Simulation results of ranging performance in two-ray multipath model

In this paper, we analyze the ranging performance of chirp spread spectrum (CSS) in two-ray multipath indoor environment. Reflected multipath signals will affect the received signal in the receiver deforming the correlation shape and thus will alter the real value of ranging. In indoor environment, conventional methods for tracking positions are unsuccessful due to the harsh multipath signals. Thus, IEEE 802.15.4a was defined for wireless local area network capable of local high speed communication and precise ranging. Here CSS is used as a physical layer because of their robustness to multipath indoor environment. We study the ranging error of CSS caused by multipath signals. We simulate the ranging error by MATLAB. And we assume the two-ray multipath model as the indoor wireless channel and measure the ranging values using delay lock loop which utilizes null tracking strategy.