PTCRB procedure.
Peak detector
Section titled “Peak detector”Peak detector, PK. CISPR weighting detector defined by CISPR 16-1-1 that holds the maximum value of the envelope over the dwell time, with no impulse weighting. It is by construction the fastest detector and always returns a value greater than or equal to the quasi-peak reading.
Peak is used in EMC labs as the pre-scan detector to sweep the full band quickly (typical 1 ms/MHz with a CISPR-band 9 kHz RBW), identify candidate peaks, and only those that come close to the QP or AV limit are then re-measured slowly with the reference detector. Peak is also the measurement detector above 1 GHz in CISPR 32, where it carries a separate limit always above the AV limit. The ANSI counterpart is ANSI C63.4. See the radiated emissions guide.
PEF, Product Environmental Footprint. EU life-cycle assessment methodology consolidated in Recommendation (EU) 2021/2279, designed to provide harmonised, comparable environmental information for products placed on the European market.
PEF covers sixteen impact categories, including climate change, ozone depletion, acidification, eutrophication (freshwater, marine, terrestrial), particulate matter, ionising radiation, photochemical ozone formation, ecotoxicity, human toxicity, land use, water use and resource use (minerals/metals and fossils). Methodological choices follow ISO 14040 and ISO 14044 and rely on the EF reference data sets. Product-specific rules, called PEFCR (Product Environmental Footprint Category Rules), are developed by industry consortia and validated by the Commission to ensure inter-product comparability within a category. PEF feeds the substantiation of green claims and the calculation of footprint indicators required under ESPR. See Ecolabel and PEF guide.
Performance Level
Section titled “Performance Level”Performance Level, PL, machine-safety performance level under ISO 13849. Discrete measure, from a (lowest) to e (highest), of the ability of a safety-related part of a control system to perform a safety function under foreseeable conditions, defined by ISO 13849-1. PL combines architecture, mean time to dangerous failure (MTTFd), diagnostic coverage and common-cause failures.
For a machine safety function, the designer compares the achieved PL against the required PL (PLr) derived from the risk assessment, within CE Machinery marking. PL is the probabilistic counterpart, on the ISO 13849 side, of the SIL and SILCL of IEC 62061. See the CE pillar.
Presumption of conformity
Section titled “Presumption of conformity”Presumption of conformity: Legal effect by which a product designed and tested against a harmonised standard whose reference is published in the OJEU is presumed to meet the corresponding essential requirements of the applicable directive or regulation. The mechanism is set out in Article 4 of Regulation 1025/2012 on European standardisation and reiterated by every NLF directive.
Presumption shifts the burden of proof: the market surveillance authority must demonstrate non-conformity, instead of the manufacturer demonstrating conformity. Applying the harmonised standard remains voluntary, the manufacturer may always demonstrate conformity by other technical means, but loses the procedural advantage. Presumption is granular: a standard published only in part covers only the clauses listed in the Implementing Decision. It can also be revoked, in which case any DoC citing the obsolete reference must be updated within the transition period given in the OJEU notice. See CE technical file.
PSD, Power Spectral Density. Power per unit of bandwidth, expressed in dBm/MHz or dBm/Hz depending on the regulation. PSD is the unit in which several modern radio rules are written, because it normalises the EIRP limit against the channel width the device actually uses.
In 6 GHz Wi-Fi (Wi-Fi 6E and Wi-Fi 7), the FCC 47 CFR §15.407 Low Power Indoor regime is expressed in dBm/MHz so that 20, 40, 80 and 160 MHz channels share a common power budget. UWB devices under FCC Part 15 Subpart F and EN 302 065 are constrained to typically (-41.3 dBm/MHz) averaged across the 3.1 to 10.6 GHz band. Working in PSD also keeps the limit consistent when the regulator approves wider channels later. See FCC standards.
PTCRB, PCS Type Certification Review Board. Certification scheme run by CTIA for cellular devices on US operators' networks (AT&T, Verizon, T-Mobile, US Cellular). PTCRB tests against 3GPP specifications (TS 36.521, TS 38.521, TS 36.523-1) and against operator-specific test plans.
