A Medium Range Low-Cost Monopulse Radar System for Azimuth and Range Detection at 24GHz

The paper presents details and results on a high-performance, medium-range monopulse radar system designed for various automotive applications, with a particular emphasis on the implementation and accuracy of the azimuth detection functionality. Whilst, by comparison, front-end radar systems for range and/or speed detection are relatively straightforward to implement, the addition of the azimuth functionality, indispensable in most automotive applications, is in fact an extremely difficult task. This task is even more challenging when such a system has to be low-cost. The system that we have developed is based on a compact low-cost Tx/Rx front-end design at 24GHz. A brief overview of the system and sub-system design details and their performances are outlined. Very reliable and accurate azimuth detection functionality has been implemented by employing a variant of the phase/amplitude comparison monopulse solution, using a high-performance patch-array antenna. Some of the main performance parameters achieved with the system described here include: range/speed detection of more than 50 meters, an azimuth range of plusmn 40deg with azimuth accuracy better than 1deg in the very important low-azimuth angle range. The paper includes some of the final system test results, showing the measured azimuth performance, for the antenna itself as well as for the entire front end system.