Code design and performance characterization for code multiplexed imaging

A new sonar imaging technique which uses coded waveforms to project different sound signals in different directions has bee proposed. In this context, the problem of creating a set of frequency-hopped code words that have mutually small correlation properties has arisen. The design and performance characterization of frequency-hopped signals for multibeam sonar imaging are discussed. The two special cases considered are the fully coherent case, and the incoherent case when medium perturbations destroy the phase coherence. Two systematic design techniques are presented that are based on elements of the Galois field GF(p), where p is a prime number. One technique uses first-order Reed-Solomon code words in order to generate p code words of length p-1. The other technique is an empirical design technique which generates p-1 code words of length p