A Joint Acquisition Algorithm Based On Primary Code And Secondary Code For Gnss Signals

The Hierarchical code structure perfectly solves the contradiction between acquisition complexity and correlation performance and it will be a good solution for future GNSS signal design such as Beidou system. Aiming at shortage of current acquisition algorithms because of limited coherent integration time when for weak signals situations, this paper proposes a new acquisition algorithm which jointly uses the primary code and secondary code together. The characteristic code is introduced to solve the problems induced by longer secondary codes. Firstly, the current GNSS signals with secondary codes are given. Secondly, the definition and obtain procedure of characteristic codes are presented. Thirdly, the concrete acquisition algorithms are listed for various circumstances and the calculation amount is given. Finally, the experiments are carried out and the conclusion is drawn.