A 24GHz Low-Cost, Long-Range, Narrow-Band, Monopulse Radar Front End System for Automotive ACC Applications

This paper presents details and results of the development of a low-cost, narrow-band, long range radar (LRR) front end system at 24 GHz, intended for autonomous cruise control (ACC) and other medium and long-range automotive applications. The system uses a high directivity patch array Tx/Rx antenna and a low-cost, high sensitivity RF front end. The narrow band, pulse radar concept is well suited for the applications envisaged, avoiding at the same time some well known regulatory issues related with existing UWB short range systems. The accurate azimuth detection functionality has been implemented by employing a phase/amplitude comparison monopulse solution using a dual receive patch-array antenna. Key performances currently achieved with the new system include: range detection of up to 120 meters for regular car size targets, azimuth detection range of plusmn 8deg, with azimuth accuracy better than 0.3deg. The successful realization of such low-cost, long range radar system at 24 GHz could potentially lead to two important developments in the near future: the implementation of the new radar technologies into the lower class, high volume car market and challenging the dominance of the much more expensive ACC systems currently developed at 77 GHz.