Application Of Real Time Parallel Signal Processing Technique In Active Acoustic Simulating System

Along with the development of the ocean science and technology, the intelligent moving targets of underwater such as the submarine, torpedo, mine, ROV, have been developed dramatically: the period of upgrade is shortened and the performance is advanced obviously. How to verify the performance of the intelligent moving targets of underwater? How to evaluate the new generation? In the background, a active acoustic simulating system has been designed which is based on the SHARC parallel signal processing technique. The system is used to verify the performance of a certain intelligent weapon of underwater. The main task is to provide the verifying equipment which is used for sea experiment of the certain intelligent weapon of underwater.There are three main aspects: detecting signal, extracting characters and resending echoes. In detecting signal, the input signal is preprocessed by the filter which is built by the method of overlapping and reserving. Then, the one-order recursive filtering method is used to evaluate various noise of background and to compare the length of pulse and period of signal. In the system, the main characters of signal are the frequency and intensity. The frequency of signal is measured by cosine function. The intensity of signal is measured by square detection. Resending echoes involve sound radiation, highlights of echoes and Doppler frequency-shift.At present, it is considered that the development of micro-electronics have being close to the physical limitation. So the parallel signal processing technique is urgently. The main characters of high speed and real time DSP chip are adopting parallel signal processing technique, involving in-chip and inter-chip. The parallel processing in the chip include SIMD,MIMD,VLIW and so on. That of inter-chip include loose coupling and tight coupling. This system adopts the loose inter-chip coupling which is composed by 4 SHARCs. Every functional arithmetic is reasonable distributed to every DSP. In order to get the most efficiency, the system is constructed by suitable data package and dealt with 8 steps full pipelining.