Multipath Fading Validation Experiment Based on SDR USRP

The multipath fading of radio signals is hard to verify and intuitively observe. In this paper, a combined wireless communication system by software simulation platform (Simulink) and hardware devices (SDR-USRP) is established, by adapting 3 multipath propagating modes: multi-cable transmission, line-of-sight radio propagation, non-line-of-sight radio propagation, to test the question “does multipath propagating inevitably result in signal fading?”. The envelope of the captured physical signal is then derived by using Local Maximum Method, and further the envelope samples are used for fading channel modeling by statistical data fitting method. A conclusion “multipath propagating does not always cause signal fading” can also be draw by this experiment. Meanwhile, the envelope of received mixed signal after transmitting over the nun-line-of-sight multipath channel following the Rayleigh distribution is then tested, hence a “visible” multipath fading channel is implemented.