A Signal Processing Framework for MIMO UWB Channels with Real Antennas in Real Environments

An open issue from a signal processing perspective is the adequate inclusion of real UWB antennas, and, in particular antenna array´s, in an overall channel model for communication and localization purposes. The knowledge of several antenna properties, like polarization, directivity and phase patterns, and mutual coupling between neighbouring antennas -on both the transmit and receive side -are required for optimizing overall system performance, e.g. a low BER for a given data rate or high localization accuracy for a given environment. This holds especially true for UWB signals, since all antenna parameters become frequency dependent for such large bandwidth so that their impact on the systems performance is a-priori not known. In our contribution, we present a signal processing framework where the antennas impulse responses are completely determined by an electromagnetic field simulator and the propagation pathes are calculated by ray tracing. The ray tracer allows to determine the angle of arrival (AoA) and angle of departure (AoD) of each multipath and in cooperation with the field simulator the overall systems impulse response for a real antenna setup in a real environment becomes computable. Some results will be presented and discussed at the end of the paper.