Design of microstrip antennas for channel characterization receiver system

Summary form only given. The paper presents the design methodology and simulation results of various microstrip antennas intended to be used in the vector channel sounder under development in the Mobile Radiocommunications Laboratory. Extraction of multipath signal direction of arrival (DoA) information during wideband channel characterization requires spatially diversified reception of impinging waves. Sampling of the incident field in several locations enables one to resolve the direction of arrival of multipath signals by considering the phase difference between samples. In order to determine the DoA in three dimensions (when both azimuth and elevation angle are essential), the measurement system requires samples from non-collinear points. In this case, incident field sampling is performed by a three-dimensional (spherical) or by a two-dimensional (planar or circular) antenna array. On the other hand, for DoA resolving in two dimensions (thus, when just the azimuth angle is adequate for channel characterization) the points can be placed in a straight line, as in a linear array. In order to conclude on the type and the exact shape of the elementary antenna that will be used in the channel sounder's receiving array, several design scenarios are considered based on the properties of the specific channel characterization application. The scenarios include single layered and multi layered microstrip patch antennas, experimentation on parasitic element influence, and investigation of different feeding and bandwidth enhancement techniques. Finally, an estimation of mutual coupling influence is presented by simulating. neighboring elementary antennas in patterns similar to those that would be encountered in either a linear or a two-dimensional array.