Low VHF Channel Measurements and Simulations in Indoor and Outdoor Scenarios

摘要

Abstract : The lower VHF band has potential for low power, short-range communications, as well as for geolocation applications, in both indoor and urban environments. Most prior work at low VHF focuses on longer range path loss modeling. In this report, we study indoor/outdoor near-ground scenarios through experiments and electromagnetic wave propagation simulations for both line-of-sight (LOS) and non-LOS (NLOS) cases, at ranges up to 200 meters. Mounting our receiver on a robotic platform enabled the collection of thousands of measurements over an extended indoor/outdoor test area. We measure the channel transfer function with pulse and tone probe signals. Based on statistical tests, we show that the measured channels have a nearly ideal scalar attenuation and delay transfer function, with minimal phase distortion. Compared with higher VHF and above, the measured short-range VHF channels do not exhibit small-scale fading, which simplifies communications receiver signal processing, and enables phase and amplitude based geolocation techniques.