Abstract: UWB (Ultra Wide Band) communication is a novel communication technique,but it interferes other communication systems. We use the efficient ray tracing method to describe the UWB indoor environments. The ray tracing model is used to simulate the propagation environment of a typical house. The time and spatial properties of the UWB indoor channel are presented by using ray tracing, which include RMS（Root-Mean-Squared）, distribution of ray energy and channel impulse response. Based on the UWBs properties, the influence of the UWB signal interference on the GPS (Global Positioning System) signal is estimated, and some UWB properties can be adjusted to make the GPS applications practicably.

Key words: root-mean-squared(RMS) delay, interference, ultra wide band(UWB) communication, ray tracing method