Modified short multipath insensitive code loop discriminator

Several studies have been carried out to minimize the multipath error effects in Global Positioning System (GPS) receiver. Most of these studies achieve an acceptable performance with medium and long relative delay multipaths. In this paper we propose a Modified Short Multipath Insensitive Code Loop Discriminator (MSMICLD) using an Early minus Late (E-L) envelope discriminator function. The proposed discriminator is insensitive to short multipaths that have a relative delay less than 0.5 chips. The MSMICLD is modeled using MATLAB and its performance is evaluated with and without multipaths for three different types of receivers; infinite pre-correlation (front-end) bandwidth (BW), 2 MHz pre-correlation BW, and 8 MHz pre-correlation BW. Moreover, the performance of the proposed MSMICLD is compared with the conventional SMICLD. Simulation results show that the MSMICLD has the ability to mitigate the short multipaths effect in the three cases. The obtained results also show that for in-phase multipaths, the performance of the proposed discriminator outperforms the conventional SMICLD with a lower computational load.