Repeater Effect Suppression Method for TDOA algorithm in CDMA system

This paper discusses an improved method for location in CDMA based cellular communication system. The Time Difference of Arrival (TDOA) technique is one of the most promising location techniques for cellular communication system. This technique is based on estimating the difference in the arrival time of the signal from the source at multiple receivers. In digital communication systems, a repeater is a device that receives a digital signal on an electromagnetic or optical transmission medium and regenerates the signal along the next leg of the medium. Repeaters are commonly used by commercial and amateur radio operators to extend signals in the radio frequency range from one receiver to another. This research analyzes the performance of TDOA techniques in the CDMA system. We consider effect of repeater and it was also found that performance degrades quite gradually with increasing the number of repeater. We adopt a enhanced TDOA technique subtracting the repeater signal from received signal at a handset. We showed that the proposed algorithm has improved performance in TDOA locating system.