Multiple broad-band source location using steered covariance matrices

Abstract

Absfmt-This paper presents an approsch for reducing the threshold observation time required to achieve high-resolution localization of multiple broad-band sources. The proposed techniques are based on a space-time statistic called the steered covariance matrix (STCM). The STCM, like the well-known cross-spectral density matrix (CSDM), has asymptotic properties which facilitate h%h-resolutlw source iocalization. In broad-band settings, however. the STCM has the advantage that it can be estimated with much greater statistical stability than the CSDM. In this paper, the STCM Is used in coqjunctbn with minimum variance and linear predktive spectnl estimation to obtain the steered minimum variance (STMV) and steered linear pndition (STLP) methods. Analytical and simulation results are presented which suggest the STMV and STLP methods exhibit lower threshoid observation times than their CSDM-based counterparts.

Beamforming with a Limited Number of Snapshots

“…The Rayleigh limit of angular resolution of a uniform linear array of n elements is approximately 2/(n -1) radians (Krolik & Swingler, 1989). In particular, for n = 100 sensors, the Rayleigh limit is approximately 1.15750, which is less than the 20 spacing just mentioned.…”

Robust adpative beamforming for triplet sonar arrays

“…(steered covariance matrix) [8] 는 다음과 같은 형태로 표 현된다. 제안하는 기법에서 카디오이드 빔형성은 Hughes [3] 의 기법을 적용하였기 때문에 회전각 오차에 대한 카디오이드 빔 좌우 구분 성능은 Hughes의 기법과 거의 동일하다.…”

Sparse covariance fitting method for direction of arrival estimation of uncorrelated wideband signals

“…Section IV concludes the paper. DFT with a sufficient number of frequency bins as in [2], [3] or narrowband filters followed by additional conversion to baseband as in [6]. …”

“…Such methods are known as coherent methods. Another conventional method [2] calculates the spatial spectra of all M signals and combines them to obtain a new spectrum that is used to estimate the directions of arrival (DoAs). This method belongs to the noncoherent group of wideband DoA methods.…”

“…Here we extend the narrowband model from [10], [11] to a wideband model and derive a new wideband direction of arrival estimation method which is the novelty of this paper. The received wideband signal is first decomposed into a set of independent narrowband signals using Discrete Fourier Transform (DFT) ( [2], [3]) or narrowband filters ( [6]). For each of the different narrowband signals the covariance matrix is calculated and a sparse narrowband model based on individual sparsity is created.…”