PTCRB is the historical North American "type approval" gate for 2G/3G/4G/5G devices. It does not replace the FCC ID, both are required. A device that integrates a PTCRB-certified module under modular approval can inherit the certification, with restrictions (Critical Components List). PTCRB is closely articulated with GCF, OmniAir (V2X) and CTIA. See PTCRB pillar and PTCRB procedure.
Quasi-peak detector
Section titled “Quasi-peak detector”Quasi-peak detector, QP. CISPR weighting detector defined by CISPR 16-1-1 that emulates the annoyance a human receiver would feel from an impulsive interferer. Built on a fast charge time, a much longer discharge time and a defined mechanical meter time constant, so a rare but tall impulse is heavily attenuated while a continuous carrier is read at its full level.
The quasi-peak is the reference detector for radiated and conducted emissions limits in CISPR 32 / EN 55032 and most product standards. It is also the slowest to measure (around 1 s per point), so labs use peak as a pre-scan and switch to QP only on suspect peaks. A QP reading is always between average and peak; for narrowband CW it converges to peak, for pure impulse noise it sits well below. See CE tests and the radiated emissions guide.
RACH, Random Access Channel. 4G and 5G initial-access procedure by which a UE that is not yet synchronised on the uplink requests resources from the base station. The UE picks a preamble in a configured set, transmits it on the PRACH, and waits for a Random Access Response (RAR) carrying a timing advance and an uplink grant.
RACH is used at power-on, after a long idle period, during handover, and to recover from radio link failure. The procedure is specified by 3GPP TS 36.321 (LTE MAC) and 3GPP TS 38.321 (NR MAC), with both contention-based (4-step in LTE/NR, 2-step in NR Rel-16) and contention-free variants. PTCRB and GCF tests exercise RACH timing, preamble formats and back-off behaviour as part of the signalling test suite. See PTCRB procedure.
RAT fallback
Section titled “RAT fallback”RAT fallback, Radio Access Technology fallback. Mechanism by which a UE drops from a higher-generation radio to a lower-generation one when coverage of the current RAT degrades or when a service is not available on it: 5G NR back to LTE, LTE back to 3G, 3G back to 2G. Fallback can be idle (cell reselection) or connected (handover, redirection, EPS Fallback for voice).
The signalling that governs RAT fallback is split between 3GPP TS 23.501 (5G system architecture) and 3GPP TS 24.301 (EMM for LTE) plus 3GPP TS 24.501 (5GMM). PTCRB and operator OAT plans test fallback under several scenarios: VoLTE call placed on 5G SA falls back to LTE via EPS Fallback, NB-IoT device entering an area without LTE-M finds 2G GSM, automotive eCall forces 2G/3G fallback. Failures usually come from misconfigured PLMN priority lists or broken inter-RAT measurement reports. See PTCRB standards.
RED, Radio Equipment Directive 2014/53/EU. Replaced the R&TTE Directive 1999/5/EC on 13 June 2017. Covers any radio equipment intentionally emitting or receiving radio waves in the EU. RED defines three essential articles: 3.1(a) health/safety, 3.1(b) radio EMC, 3.2 efficient use of spectrum, 3.3 specific requirements (charger, cybersecurity, location for emergency calls...).
Cybersecurity Article 3.3(d)(e)(f) became mandatory on 1 August 2025 for all radio devices connected to the internet, with harmonised standards EN 18031-1, EN 18031-2 and EN 18031-3. RED is self-declaration without Notified Body in the vast majority of cases. See the RED pillar.
Repairability index
Section titled “Repairability index”Repairability index, indice de réparabilité. French scoring framework introduced by the AGEC anti-waste law (loi n° 2020-105) and applicable since 1 January 2021, requiring a 0 to 10 score to be displayed at the point of sale for certain categories of electrical and electronic equipment.
