Improvement of signal-to-noise ratio at the single-sensor for narrow-band signals in a partially correlated noise field

Abstract

This paper deals with the development of a processing technique that will improve the signal-to-noise ratio at the single sensor for a received signal that is embodied in a partially correlated noise field. The approach of this study is unique in that the noise will be treated as being nonwhite and partially correlated. The concept of the proposed development is based on the time interval over which the temporal coherence or correlation properties of a noise field are defined. For narrow-band signals, the associated temporal coherence period is much longer than the correlation time interval of the anisotropic noise field. Thus a coherent integration of discontinuous segments of received signals will enhance the signal-to-noise ratio at the sensor by lowering the correlation properties of the associated nonwhite noise. Reconstruction by the proposed technique of the narrow-band signal time series with improved signal-to-noise ratio at the sensor will allow the use of the existing high resolution techniques to be utilized more effectively by lowering their threshold values in order to detect very weak signals. The intention here is to integrate the characteristics of the real anisotropic noise field during the preliminary processing stages of the array-sensor received signals.