| 摘要 |
<p>In a sonar receiver, received digitized sounding signals (rsdo-rsd3O) are processed into beamformed signals (rb0-rb30) corresponding to different azimuth angles. Thereafter, quadrature and in-phase components are decoded, each comprising N copies of the predetermined code as result of defining each code element of a predetermined code by the N periods of the sounding signal. Then a correlation function is computed separately for each individual copy of the code, i.e. the process is divided into number of steps, which is equal to the number of data points (signal periods) per code element. After correlation functions of all individual copies of the code are computed, the results are combined (aligned) and the moving average filter is applied resulting in an overall correlation function. This kind of processing, instead of computing correlation function straightforwardly, approach allows to obtain more efficient computation, i.e. less arithmetic operations have to be performed in order to obtain the final result. As result less computation capacity is needed for real-time processing.</p> |
