Beamspace approach for detection of the number of coherent sources

Abstract

A beamspace approach is presented to detect the multiplicity of impinging sources on the sensor array for the direction of arrival estimation problem. The method applies to the coherent signals and can also be used to detect the presence of interfering multipath signal. In many applications, the signal to noise ratio is not sufficient to resolve multiple sources with close spatial frequencies. The suggested method is to detect the presence of an interfering secondary source which can not be possibly resolved.

Credibility Test for Frequency Estimation of Sinusoid Using Chebyshev’s Inequality

“…For some methods, estimation of frequency is the precondition for estimating the other parameters of sinusoid signals [1] as well as frequency estimation of modulated signals [2,3]. Many algorithms have been proposed for estimation of frequency from received signals [4][5][6][7][8][9][10][11][12]. Performance evaluation of frequency estimation algorithms is also a key operation in practical signal processing systems and can be considered from two points of view.…”

“…As IEEE 1990.6 for cognitive radio (CR) [15] expressed, the modulation recognition confidence rating is regarded as additional output information in some civilian signal processing devices; an example is Agilent's option MR1 for E3238S signal detection and monitoring systems. Nevertheless, the detailed method of evaluating the reliability of modulation recognition is not described in both [10,11]. Fehske et al [16] defined the half value of the maximum and the second maximum output of the back propagation-(BP-) based classifier as the confidence metric of modulation classifying results for CR.…”