The design and performance of transversal filters for the sidelobe reduction of pulses compressed from combined Barker phase codes

The high temporal sidelobes of compressed combined Barker codes can be reduced using minimum-square-error transversal spiking filters. Very large (40 to 60 dB) peakto sidelobe ratios may be obtained for words up to 169 bits long using transversal filters which are only several hundred bits long. The effect of a Doppler frequency shift of the signal is analysed and a cross-ambiguity diagram is presented for a 52-bit word and a 200-bit filter. The influence of noise and manufacturing tolerance is also considered, and, finally, improvements due to a further shaping of the output are detailed.