Millimeter Wave Specific Challenges mmWave Radar and Sensing Informational

What are the FCC and ETSI regulatory requirements for millimeter wave radar sensors?

Q: Do I need FCC certification for a prototype?

For internal R&D and development: the FCC allows operation of unregistered devices under the experimental radio service (FCC Part 5) or under the general exemption for R&D devices that are not marketed or sold. No FCC ID is required for prototypes used in the lab or at test facilities. However: if the prototype operates outdoors or could affect other spectrum users: an experimental license should be obtained (FCC Form 442, $80 application fee, 30-60 day processing). For trade shows and demonstrations: the FCC allows limited demonstration under Part 5 with a permit (STA: Special Temporary Authority). For any device that is sold, marketed, or imported for sale: full FCC certification (FCC ID) is required before the device can be legally operated.

Q: How do regulations differ for occupant detection vs automotive radar?

In-cabin radar (occupant detection, gesture control): typically operates at 60 GHz (57-71 GHz) under FCC Part 15.255 / ETSI EN 302 567. Lower EIRP (+20 to +30 dBm) since the range is short (< 2 m). The key regulatory concern is RF exposure: the sensor is close to people (the occupants). The power density at the occupant nearest point must be < 1 W/m² (public exposure limit). This limits the maximum EIRP based on the sensor-to-occupant distance. Automotive exterior radar: operates at 77 GHz (76-81 GHz) under FCC Part 95 / ETSI EN 302 264. Higher EIRP (+40 to +55 dBm) for longer range. RF exposure: the radar is mounted behind the bumper/fascia. The nearest person is at least 20-30 cm away. At +50 dBm EIRP (100 W): power density at 30 cm = 100/(4π×0.09) = 88 W/m² (exceeds the occupational limit). However: the radar beam is typically narrow (5-10°), and the power density is lower at angles away from the beam peak. Compliance is demonstrated by calculating the power density at all accessible locations.

Q: What about radar operation in tunnels or confined spaces?

In tunnels and confined spaces: the radar signal may reflect multiple times from walls and ceiling, creating multipath that appears as false targets. This is a sensor design challenge, not a regulatory issue. Regulatory: the same regulations apply in tunnels as in open air. The radar operates within its certified power limits. No additional certification is needed. Special consideration: some tunnels contain radiation-sensitive equipment (e.g., leaky feeder cables for radio communication, toll collection transponders). If there is a concern about interference: contact the tunnel operator and the relevant radio frequency coordination body.

mmWave radar sensors must comply with regulatory requirements from the FCC (USA), ETSI (Europe), and other regional authorities. Key regulations: (1) 76-81 GHz (automotive radar band): FCC Part 95 (previously Part 15.253): EIRP max: +55 dBm peak, +50 dBm average. Bandwidth: full 76-81 GHz (5 GHz). No license required (type-approval certification). Applications: unlimited (automotive, industrial, commercial). ETSI EN 302 264 (EU): EIRP max: +55 dBm peak, +50 dBm mean. Bandwidth: 76-77 GHz (exclusive automotive radar) and 77-81 GHz (short-range radar). Applications: automotive and infrastructure. The 76-81 GHz band is globally harmonized: similar regulations in Japan, Korea, China, and other markets. (2) 57-71 GHz (V-band, 60 GHz ISM): FCC Part 15.255: EIRP max: +40 dBm (10 W). Bandwidth: up to 14 GHz (57-71 GHz). No license required. Applications: radar sensing (short range), WiGig, and point-to-point communication. ETSI EN 302 567: EIRP max: +40 dBm. Bandwidth: 57-66 GHz (EU allocation). Applications: similar to FCC. This band is used for: indoor presence detection, gesture recognition, health monitoring, and short-range communication (WiGig/802.11ad/ay). (3) 24 GHz (ISM band): FCC Part 15.245/15.249: narrowband (24.0-24.25 GHz): EIRP max: +20 dBm. Used for: simple motion detection, speed measurement. UWB (22-29 GHz, FCC Part 15.515): power spectral density max: -41.3 dBm/MHz, EIRP max: +20 dBm. This band is being sunset in the EU (ETSI EN 302 288: expired for new automotive radar in 2022). (4) Certification process: FCC: submit the device for testing by an accredited test lab (TUV, UL, Intertek). The lab measures the radiated emissions, verifies compliance with the power limits, and issues a test report. The manufacturer files the test report with the FCC and obtains an FCC ID. Duration: 4-8 weeks. Cost: $5,000-$15,000 per device. EU: the manufacturer conducts or commissions testing per the harmonized standard (EN 302 264 or EN 302 567). A notified body reviews the documentation. The manufacturer self-declares compliance and applies the CE mark.

Category: Millimeter Wave Specific Challenges

Updated: April 2026

Product Tie-In: Radar ICs, Antennas, Signal Processors

mmWave Radar Regulations

Regulatory compliance is a non-negotiable requirement for any commercial radar product. The regulations balance the need for radar functionality with the protection of other spectrum users.

