Optimization of Target Detection Performance in Rotating Multichannel Radar Systems

Abstract

In the application of automotive radar, vehicle turning is a critical scenario. The introduction of rotational angular velocity causes Doppler shifts in forward-facing speed radars, leading to defocusing of multichannel echo data. This paper attempts to propose a method for compensating and correcting the rotational angular velocity to focus the energy across channels by compensating for the speed in each channel. Considering the rotational angles of the vehicle-mounted platform, the real incident angle of an unknown target must be accounted for since the main beam covers a relatively large range. Therefore, we include the target’s angle of arrival, conducting a search within the main beam range during detection. When the true angle of arrival of the target is identified, detection performance reaches its optimal level. After, employing the rotational speed search method proposed in this paper, under a four-channel rotating radar platform, the signal-to-noise ratio (SNR) for target detection is enhanced by approximately 15 dB, which aligns with the theoretical gain from coherent accumulation of SNR derived in the subsequent sections of the paper. Furthermore, obtaining the exact value of the platform’s rotational speed may not always be easy. Hence, we incorporate the rotational speed into the search range. After, performing a two-dimensional search, the peak of the detection performance graph corresponds to the true rotational speed of the vehicle-mounted platform and the angle within the main beam range where the target is located. Conversely, knowing the prior information of any dimension in the two-dimensional search can expedite and improve the detection performance of the other dimension’s parameters.