The score is computed by the manufacturer from five weighted criteria: documentation, ease of disassembly, availability and lead time of spare parts, price of spare parts and product-specific sub-criteria. Initial categories covered smartphones, laptops, washing machines, televisions and lawn mowers, later extended to dishwashers, vacuum cleaners and high-pressure cleaners. The French index is being progressively replaced by a durability index and feeds the design of the EU-wide Repair Score under ESPR. Non-display or false declaration is sanctioned by the DGCCRF. See ESPR ecodesign guide.
RoHS, Restriction of Hazardous Substances, Directive 2011/65/EU (RoHS 2) and its amendment 2015/863 (RoHS 3). Restricts the use of ten hazardous substances in electrical and electronic equipment: lead, mercury, cadmium, hexavalent chromium, PBB, PBDE, four phthalates (DEHP, BBP, DBP, DIBP).
Maximum tolerated concentration: 0.1 % by weight in homogeneous material (0.01 % for cadmium). Conformity is demonstrated by IEC 63000 (documentary methodology, supplier declarations) and/or analytical testing under EN 62321. RoHS is part of the directives covered by CE marking, its absence invalidates the CE. See CE scope.
Root of Trust
Section titled “Root of Trust”Root of Trust (RoT), minimal trustworthy substrate. Smallest set of hardware and firmware functions that the rest of the system depends on and that cannot itself be verified by software, because it is implicitly trusted. The Root of Trust holds public keys, the unique device identity and the entropy source used to bootstrap secure boot, attestation, key storage and signed updates.
A Hardware Root of Trust (HRoT) materialises this concept in a tamper-resistant component: a discrete TPM 2.0 (ISO/IEC 11889), an embedded Secure Element such as ATECC608 or SE050, or an on-die crypto block protected by eFuses. The HRoT is required under IEC 62443-4-2 CR 1.5 and is implicit in ETSI EN 303 645 provision 5.4. Without a hardware RoT, signing keys end up in flash, where a read-out attack defeats the whole architecture. See the EN 303 645 guide.
RRM, Radio Resource Management. Family of tests within 3GPP that verifies the device's ability to manage cellular resources: cell selection and reselection, handover between cells, signal measurement, power adjustment, idle/connected mode transitions. Defined by 3GPP TS 36.521-3 (LTE) and 3GPP TS 38.521-4 (NR).
RRM tests are the longest in a PTCRB campaign (often 4 to 6 weeks of laboratory time) because they require simulating dozens of network scenarios with a Network Emulator. Several hundred test cases must pass, a single major RRM failure can block PTCRB approval and operator NID. See PTCRB tests.
RX diversity
Section titled “RX diversity”RX diversity, receive diversity. Reception technique that uses two or more antennas on the UE side to improve sensitivity and resilience to fading. The two RX paths see uncorrelated channels, the baseband combines them (maximum ratio combining or equivalent) and recovers a signal stronger than what each individual antenna would deliver.
RX diversity is mandatory on most 4G and 5G bands per 3GPP TS 36.101 (LTE) and 3GPP TS 38.101-1 (5G NR), and is enforced by operator OAT requirements such as AT&T NAF and Verizon OPC. Conformance is checked through reference sensitivity tests (REFSENS) per band and per UE category, with and without diversity. Performance is then measured over the air during CTIA TIS / TRP campaigns, where a degraded diversity path shows up as a TIS degradation of several dB. See PTCRB tests.
SAR, Specific Absorption Rate. Quantity of radio-frequency energy absorbed per unit mass of biological tissue, expressed in W/kg. Measured in an anthropomorphic phantom (head SAM, body) filled with a liquid simulating dielectric tissue properties. Reference standards: EN 50360 (head), EN 50566 (body), EN 62209-2 (devices ≤ 100 g).
