UWB Channel Sounding and Modeling for UAV Air-to-Ground Propagation Channels

Abstract

Unmanned aerial vehicles (UAVs) are expected to be used extensively in the near future in applications such as aerial surveillance, transportation, and disaster assistance. The conditions under which UAVs operate are different from those of conventional piloted aircrafts. This necessitates development of new air-to-ground (AG) propagation channel models for UAVs. To our best knowledge, there are limited studies in the literature on sounding and modeling of ultrawideband (UWB) AG propagation channels. In this work, comprehensive UWB measurements are conducted for various UAV communication scenarios using Time Domain P410 UWB kits. Both time and frequency domain analysis of the measured data are carried out. Based on the measured data, stochastic path loss and multipath channel models are developed to characterize AG UWB propagation channels.

A Survey of Channel Modeling for UAV Communications

“…In [45] and [46], delay spread resolution was in micro-seconds for suburban environment. In [47], excess delay and RMS delay spread were of the order of nano-seconds for a foliage environment. In this case, channel impulse response was obtained by Clean algorithm.…”

“…When the UAV altitude increases above the breakpoint level the path loss is similar to free space propagation because the first Fresnel zone was cleared. In [47], the effect of UAV altitude and the optimal placement of the ground receiver for path loss was stochastically modeled for both static and mobile UAVs in both open field and suburban scenarios. Foliage losses and Doppler frequency shift were taken into account.…”

“…In [47], the measurement campaign was conducted for open and suburban spaces on the campus of Florida International University using an ultra-wideband (UWB) channel sounding radio. In the first scenario, the receiver was placed under the tree canopy at 1.5 m above the ground.…”

“…Rayleigh channel distribution is a special case of Nakagami-m. In [47], magnitudes of individual multipath components were collected for different time delay bins and modeled by the Nakagami-m distribution. In this case, mean and standard deviation of the m parameter were empirically estimated.…”

Low Altitude UAV Air-to-Ground Channel Measurement and Modeling in Semiurban Environments

“…In [14], the aircraft was flying circularly around the base station to investigate the impact of the angle. In [11,15], ray tracing methods were applied to investigate the propagation channel in urban environments, and in [16] wideband measurements were conducted with a UAV being fixed at a certain position, which depicts the influence of the ground. In [17], narrowband and wideband channel measurements were introduced using LTE signals.…”