Mapping and overlapping based carrier frequency searching technique for rapid GNSS long PN-code acquisition

Abstract

In global navigation satellite systems (GNSS), because of the long period and high chip rate of long pseudo-noise (PN) code, the rapid acquisition is hard to accomplish. To speed up search process, in the paper, a mapping and overlapping based carrier frequency searching technique is proposed. By mapping incoming signals of the same interval to different carrier frequency cells and overlapping together the mapped incoming signals that correspond to the same code phase, the technique reduces the number of the cells to be searched. The effect of the technique on detection and mean acquisition time performance is analyzed. It is shown that the technique reduces the cells to be searched and shortens mean acquisition time at the expense of degrading detection performance. The technique is fit to the previously published acquisition methods and is capable of improving their mean acquisition time performance. Numerical and simulation results validate the analysis.