Thinned Virtual Array for Cramer Rao Bound Optimization in MIMO Radar

Abstract

By transmitting multiple independent waveforms at the transmit side and processing echoes of spatial targets at the receive side, Multiple Input Multiple Output (MIMO) radar enjoys virtual array aperture expansion and more degree of freedom (DOF), both of which favors the application of direction finding or estimation of direction of arrival (DOA). The expanded virtual aperture provides higher angular resolution which also promotes the precision of DOA estimation, and the extra DOF brought by waveform diversity can be leveraged to focus energy in certain spatial region for better direction-finding capacity. However, beamspace methods which match certain beampatterns suffer from deteriorated performance and complexity in implementation, and the advantage of virtual array aperture is limited by its virtual element redundancy. As an important performance indicator of DOA estimation, Cramer–Rao Bound (CRB) is closely connected to the array configuration of the system. To reduce the complexity of the system and improve CRB performance at the same time, in this paper, the virtual array of MIMO radar is designed directly by selecting outputs from matched filters at the receive side. For the sake of fair comparison, both scenarios with and without priori directions are considered to obtain optimized virtual array configuration, respectively. The original combinatorial problems are approximated by sequential convex approximations methods which produce solutions with efficiency. Numerical results demonstrate that the proposed method can provide thinned virtual arrays with excellent CRB performance.

Multisource DOA Estimation in Impulsive Noise Environments Using Convolutional Neural Networks

“…In recent years, direction-of-arrival (DOA) estimation has been extensively applied in many fields, such as radar, sonar, electronic monitoring, and mobile communication [1][2][3]. It is the critical technology of array signal processing, and the purpose is to estimate the transmitter positions of the signals received by arrays.…”

Recent Advances in Design and Signal Processing for Antenna Arrays 2020

“…Roughly speaking, they fall into the following four main topics. Te frst topic is antenna design for array applications, including one paper titled "Development of a Pin Diode-Based Beam-Switching Single-Layer Refectarray Antenna" [12]; the second topic is antenna array pattern synthesis, including one paper titled "Two-Dimensional Beampattern Synthesis for Polarized Smart Antenna Array and Its Sparse Array Optimization" [13]; the third topic is direction/angle of arrival estimation, including two papers, titled "Tinned Virtual Array for Cramer Rao Bound Optimization in MIMO Radar" and "Nonuniformly Spaced Array with the Direct Data Domain Method for 2D Angle-of-Arrival Measurement in Electronic Support Measures Application from 6 to 18 GHz" [14,15], respectively; the last topic is target detection and localization (range/velocity/angle estimation) based on antenna arrays, including two papers, titled "Spread Sea Clutter Suppression in HF Hybrid Sky-Surface Wave Radars Based on General Parameterized Time-Frequency Analysis" and "Maximum Likelihood Angle-Range Estimation for Monostatic FDA-MIMO Radar with Extended Range Ambiguity Using Subarrays" [16,17], respectively.…”