Theoretical ground reflection model for UWB communication systems

In this paper, the theoretical ground reflection model for UWB communication systems is proposed. The passband rectangular pulse with specific center frequency and bandwidth is used as the transmitted signal. The complex form Friis' transmission formula is applied for the UWB ground reflection channel. The received signal is evaluated. The UWB path loss is defined as the ratio between the maximum amplitude of the transmitted and received signal waveforms. The closed form path loss expression is derived. For the data processing, the path loss and rms delay spread of the ground reflection model are considered for the 1.00, 0.10 and 0.01 m antenna heights. The double linear regression for the path loss is modeled by using the first Fresnel zone and MMSE break points. The rms delay spread as a function of the antenna height and the path loss is investigated. The characteristics of the path loss and rms delay spread are discussed in the paper.