Range-Doppler domain spatial alignment for networked radars

Xiaoyu Cong,Weixing Sheng,Hui Sun,Shanhong Guo,Yubing Han

doi:10.1186/s13634-022-00849-4

Abstract

An important prerequisite for the radar network detection is that the measurements from local radars are transformed to a common reference frame without systematic or registration errors. For the signal level alignment, only partial signals are available for global decision-making due to power and bandwidth limitations. In this paper, a low-communication-rate spatial alignment in range-Doppler domain is proposed for networked radars without the prior spatial information (positions and attitudes) of radars, which is different from the existing methods in the trajectory domain or echo domain for alignment. To reduce the radar-to-fusion-center communication-rate, the method of initial constant false alarm rate detection is used to censor the signals in range-Doppler domain from local radars. Based on the spatial alignment model for the networked radars in geometry, a maximization problem is formulated. The objective function is the cross-correlation between the range-Doppler domain signals from different local radars. The optimization problem is solved by a genetic algorithm. Simulation results show that the rotation matrix and translation vector are estimated, and the detection probability of the proposed algorithm is improved after alignment and fusion compared with state-of-art methods.

Highlights

Networked radars can share different views of data from multiple stand-alone radars for fusion so as to improve the target tracking accuracy
The spatial alignment algorithm is simulated in single target and Carrier frequency fc/GHz Pulse width Tp/us Pulse repetition period Tr/us Pulse repetition interval (PRI) number in one coherent processing interval (CPI) N Sampling rate fs/MHz Bandwidth B/MHz Noise factor Fn/dB
A low-communication-rate spatial alignment in range-Doppler domain was proposed for networked radars without the prior information of radars

Summary

Introduction

Networked radars can share different views of data from multiple stand-alone radars for fusion so as to improve the target tracking accuracy. A low-communication-rate algorithm is proposed to estimate the spatial alignment parameters for networked radars in range-Doppler domain. A spatial alignment algorithm in range-Doppler domain is proposed for networked radars without the prior information including positions and attitudes of local radars, which is different from the existing methods in trajectory or echo domain for alignment and improves the alignment accuracy. Compared with the echo signal, the signals in range-Doppler domain are accumulates in the frequency domain, which is convenient to extract the target information in low SNRs. Since the complex signals received by different radars are non-coherent, the absolute values of signals after MTD are measured for alignment. The signals SkA,m and SkB,m in range-Doppler domain should be aligned before fusion

Spatial alignment model

Results and discussion

Single target scenario

Conclusions