Direct Self-Position Determination Exploiting Multiple Noncircular Emitters: A Reduced Dimensional Weighted Propagator Method

The global satellite navigation system is a common tool for self-positioning, but its performance may become weak or interrupted due to obstacles in harsh environments. The application of sensor arrays provides a more flexible and independent satellite self-positioning scheme. We propose a direct self-position determination method based on the sensor array, which exploits multiple noncircular (NC) emitters with known locations and combines reduced dimension and weighted propagator method (WPM). Specifically, the proposed algorithm achieves direct self-position determination by means of the received NC signals. The sensor array aperture is extended by utilizing the elliptic covariance matrix of NC signals, and a reduced dimension approach is applied to eliminate the NC phase search dimension and, thus, reduce the complexity. Due to the different signal attenuation from emitters, a weight based on the estimated signal-to-noise ratio (SNR) is deployed to further improve the performance of the algorithm. In addition, the Cramér-Rao bound (CRB) of the self-positioning problem is derived. Numerical simulations also verify that the proposed method gains higher accuracy and lower complexity compared with the conventional methods.