Multipath
Multipath affects the desired signal by distorting both the phase and the amplitude. This can result in a lost signal or a distortion in the TOA of the desired signal. Multipath is divided into two categories: specular and diffuse. Specular multipath generally affects the system the most, resulting in more errors. Diffuse multipath is more noise-like and is generally much lower in power. The Rayleigh criterion is used to determine if the diffuse multipath needs to be included in the analysis. The curvature of the earth can affect the analysis for very long-distance multipath. One of the ways to reduce the effects of multipath is to use leading edge tracking so that most of the multipath is ignored. Some approaches for determining multipath effects include vector analysis and power summation. Several methods of multipath mitigation were discussed, including using multiple antennas for antenna diversity.
Multipath, Page 1 of 2
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