Power and Emission Limits

(1) 76-81 GHz specifics: the FCC Part 95 limits apply to vehicular radar. Fixed infrastructure radar: FCC Part 15.256 may apply (different limits for outdoor fixed radar). The EIRP limit of +55 dBm (316 W) is very generous; most automotive radars operate at +40 to +50 dBm EIRP. The regulation also specifies: out-of-band emissions (OOB): must be < -30 dBm/MHz at > 200 MHz from the band edge. Spurious emissions: must be < -41.3 dBm/MHz outside the band. Antenna requirements: the antenna gain and beam patterns are not explicitly limited (only the EIRP is regulated). (2) 57-71 GHz specifics: the regulations distinguish between indoor and outdoor use in some jurisdictions. In the EU: 57-66 GHz is for both indoor and outdoor (with EIRP ≤ +40 dBm). 66-71 GHz: additional 5 GHz is being proposed for outdoor use. In the US: 57-71 GHz is available for both indoor and outdoor (FCC Part 15.255). (3) Safety exposure: in addition to spectrum regulations, the device must comply with RF exposure limits: FCC OET Bulletin 65: limits the power density at the device surface and at various distances. For handheld devices (< 20 cm from the body): SAR limits apply (for frequencies below 6 GHz). For mmWave: the applicable limit is power density (W/m²) at 5 cm from the radiating surface. Limit: 10 W/m² for occupational, 1 W/m² for public (averaged over 4 cm²). A radar sensor with +20 dBm EIRP (0.1 W): at 5 cm distance: power density = 0.1 / (4π×0.05²) = 3.2 W/m² (exceeds the public limit). The radar must either: reduce EIRP, or ensure that the public cannot be within 5 cm of the sensor during operation (by enclosure design or placement).

Country-Specific Considerations

(1) Japan: MIC (Ministry of Internal Affairs and Communications): 76-81 GHz radar is approved under the Radio Law. Similar limits to FCC/ETSI. Additional: the radar must not interfere with radio astronomy at 72-86 GHz. The radar emissions within 72-76 GHz must be below -65 dBm/MHz. (2) China: MIIT (Ministry of Industry and Information Technology): 76-81 GHz approved for automotive radar (GB/T standard). The certification process includes testing by a MIIT-accredited lab (CTTL, etc.). Lead time: 8-16 weeks (longer than FCC). (3) Korea: KCC (Korea Communications Commission): 76-81 GHz approved. Similar limits to ETSI. KC mark certification required. (4) India: WPC (Wireless Planning Commission): radar regulations are evolving. As of 2025: 76-81 GHz is approved for automotive use. Testing by WPC-accredited labs. Lead time: 12-24 weeks.

Regulatory Power Limits

76-81 GHz: EIRP ≤ +55 dBm (FCC/ETSI)
57-71 GHz: EIRP ≤ +40 dBm
24 GHz NB: EIRP ≤ +20 dBm
OOB emission: < -30 dBm/MHz
MPE: 10 W/m² occupational, 1 W/m² public

Common Questions

Frequently Asked Questions

Do I need FCC certification for a prototype?

For internal R&D and development: the FCC allows operation of unregistered devices under the experimental radio service (FCC Part 5) or under the general exemption for R&D devices that are not marketed or sold. No FCC ID is required for prototypes used in the lab or at test facilities. However: if the prototype operates outdoors or could affect other spectrum users: an experimental license should be obtained (FCC Form 442, $80 application fee, 30-60 day processing). For trade shows and demonstrations: the FCC allows limited demonstration under Part 5 with a permit (STA: Special Temporary Authority). For any device that is sold, marketed, or imported for sale: full FCC certification (FCC ID) is required before the device can be legally operated.

How do regulations differ for occupant detection vs automotive radar?

In-cabin radar (occupant detection, gesture control): typically operates at 60 GHz (57-71 GHz) under FCC Part 15.255 / ETSI EN 302 567. Lower EIRP (+20 to +30 dBm) since the range is short (< 2 m). The key regulatory concern is RF exposure: the sensor is close to people (the occupants). The power density at the occupant nearest point must be < 1 W/m² (public exposure limit). This limits the maximum EIRP based on the sensor-to-occupant distance. Automotive exterior radar: operates at 77 GHz (76-81 GHz) under FCC Part 95 / ETSI EN 302 264. Higher EIRP (+40 to +55 dBm) for longer range. RF exposure: the radar is mounted behind the bumper/fascia. The nearest person is at least 20-30 cm away. At +50 dBm EIRP (100 W): power density at 30 cm = 100/(4π×0.09) = 88 W/m² (exceeds the occupational limit). However: the radar beam is typically narrow (5-10°), and the power density is lower at angles away from the beam peak. Compliance is demonstrated by calculating the power density at all accessible locations.

What about radar operation in tunnels or confined spaces?

In tunnels and confined spaces: the radar signal may reflect multiple times from walls and ceiling, creating multipath that appears as false targets. This is a sensor design challenge, not a regulatory issue. Regulatory: the same regulations apply in tunnels as in open air. The radar operates within its certified power limits. No additional certification is needed. Special consideration: some tunnels contain radiation-sensitive equipment (e.g., leaky feeder cables for radio communication, toll collection transponders). If there is a concern about interference: contact the tunnel operator and the relevant radio frequency coordination body.

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