How do I determine the applicable regulations for a short range radar device in the US and Europe?
Short-Range Radar Regulatory Requirements
Short-range radar regulation is evolving rapidly as automotive, industrial, and consumer radar applications proliferate. Understanding the regulatory landscape across both US and EU markets is essential for product planning and certification.
77 GHz Automotive Radar: The Global Standard
The 76-81 GHz band has converged as the global automotive radar band, with harmonized allocations worldwide. Three sub-bands serve different radar functions: (1) 76-77 GHz: Long-Range Radar (LRR, forward-looking, 200+ meter range for adaptive cruise control and collision avoidance). Maximum EIRP: 55 dBm peak, average power density 23 dBm/MHz per ETSI EN 302 264. (2) 77-81 GHz: Short-Range Radar (SRR, 360° surround sensing, parking assist, blind spot detection, 0.3-30 meter range). Maximum EIRP: 55 dBm peak, 3 dBm/MHz mean density. (3) Combined 76-81 GHz: new generation radar transceivers (TI AWR2944, NXP S32R45, Infineon AURIX TC3xx + MMIC) cover the full 5 GHz bandwidth with chirp bandwidths up to 4 GHz, achieving 3.75 cm range resolution. FCC Part 15.253 allows vehicular radar in 76-77 GHz at 50 dBm EIRP average, and 77-81 GHz (Part 15.252) at -41.3 dBm/MHz. The emission rules differ slightly between FCC and ETSI but practical radar designs meet both.
UWB and Industrial Radar
Ultra-wideband radar (FCC Part 15 Subpart F) operates at very low power density (-41.3 dBm/MHz average EIRP) across extremely wide bandwidths (500 MHz to 7.5 GHz), enabling centimeter-resolution ranging and through-wall detection. Applications: ground-penetrating radar (GPR) for utility detection, through-wall imaging for search and rescue, industrial level measurement, and precision indoor positioning. The FCC defines specific device categories: imaging systems (Part 15.509), vehicular radar (15.515), ground-penetrating radar (15.521), and communication systems (15.517), each with different emission masks and operating restrictions. Medical radar (contactless vital sign monitoring) at 24 GHz and 60 GHz is an emerging application that requires careful compliance with both the radar emission limits and possible FDA medical device regulations depending on the intended use claim.
Certification Process Comparison
US: SRR devices undergo FCC Equipment Authorization (Certification) through a TCB. Testing per the applicable Part 15 subpart includes: transmit power and EIRP measurement, out-of-band emissions, antenna characteristics, and operational verification. Timeline: 6-12 weeks. Cost: $8,000-25,000. EU: radar devices require CE marking under the RED. Testing per the applicable ETSI EN standard. If the available harmonized standard covers the device, self-assessment (Module A) is possible. Otherwise, a Notified Body must assess conformity. Additional complexity: in the EU, the 79 GHz band (77-81 GHz) required a specific European Commission implementing decision (2004/545/EC, amended 2011/485/EU) to authorize vehicular SRR. Timeline: 8-16 weeks. Cost: $10,000-30,000. For automotive Tier 1 suppliers, the product must also pass AEC-Q100 qualification for the radar IC and ISO 26262 functional safety assessment for the radar system, adding 12-18 months to the total qualification timeline.
Frequently Asked Questions
Why did Europe phase out 24 GHz automotive radar?
The 24 GHz wideband SRR allocation at 21.65-26.65 GHz was a temporary authorization intended to bridge the gap until 77 GHz technology matured. The wide bandwidth overlapped the radio astronomy protected band at 23.6-24.0 GHz, and as automotive radar deployment grew to millions of vehicles, the potential for aggregate interference to radio telescopes became significant. CEPT Decision ECC/DEC(04)10 set a January 1, 2022 sunset date for wideband 24 GHz automotive radar in Europe. The narrowband 24 GHz ISM allocation (24.0-24.25 GHz, 250 MHz bandwidth) remains available for industrial and non-automotive applications. All new automotive radar designs now use the 76-81 GHz band exclusively.
Do I need different radar hardware for US vs EU certification?
Generally no, if designed to the more restrictive standard. Modern 77 GHz radar transceivers support the full 76-81 GHz band on a single chip, and firmware configures the chirp parameters (bandwidth, power, repetition rate) to meet specific regional limits. Design the RF front-end to meet the stricter set of requirements (usually ETSI for emission density, FCC for absolute power), and adjust modulation parameters in firmware for each market. The antenna design may differ for markets with different EIRP limits, but increasingly, common antenna modules are used with power back-off for more restrictive markets.
Can I use 77 GHz radar for non-automotive applications?
Yes, the 76-81 GHz band is allocated for radiolocation generally, not exclusively for automotive. Industrial radar systems (level measurement, object detection, drone altitude sensing), security screening, and infrastructure monitoring can operate at 76-81 GHz under the same FCC/ETSI rules. However, the specific emission limits may differ: FCC Part 15.253 has specific provisions for vehicular radar that grant higher power than general Part 15 devices. Non-vehicular applications may need to comply with the lower general Part 15.255 limits in some sub-bands. Check the exact regulatory text for your specific application and deployment scenario.