A novel DS/SS code acquisition technique based on seed accumulation of sequence generator

Abstract

The sequential estimation (SE) proposed by R.B. Ward (see IEEE Trans. Commun., vol.COM-13, p.474-83, 1965) for rapid acquisition of pseudonoise (PN) sequences works well only at moderate signal-to-noise ratios (SNRs). A seed accumulating sequential estimation (SASE) method based on accumulating seeds of the received PN sequence is proposed, which performs well at low SNR also. The mean acquisition time of the proposed SASE method is derived by the generating function flow graph technique, and correct chip, detection and false alarm probabilities are obtained. Finally, numerical results show that the proposed SASE dramatically performs better than the conventional SE at low SNR and the improvement becomes larger as the period of the PN sequence increases.