ABSTRACT

Array signal processing is concerned with the application of signal processing techniques to the outputs from a spatially distributed array of sensors. The power of array processing lies in the possibility of achieving improvements in measured Signal-to-Noise Ratio (SNR) as compared to that attainable with a single input sensor. The spatial dimension introduced by processing a distributed array of sensors allows directional discrimination between signals and interference. Sensor arrays are used in many applications including radar, sonar, seismology and tomography. Physically, there are many differences between the various arrays, ranging from the form of energy transported by the wave, to the type of sensors, to the physical dimensions of the array. The array can also be viewed as a mechanism for improving SNR by averaging many sensor measurements together. The chapter explains adaptive arrays are to allow flexible response in the absence of prior information and in the presence of temporal, and in this case spatial, fluctuations.