An All Digital Spread-Spectrum Transceiver

A novel all digital and practical spread-spectrum transceiver used in obvious Doppler shift conditions is presented. 16 parallel channels are used to acquire the PN sequence simultaneously, reducing the acquisition time to 1/16 of that in the single channel mode. The Doppler effect on the processing gain is eliminated with the FFT algorithm. Node synchronization in Viterbi decoding is achieved rapidly using the Barker sequence as the head of interleaving frame. Fast-synchronization in PN code and the carrier is thereby achieved.