Abstract:

The quasi synchronous frequency hopping communication system based on frequency hopping sequence with low hit zone has lower multiple access interference. The existing one dimensional frequency hopping sequences with low hit zone is expanded to two dimensional timefrequency hopping sequences. Two construction methods of frequency hopping sequence set with two dimensional time frequency low hit zone are presented. The construction methods are based on Welch Costas array and Golomb Costas array respectively. And by the method of sequence cyclic shift, the frequency hopping sequence sets with the two dimensional timefrequency low hit zone can be obtained. The newly constructed frequency hopping sequence sets reach the theory bound formed by two dimensional periodic hamming auto correlation and cross correlation function of frequency hopping sequence. Meanwhile, it results in the optimal autocorrelation and cross correlation properties in the two dimensional timefrequency low hit zone.