European limits: 2 W/kg averaged over 10 g of tissue for head/torso, 4 W/kg over 10 g for limbs. FCC limits: 1.6 W/kg averaged over 1 g for head/torso. Mandatory test for any transmitter used within 20 cm of the body (phones, tablets, wearables). The 3 to 5 mm distance between phone and body declared by the manufacturer affects the test result. See RED standards and FCC 47 CFR §2.1093.
SBOM, Software Bill of Materials. Machine-readable inventory of every software component, library and dependency contained in a product, with version, supplier and licence. The SBOM is the equivalent for software of an electronic BOM, and is the cornerstone of supply-chain security.
Two formats dominate: CycloneDX (OWASP, JSON/XML) and SPDX (Linux Foundation, ISO/IEC 5962). The SBOM is required by the EU Cyber Resilience Act (Annex I, manufacturer must "draw up and update" it for the support period), by US Executive Order 14028 for federal suppliers, and is recommended by NIS 2 and IEC 62443-4-1. A complete SBOM lets a CSIRT cross-reference a new CVE against the installed fleet within hours rather than weeks. See RED standards and the Cyber Resilience Act guide.
SDoC, Supplier's Declaration of Conformity. FCC procedure introduced in 2017 (FCC 17-93) that replaced the historical "Declaration of Conformity (DoC) + Verification" pair. SDoC applies to unintentional radiators under Part 15 Subpart B (digital devices class A/B), to certain industrial, scientific and medical equipment (ISM, Part 18), and a few special cases: the manufacturer self-declares conformity, without prior submission to the FCC.
Requirements: test against ANSI C63.4, labelling with manufacturer name and address, conformity statement on user manual, test reports kept for 10 years. There is no FCC ID for SDoC products. SDoC does not apply to intentional radiators (Wi-Fi, Bluetooth, cellular), which still require the Certification procedure with a TCB and an FCC ID under Part 15 Subpart C and beyond. See FCC procedure.
SDR, Software-Defined Radio. Radio whose physical layer (modulation, filtering, channelisation) is implemented in software running on a generic baseband processor or FPGA, rather than dedicated hardware. The SDR allows changing standard (LTE → NR, 433 → 868 MHz) by simple firmware update.
The SDR introduces a delicate question for certification: a firmware that changes bands, modulation or maximum power constitutes a Class III Permissive Change under FCC and a substantial RED modification, requiring partial or full recertification. The FCC distinguishes "controlled" SDRs (mechanism to block unauthorised firmware) from "open" SDRs, with stricter rules for the latter under KDB 442812. See FCC standards.
Secure boot
Section titled “Secure boot”Secure boot, verified boot chain. Boot sequence in which each stage cryptographically verifies the signature of the next before transferring execution, anchored at a hardware Root of Trust that holds the public key (or its hash) in immutable fuses or OTP. Any tampered image stops the chain and triggers a recovery or shutdown path.
A typical embedded chain runs ROM code, then signed bootloader, then signed Linux kernel, then signed dm-verity rootfs. Signing uses ECDSA P-256 or RSA-3072, with key revocation lists stored in eFuses. Secure boot is required by IEC 62443-4-2 CR 3.4 (software and information integrity) and is part of Annex I of the Cyber Resilience Act. ETSI EN 303 645 provision 5.7 mandates the same property for consumer IoT. Without secure boot, every other layer can be bypassed by flashing a malicious image. See the IEC 62443 guide.
SILCL, SIL Claim Limit under IEC 62061. Maximum safety integrity level that an electrical control subsystem of a machine can claim given its architecture, hardware fault tolerance and proof-test interval, defined by IEC 62061. A subsystem cannot contribute to a safety function above its SILCL, even if its failure rate would allow it.
SILCL is the IEC 62061 counterpart of the Performance Level of ISO 13849-1: both standards describe the same machine safety function with convertible metrics, within CE Machinery marking. See the CE pillar.
Spectral mask
Section titled “Spectral mask”Spectral mask, Frequency-domain emission envelope a transmitter must fit under. Template, defined per band and per technology by the relevant standard, that sets the maximum allowed PSD as a function of frequency offset from the carrier. The signal measured on the spectrum analyser must remain below the mask everywhere.
