Two-Dimensional DOA Estimation for Coherently Distributed Sources with Symmetric Properties in Crossed Arrays

Abstract

In this paper, a novel algorithm is proposed for the two-dimensional (2D) central direction-of-arrival (DOA) estimation of coherently distributed (CD) sources. Specifically, we focus on a centro-symmetric crossed array consisting of two uniform linear arrays (ULAs). Unlike the conventional low-complexity methods using the one-order Taylor series approximation to obtain the approximate rotational invariance relation, we first prove the symmetric property of angular signal distributed weight vectors of the CD source for an arbitrary centrosymmetric array, and then use this property to establish two generalized rotational invariance relations inside the array manifolds in the two ULAs. Making use of such relations, the central elevation and azimuth DOAs are obtained by employing a polynomial-root-based search-free approach, respectively. Finally, simple parameter matching is accomplished by searching for the minimums of the cost function of the estimated 2D angular parameters. When compared with the existing low-complexity methods, the proposed algorithm can greatly improve estimation accuracy without significant increment in computation complexity. Moreover, it performs independently of the deterministic angular distributed function. Simulation results are presented to illustrate the performance of the proposed algorithm.

Direction-of-Arrival Estimation for 2D Coherently Distributed Sources with Nested Array Based on Matrix Reconstruction

“…Lee et al [19] have proposed a sequential one-dimensional searching algorithm based on double uniform circular arrays (DUCA). In [20], DOAs can be estimated from proposed symmetric properties of a centrosymmetric crossed array. Considering CD sources are correlated with each other, Wu et al [21] have made a proposition of a 2D estimator utilizing DPLA.…”

“…(i) ough DOA estimations for 2D CD sources are presented in [12][13][14][15][16][17][18][19][20][21][22], the arrays are all uniform. In [27,28,30,32], DOA estimators for 2D sources using sparse arrays are considered, which aim at point sources.…”

On Spatial Smoothing for DOA Estimation of 2D Coherently Distributed Sources with Double Parallel Linear Arrays

“…It is a common characteristic that utilizing rotational invariance relationships derived by Taylor approximation to generalized steering vectors, the nominal elevation and azimuth are solved under ESPRIT or modified propagator framework. The authors of [21] have proposed a method using a centro-symmetric crossed array, where DOAs are obtained through the symmetric properties of the special array. Utilizing two closely spaced parallel linear arrays and L-shape arrays, two estimators for CD noncircular signals are proposed in [22,23] which exhibit better accuracy and resolution compared with circular signals.…”

“…In [1,[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], CD sources have been regarded as uncorrelated with each other; estimators cannot be applied for CD sources which are correlated. In [24], though 1D CD sources correlated with each other are discussed, but the general model of coherent CD sources has not been presented.…”