Digital Alias-free Signal Processing

17

Spatial Data Acquisition and Processing

The topic of spatial signal processing is now approached to draw attention to the fact that the anti-aliasing signal processing technology described in this book was initially developed for handling signals in the time and frequency domains but is also applicable in the area of spatial signal processing vital for all types of radar systems. While various types of problems could be attacked on the basis of this technology, the following discussions are focused on the issue of the complexity reduction of large-aperture antenna arrays. Specifically, the potential of pseudo-randomization of large-aperture antenna arrays is considered and evaluated as an approach applicable for reducing the number of sensors in the array. To achieve good results in this area, it is suggested that the positive experience obtained at signal processing in the time domain can be adjusted to the specifics of spatial signal processing. The rationale of this approach is based on the fact that irregular taking of signal sample values in the time domain is equivalent to the irregular spacing of sensors in the array.

Although historically the problems of randomizing the temporal signal processing have received much more attention than the analogous problems of spatial data acquisition and processing, the potential usefulness of deliberate randomization in this area has not been overlooked. A number of publications provide evidence of this. However, at first glance, these ...