Increasing Ultrasonic Array Data Acquisition Rate through the use of Kasami Codes and the Maximum Entropy Method

摘要

We suggest using sets of pseudo-orthogonal code with antenna arrays working in Full Matrix Capture (FMC) mode, to increase the rate of data acquisition. This allows the use of signals comprised of phase-manipulated Kasami sequences, specifically developed for CMDA technology. The use of the Maximum Entropy Method (MEM) for decoding signals in lieu of matched filtration allows us to reduce noise level and increase time resolution in reflectors’ image. Additionally, to reduce noise level by more than 6 dB we suggest the use of various Kasami sequences for each position of an antenna array. Numerical and model experiments demonstrate the efficacy of the proposed approach.