Spectral masks are defined for LTE and NR in 3GPP TS 36.521-1 and 3GPP TS 38.521-1, for 2.4 GHz wideband under EN 300 328, for 5 GHz Wi-Fi under EN 301 893 and for FCC Part 15 digitally modulated devices under 47 CFR §15.247. The mask sets the maximum out-of-band and adjacent channel emissions in a single picture, and tightens fastest near the band edges. A mask failure on one band edge usually points at insufficient output filtering or PA spectral regrowth driven by PAPR. See RED tests.
SRS, Sounding Reference Signal. Uplink pilot transmitted by the UE so that the base station can estimate the uplink channel across a wider bandwidth than the data transmission itself uses. The SRS lets the scheduler pick the best resource blocks, adapt the modulation and coding scheme, and, in TDD systems, exploit channel reciprocity to set downlink precoders.
SRS is defined in 3GPP TS 36.211 for LTE and 3GPP TS 38.211 for 5G NR, with several configurable parameters: periodicity, bandwidth, comb, cyclic shift and antenna port mapping. UE conformance tests check SRS power, EVM and timing in the relevant TS 36.521-1 and TS 38.521-1 cases. SRS is heavily used by massive MIMO gNBs to refine downlink beamforming. See PTCRB tests.
SUL, Supplementary Uplink. 5G NR feature added in Release 15 that gives the UE a second, lower-frequency uplink carrier paired with a higher-frequency downlink. The UE transmits on the SUL when the path loss is too high to close the uplink budget on the main TDD carrier, typically by reusing a low LTE band (band n80, n81, n82, etc.) below 2 GHz.
SUL targets the well-known uplink coverage gap of 5G mid-band TDD deployments (n78 at 3.5 GHz), where downlink works well but the UE PA cannot reach the cell. It is specified in 3GPP TS 38.101-1 with dedicated band combinations and Tx power classes. PTCRB tests SUL band combinations when the UE declares support, and operator profiles increasingly request it on 3.5 GHz devices. See PTCRB tests.
SUMS, Software Update Management System. Software update management system that a vehicle manufacturer must establish and have certified under UNECE R156 to homologate a vehicle that receives software updates, in particular over-the-air (OTA) updates. The SUMS tracks software version identification, hardware compatibility and the integrity of the delivery process.
SUMS is the companion of the R155 CSMS: one covers cybersecurity, the other software update management. Both certificates are required for type approval in countries applying these UNECE regulations. See the CE pillar.
sVSWR, site Voltage Standing Wave Ratio. Site validation method defined by CISPR 16-1-4 that qualifies a chamber for radiated emissions above 1 GHz, where the NSA method is no longer practical. A transmit antenna is moved along six positions on the test volume axis and the receive antenna reads the level variations caused by reflections inside the chamber.
The sVSWR ratio between the highest and lowest reading must stay below 6 dB (linear ratio of 2) at every frequency point. The method is repeated for several volume positions and polarisations. sVSWR essentially measures the quality of the absorbers above 1 GHz: pyramidal foams that work down to 30 MHz often degrade above 6 GHz and need a hybrid ferrite/foam combination. sVSWR is the entry ticket for the upper band of CISPR 32 Class A and B. See the chamber types guide.
TAC, Type Allocation Code. First 8 digits of the IMEI, identifying the device model. The TAC is assigned by GSMA via the official "TAC Allocation" portal, against a fee and after submitting the technical file (specifications, test results, PTCRB/GCF status).
A new TAC is mandatory for any cellular device intended for commercial deployment. Without a TAC, operators block the IMEI. TAC allocation usually conditions PTCRB submission, the GSMA TAC application form even cross-references the PTCRB ID. Migrating a product to a new module (chipset change, major firmware) implies a new TAC. See PTCRB procedure.
