Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Quickest Detection of a Random Signal in Background Noise Using a Sensor Array | EURASIP Journal on Applied Signal Processing 2005 1 13-24 2005 Hindawi Publishing Corporation Quickest Detection of a Random Signal in Background Noise Using a Sensor Array Taragay Oskiper Zargis Medical Corp. Princeton NJ 08540 USA Email toskiper@ H. Vincent Poor Department of Electrical Engineering Princeton University Princeton NJ 08544 USA Email poor@ Received 2 December 2003 Revised 21 June 2004 The problem of detecting the onset of a signal impinging at an unknown angle on a sensor array is considered. An algorithm based on parallel CUSUM tests matched to each of a set of discrete beamforming angles is proposed. Analytical approximations are developed for the mean time between false alarms and for the detection delay of this algorithm. Simulations are included to verily the results of this analysis. Keywords and phrases sensor array quickest detection angle-of-arrival estimation. 1. INTRODUCTION In this paper we consider the problem of detecting as soon as possible a target that appears abruptly and at an unknown angle in a sensor array. This is a problem that arises in a number of applications including radar sonar and communications. For a fixed angle of incidence and known signal and noise distributions this is a classical problem in statistical change detection and can be solved for example by the Page s CUSUM algorithm. However here we consider the situation in which the angle of incidence and the signal and noise statistics are unknown. In this case alternatives to the classic CUSUM must be considered and a number of such methods have been developed for such problems 1 2 3 4 5 . Here we use an approach motivated by Nikiforov 4 in which we discretize the set of incidence angles and run parallel change-detection algorithms each one matched to a beamformer pointed at a particular angle. The presence of a signal is announced the first time the test statistic associated with any of these parallel algorithms crosses a threshold. The .
