DETECTION: A NEW APPROACH.

A method for the detection of the number of signals in array processing is proposed. This technique can provide the number of signals irrespective of the signal-to-noise ratio, whereas existing detection techniques fail to perform at low signal-to-noise ratios even asymptotically. The asymptotic error performance of the proposed technique is studied, and it is shown that the probability of error is nearly zero. An objective criterion is given to obtain the number of signals for the case in which the number of snapshots are finite. The concept of detectability is introduced, and a methodology is developed to obtain the detectability of an array system together with number of signals.