TARA, Threat Analysis and Risk Assessment. Threat analysis and cyber risk assessment at the core of ISO/SAE 21434 for automotive. TARA identifies the assets to protect, enumerates threat scenarios, rates their impact and feasibility, then sets security goals and measures to bring the risk to an acceptable level.
TARA is the documentary pivot of a vehicle or component cybersecurity case: its results feed the security concept and the CSMS required by UNECE R155. It is the automotive counterpart of the cyber risk analysis in industrial standards. See the CE pillar.
TCB, Telecommunication Certification Body. Independent body accredited by the FCC to issue Equipment Authorization grants for intentional radiators. Since 2014, the FCC has no longer issued certifications directly, the entire process goes through TCBs. There are about thirty TCBs worldwide (Element, Bay Area Compliance, UL Verification Services, Nemko, TÜV Süd...).
The TCB checks the test report, the technical file, the photographs and the labelling, then issues the FCC ID. Some sensitive cases (SDR, very high power, very high frequency) are reserved for the FCC OET and excluded from TCB scope (KDB 388624 lists exclusions). The TCB is the EU-Notified-Body equivalent for FCC RF certification. See FCC procedure.
TPC, Transmit Power Control. Mechanism that allows a transmitter to dynamically adjust its emission power to the minimum needed for the link. TPC is mandatory in 5 GHz under EN 301 893 in the sub-bands where DFS applies, and in LTE/NR under 3GPP TS 36.213 / 38.213.
TPC requires a minimum dynamic range of typically 6 dB (TPC ≥ 6 dB in 5 GHz Wi-Fi) and verification under EN 301 893 that the device responds correctly to network commands. In cellular, the BTS sends TPC commands every TTI (transmission time interval) to manage interference between adjacent cells. TPC is the cellular cousin of APC for Wi-Fi/BLE. See RED standards.
TRP, Total Radiated Power. Total radiated power by the device measured by 3D rotation in anechoic chamber. TRP integrates the radiation pattern across all directions, in contrast to EIRP which only considers the maximum direction. Defined by CTIA Test Plan and 3GPP TS 34.114.
TRP is the reference metric to characterise over-the-air performance of an integrated antenna: a device with a high TRP radiates effectively, regardless of orientation. PTCRB and CTIA define minimum TRP thresholds per band (e.g. ≥ 16 dBm for LTE band 13). A high TRP correlates with cell range and battery life. See PTCRB standards.
TIS, Total Isotropic Sensitivity. Symmetric receive metric of TRP: average sensitivity of the receiver measured by 3D rotation in anechoic chamber. Expressed in dBm, a more negative TIS indicates better sensitivity (e.g. -100 dBm is better than -95 dBm).
PTCRB and CTIA define maximum TIS thresholds (worst tolerated sensitivity) per band. TIS depends on the antenna efficiency and on the noise injected by the device itself (PCB layout, EMC of digital lines on the analogue front-end). A poorly laid out IoT product can have -10 dB TIS compared with the chipset reference, divided cell range correspondingly. See PTCRB standards.
TSCA, Toxic Substances Control Act. US federal law administered by the EPA that governs the manufacture, import and use of chemical substances in the United States. Section 6(h) in particular restricts several persistent substances, including PIP (3:1), an additive present in some plastics, solders and electronic components.
For electronics exported to the United States, TSCA is the functional counterpart of REACH and RoHS on the EU side: it requires supplier declarations and can ban components that are otherwise compliant in Europe. Documentary compliance relies on the same supply-chain data as RoHS. See CE scope.
UE, User Equipment. 3GPP term designating the mobile device or IoT module connected to a cellular network (LTE, 5G NR, NB-IoT, LTE-M). The UE covers everything that sits on the air interface in front of the base station: smartphone, automotive TCU, tracker, smart meter, cellular module embedded in industrial equipment.
The UE is the object under test in PTCRB and GCF certification. Its conformance is verified against 3GPP TS 36.521-1 for LTE radio, 3GPP TS 38.521-1 for 5G NR radio, and the corresponding TS 36.523 / TS 38.523 signalling test series. The UE category (Cat-1, Cat-4, Cat-M1, Cat-NB1, etc.) sets the maximum throughput and the supported features, and conditions a sizeable share of the test plan. See PTCRB tests.
