Direct Position Determination With a Moving Extended Nested Array by Spatial Sparsity.

Direct position determination (DPD) has received much attention in emitter localization, owing to its better accuracy than conventional two-step positioning. Most of the existing DPD algorithms are developed for circular signals by using uniform linear arrays (ULAs). However, these algorithms may ignore other characters of the signals, e.g., non-circularity. The use of ULAs limits the accuracy of source localization and the number of sources that can be estimated. In this paper, a weighted ℓ0-norm sparse reconstruction algorithm for non-circular signals is developed for DPD with a designed sparse array in motion. Firstly, a sparse array configuration named extended nested array is devised for non-circular signals, which consists of three subarrays. Theoretical analysis proves that the designed array can obtain higher degrees of freedom (DOFs) effectively, and reduce the mutual coupling effects between antennas. Then, a weighted ℓ0-norm sparse reconstruction algorithm is developed to improve the accuracy of DPD. Finally, simulation results are provided to demonstrate the superiority of the proposed algorithm with the designed sparse array. Our scheme can provide better localization performance than the state-of-the-art methods.