Number & DOA of Coherent Signals Determination by Eigenvector Matrix Operation - A New Method for Estimating the Direction-of-Arrival and Determining

The research of signal parameter estimation using antennaarray have been extensively attended for decades. In arrayprocessing, the estimation of DOA( Direction of Arrival ) or thedetermination of number of signals plays an important role in manyapplications such as in sonar, radar, and seismic measurement.However, the concept of most known algorithms is assuming thesignals are uncorrelated. In practice, the transmitting signals areusually reflected or refracted by mountains, buildings or otherimpediments. It will cause multi-path propagation as highlycorrelated or coherent signals are received on thesensor.Therefore, rank deficiency of signal covariance matrix willbe raised.It will cause the usual eigenvalue-detecting method goingfailed. In this book, we propose a new method for the rankdeficient issue. For avoiding the confusion caused by the unknownlength of subarray, we use some operations of the eigenvectormatrix to form a new matrix. Besides, we can find out the number ofsignals by counting the non-zero eigenvalues of the covariancematrix of this new matrix. Furthermore, we also can categorize thecoherent signals into different groups for their coherence.