UKCA marking
Section titled “UKCA marking”UKCA marking, UK Conformity Assessed. UK conformity mark introduced post-Brexit (1 January 2021) for products placed on the Great Britain market (England, Wales, Scotland: Northern Ireland keeps CE under the Windsor Framework). UKCA technically mirrors CE in terms of essential requirements and applicable standards.
Important: the UK has reauthorised the CE marking on a permanent basis for most products since August 2023 (Department for Business and Trade, "Recognition of CE marking: Indefinite extension"). UKCA is therefore optional in most cases, except for medical devices and equipment specifically excluded. Designated Bodies replace Notified Bodies for the UK. See CE scope.
UNECE WP.29 / R155 / R156
Section titled “UNECE WP.29 / R155 / R156”UNECE WP.29, World Forum for Harmonization of Vehicle Regulations. Body of the United Nations Economic Commission for Europe that develops automotive technical regulations applied well beyond Europe. Two of its regulations structure the cybersecurity of connected vehicles: UNECE R155 (cybersecurity and CSMS) and UNECE R156 (software updates and SUMS).
Since July 2024, R155 and R156 are mandatory for the type approval of every new vehicle in countries party to the 1958 Agreement, including the EU. The manufacturer must present valid CSMS and SUMS certificates, backed by an ISO/SAE 21434 approach. See the CE pillar.
UWB, Ultra Wide Band. Radio technology that occupies a very large bandwidth (≥ 500 MHz or ≥ 20 % of the centre frequency) with very low spectral power density. Standardised by IEEE 802.15.4z and used for indoor location (Apple AirTag, Samsung SmartTag+), keyless access (BMW Digital Key, Volkswagen) and short-range communication.
UWB is allowed in the 3.1-10.6 GHz band in the US under FCC Part 15 Subpart F and 6-9 GHz in the EU under EN 302 065, with very low EIRP (-41.3 dBm/MHz typical). EMC: EN 301 489-53. UWB does not interfere with co-located narrowband signals because of its low PSD. See RED standards.
VEX, Vulnerability Exploitability eXchange. Companion document to an SBOM that states, for a given CVE affecting a listed component, whether the product is actually exploitable. The four canonical statuses are not_affected, affected, fixed and under_investigation, each with a justification code (e.g. "vulnerable_code_not_in_execute_path").
VEX is specified by NIST/CISA and exists in three serialisations: CycloneDX VEX, CSAF 2.0 (OASIS) and OpenVEX. Without VEX, a single critical CVE in a bundled library generates hundreds of false positives across customer asset-management dashboards. With VEX, the vendor can declare "not_affected, code path disabled at compile time" and silence the alert with audit trail. VEX is referenced by the Cyber Resilience Act guidance and by IEC 62443-2-3 for patch management. See the Cyber Resilience Act guide and IEC 62443 industrial cyber guide.
VoLTE, Voice over LTE. Native voice service on 4G network, IMS-based, replacing 2G/3G circuit-switched voice. VoLTE allows simultaneous voice + data on 4G and improves call quality (AMR-WB / EVS codec) and call setup time (< 2 s vs. 5-7 s in 3G).
VoLTE is required by all major US operators (AT&T, Verizon, T-Mobile) for any cellular device since 2020, the 3G/2G shutdown leaves no fallback. Tests: 3GPP TS 34.229 (IMS), operator OAT/NID. A device that does not pass VoLTE will not obtain operator NID even if PTCRB passes. See PTCRB tests.
VoNR, Voice over New Radio. Native voice service on 5G New Radio standalone (SA), introduced from 3GPP Release 16. VoNR replaces the EPS Fallback transitional solution (5G NSA → 4G LTE for voice) on operator 5G SA networks.
