Free-Field Measurements of the Electrical Properties of Soil Using the Measured Reflection Coefficient at Normal Incidence and Multilayer Analysis.

摘要

A near-earth propagation measurements program was initiated at the Institute for Telecommunication Sciences (NTIA/ITS) Table Mountain Field Site (TMFS) in May 2010 under the sponsorship of the Table Mountain Research Project. We continued this program in June 2011 with a second set of measurements. The purpose of these efforts was to determine the ground constants at the TMFS. While comparing measured and modeled results, questions arose about the assumed dielectric permittivity and conductivity of the soil at the TMFS. These ground constants can have a significant influence on RF propagation predictions near the ground and need to be accurately characterized. This led to the development of the measurement system described in this report. The system described in Section 2 of this report performs reflection coefficient measurements of the ground surface at various locations at TMFS using a dual-ridged horn antenna. This analysis will concentrate on two sets of measurements. The first was conducted in May 2010 along Plateau Road at various road positions. The second set of measurements, taken in June 2011, was performed in the parking lot at Building A4 with a blacktop surface using stepped-frequency reflection coefficient measurements over a band of interest extending from approximately 700 MHz to 6000 MHz.