Subarray-based frequency diverse array radar for target range-angle estimation

• Published in: IEEE transactions on aerospace and electronic systems Vol. 50; no. 4; pp. 3057 - 3067
• Main Author: Wang, Wen-Qin
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-10-2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Array signal processing; Estimation; Interference; Phased arrays; Radar; Signal to noise ratio
• ISSN: 0018-9251; 1557-9603
• DOI: 10.1109/TAES.2014.120804

Phased-array is widely used in communication, radar, and navigation systems, but the beam steering is fixed in an angle for all range cells. Frequency diverse array (FDA) provides a range-dependent beamforming, but it cannot estimate directly both the range and angle of a target. This paper proposes a subarray-based FDA radar, with an aim to localize the target in the range-angle domain.We divide the whole FDA array into two subarrays, which employ two different frequency increments. In doing so, the target's range and angle are estimated directly from the transmit-receive beamforming output peak. The estimation performance is examined by analyzing the minimum mean variance square error (MMSE) and the Cramer-Rao lower bound (CRLB) versus signal-to-noise ratio (SNR). The corresponding transmit-receive beampattern and signal-to-interference plus noise ratio (SINR) are also formalized. Moreover, the CRLB can be used to optimally design the frequency increments. The effectiveness is verified by simulation results.