VoNR deployment is still partial in 2026, most 5G operators still use EPS Fallback. PTCRB tests VoNR conformance against 3GPP TS 38.521-1 and TS 34.229. Roadmap towards "full 5G voice" depends on the 5G SA network coverage of each operator and the corresponding firmware/baseband support. See PTCRB pillar.
WEEE, Waste Electrical and Electronic Equipment, Directive 2012/19/EU. Requires manufacturers and importers of EEE to organise free collection, treatment and recycling of end-of-life products. Implemented in France via the éco-organisme model (Ecologic, Ecosystem).
The WEEE compliance scheme requires registration in each Member State, payment of a contribution per unit placed on the market, and visible affixing of the crossed-out wheeled bin pictogram on the product or its packaging (EN 50419). WEEE accompanies CE marking but does not fall under it strictly speaking, it is a separate obligation under the CE umbrella. See CE scope.
Wi-Fi: Family of wireless local area network technologies based on the IEEE 802.11 standard. Generations: 802.11b/g (2.4 GHz), 802.11n (Wi-Fi 4), 802.11ac (Wi-Fi 5), 802.11ax (Wi-Fi 6 / 6E with 6 GHz), 802.11be (Wi-Fi 7), 802.11bn (Wi-Fi 8, in progress).
From the certification side, Wi-Fi falls under RED in the EU (EN 300 328 2.4 GHz, EN 301 893 5 GHz, EN 303 687 6 GHz) and FCC Part 15 Subpart C/E in the US. The Wi-Fi Alliance also runs a Wi-Fi CERTIFIED certification for interoperability, distinct from regulatory conformity. See RED standards and FCC standards.
ZTA, Zero Trust Architecture. Security model in which no user, device or network segment is trusted by default, even inside the corporate perimeter. Every access request is authenticated, authorised and continuously evaluated against device posture, identity and context. The maxim "never trust, always verify" replaces the legacy castle-and-moat approach.
The reference document is NIST SP 800-207, which defines seven tenets including per-session access decisions and dynamic policy. ZTA relies on strong identity (FIDO2, mutual TLS), micro-segmentation, attestation of device state, and continuous telemetry. The model is recommended by US Executive Order 14028 for federal networks and by ENISA for critical infrastructure under NIS 2. In an industrial context, IEC 62443-3-3 system requirements (SR 1.x, SR 2.x) align naturally with ZTA tenets. See IEC 62443 industrial cyber guide.
Numbers and abbreviations
Section titled “Numbers and abbreviations”3GPP, 3rd Generation Partnership Project. Worldwide collaboration of standards bodies (ETSI for Europe, ATIS for the US, TTC and ARIB for Japan, TTA for Korea, CCSA for China, TSDSI for India) that drafts cellular standards from 3G UMTS to 5G NR and the future 6G. 3GPP publishes Releases (Rel-15 = first 5G NR, Rel-17 = NR-Light/RedCap, Rel-18 = 5G-Advanced).
3GPP specifications are organised into Technical Specifications (TS) by series: 22 (services), 23 (architecture), 24 (signalling), 36 (LTE), 38 (NR). PTCRB and GCF test against 3GPP TS, knowing the version of the Release supported by the module is structuring for any IoT product roadmap. See PTCRB standards.
47 CFR
Section titled “47 CFR”47 CFR, Code of Federal Regulations, Title 47. Part of US federal regulation devoted to telecommunications, administered by the FCC. The 47 CFR contains around 80 parts, of which the most cited in certification are Part 2 (general), Part 15 (radio frequency devices, including Wi-Fi/BLE/SRD), Part 22 (cellular), Part 24 (PCS), Part 27 (broadband flexible-use), Part 90 (private mobile radio), Part 95 (personal radio).
A specific reference is cited in the form 47 CFR §15.247 (FHSS/DSSS systems 2.4/5.8 GHz) or 47 CFR §15.407 (U-NII 5 GHz). The 47 CFR is updated continuously by the FCC via Public Notices and KDB publications. See FCC standards.