Country-specific Ground-based Bistatic Radar Clutter Analysis of Rural Environments

Abstract

This thesis presents a novel statistical analysis of bistatic radar rural ground clutter for different terrain types of German rural environments under low grazing angles. A country-specific clutter analysis for subgroups of rural environments rather than for the rural environment as a whole will be presented. Therefore, the rural environment is divided into four dominant subgroup terrain types, namely fields with low vegetation, fields with high vegetation, plantations of small trees and forest environments, representing a typical rural German or even Central European environment. The thesis will present the bistatic clutter characteristics for both the summer and the winter vegetation. Therefore, bistatic measurement campaigns have been carried out during the summer 2019 and the winter of 2019/20 in the aforementioned four different rural terrain types. The measurements were carried out according to a designed bistatic measurement methodology to obtain comparable results and to be used for different radar applications in the radar relevant X-band at a center frequency of 8.85 GHz and over a bandwidth of 100 MHz, according to available transmit permissions. The distinction of the rural terrain into different subgroups enables a more precise and accurate clutter analysis and modeling of the statistical properties as will be shown in the presented results. A clear separation of the different types of rural terrain and the influence of the seasons was worked out. Additionally, model functions for the relevant parameters, characterizing the the bistatic clutter, are presented for their analytical description. The statistical properties are derived from the clutter regions of processed range-Doppler domain data, using an improved range-Doppler processing approach, for each of the four terrain types and the corresponding seasons. The data basis for the clutter analysis are the processed range-Doppler maps from the bistatic radar measurements using a dual-channel measurement approach, with a separate reference and surveillance channel. According to the authors’ current knowledge, a similar investigation based on real bistatic radar measurement data with the division into terrain subgroups and additionally for different season has not yet been carried out and published for a German rural environment. The presented data and results therefore have a significant impact on the research field of bistatic ground clutter, in which there are currently only very few results in the frequency range discussed in this thesis.