Multipath mitigation technique in RF ranging

Radio Frequency (RF) ranging systems typically use a measurement of the signal´s phase to provide the range. There are many problems associated with this technique in determining the range. Multipath has a dominant effect on the phase measurement, especially when a high level of accuracy is required. This paper introduces a multipath mitigation algorithm for a spread spectrum RF ranging system, employing the frequency hopping (FH) technique. Some models are built to present the mathematical relationship between the direct signals, the reflected signals, and the composite signals. The algorithm allows the precise distance of the direct path to be determined. This technique could cancel the effect of multipath in a two-ray environment