S.A.W. sidelobe reduction filter for Barker codes

A description is presented of an approach which allows the mean sidelobe power, averaged over a range of Doppler frequencies, to be minimized. In addition, a complementary approach is described which is explicitly intended to give a high main to peak sidelobe ratio. It is not mathematically straightforward to maximize this ratio formally. The approach is, therefore, more heuristic in nature, but it does produce very useful results. Finally, experimental results are presented on a surface wave compression filter for a 7-bit Barker code, with a weighting designed by the second approach. As regards sidelobe level at zero Doppler the second method described is considerably more successful in reducing the peak sidelobe level. The performance of the first method, judged by the peak sidelobe level is less impressive, as can be seen by comparing results for the 7-bit code.