improving long pn-code acquisition in the presence of doppler frequency shifts

wireless communication is the major form of connection nowadays. in most cases it exploits the benefits of the spread spectrum techniques to overcome channel introduced corruptions like doppler residual frequency, noise, interference and jamming. these techniques also enhance the security and quality of the link. using long spreading pseudo-noise codes provides further security for the link though its acquisition is challenging. in this paper we propose enhanced dual folding method for acquiring long codes in high doppler scenarios. two main criteria of an acquisition algorithm i.e. probability of detection and mean acquisition time is theoretically and numerically obtained for the proposed method. the proposed method's performance is simulated for two doppler residual frequencies and is compared with a similar technique of long code acquisition which confirms the success of the proposed method in tolerating high doppler in comparison with the similar technique. the simulation results agree well with the theoretical equations.