Radar Classes: SRR, MRR, LRR
SRR, MRR, and LRR refer to standardized automotive radar classes that differ in detection range and application. They are subject to EMC and radio compliance requirements under regulations such as ECE-R-10 and the Radio Equipment Directive.
Scope and Application
Automotive radar systems are deployed in passenger cars and commercial vehicles to enhance driving safety and situational awareness. Typical applications include:
SRR (Short-Range Radar): Monitoring of blind spots, parking assistance, stop-and-go functionality; detection range up to approx. 30 meters
MRR (Mid-Range Radar): Lane change assist, cross-traffic alert; range up to approx. 150 meters
LRR (Long-Range Radar): Adaptive cruise control, highway pilot features; range up to approx. 250 meters
Radar sensors are often integrated into bumpers or behind emblems and require precise calibration and testing to meet regulatory and performance standards.
Key Technical Requirements
Radar sensors must comply with both regulatory and functional requirements:
Frequency allocations: Typically operate in the 24 GHz or 76–81 GHz bands (subject to regional regulation)
Transmitter power: Must remain within defined limits (e.g., per ETSI EN 301 091, FCC Part 95)
EMC and RF testing: Required under frameworks such as ECE-R-10, RED (EU), or FCC/ISED (US/Canada)
Performance parameters: Include range accuracy, angular resolution, multi-target detection, and noise immunity
Pre-compliance testing, validation in real-world scenarios, and calibration of emission power are essential to achieve type approval.
Certification and Compliance
Depending on the target market, the following frameworks may apply:
Europe: ECE type approval under ECE-R-10, combined with RED compliance
North America: FCC/ISED radio approval and conformity with local EMC standards
Other markets: Country-specific homologation (e.g., MIC Japan, KC South Korea)
Radar systems must be tested in accredited laboratories to ensure conformity and reliability under electromagnetic and environmental stress conditions.
Lifecycle Relevance
Radar classes play a key role throughout the automotive development lifecycle:
Early-stage performance verification (e.g., noise immunity, range validation)
EMC and RF type approval testing before market entry
Reassessment after hardware updates or functional extensions