Conical Conformal Array DOA Estimation For Coherent Signal

Due to a series of advantages in physics performance that brings by the special structure characteristics, conformal array is widely applied in ship-board, air-borne, missile-borne, space-borne radar and a plurality of military, civilian areas such as mobile communications. In the perspective of super-resolution DOA estimation, the existing spatial spectrum estimation theory can be applied in the traditional arrays such as ULA effectively, but it is difficult to meet the requirements of full-range testing, so smart conformal array has become a good choice. Aimed at the coherent source scenarios which exist in actual electromagnetic environment frequently and the vacancy of spatial spectrum estimation by conformal array, the estimation of coherent sources based on conical conformal array is studied this paper. The main contents are as follows:First, the structure of the conical conformal array is given, then deriving its general steering vector model based on the polarization sensitive array signal model, introducing the Euler rotation transformation method which used to realize the conversion between Cartesian coordinates, and achieving the global Cartesian coordinate conversion of picket polarization pattern placed conical conformal array, finally establishing the received signal model of conical conformal array.Secondly, combined with the received signal model of conical conformal array, two types of independent sources DOA estimation algorithm are introduced: the former is MUSIC algorithm which based on the noise subspace, while the latter is ESPRIT algorithm based on signal subspace,and a brief analysis of the affection that generated by signal to noise rate(SNR), snapshots and source correlation coefficient via the simulation results under different conditions. Based on the above estimation model, the MUSIC and ESPRIT algorithm based on the conical conformal array are compared together through the following respects: SNR, snapshots and computational complexity.Last of all, based on the separate letter estimation, the application of two kinds of decorrelation algorithm on coherent sources estimation under the conical conformal array are considered : the first is spatial smoothing technology, the second is matrix decomposition algorithm,and analyzing the performance and feasibility of the decorrelation algorithms on the perspective of the theoretical and simulation. Based on this, the performance of the discussed algorithms is compared through simulation ananlysis in the view of SNR, snapshots, smooth number, source correlation coefficient and the amount of computation, which assessed the performance relationship of those decorrelation algorithms.