Impact of Ultra Wide-Band Antennas on Communications in a Spatial Cannel

Aim of this contribution is to study the impact of typical ultra-wideband (UWB) antennas for communications over a spatial wireless channel. In order to adequately consider the directivity properties of real antennas, out analysis is suitably based on a ray tracing UWB channel model since this reflects the dependence on the angle of arrival (AoA) and angle of departure (AoD) of any multipath. A mathematical framework is given which also allows an optimization of such an UWB multiple input multiple output (MIMO) system using different types of transmitting and receiving antennas on behalf of idealistic omnidirectional ones. Beside the angle dependence, the antenna transfer functions are without doubt frequency dependent on such a large UWB bandwidth, so that they will be evaluated with suitable analog design specialized tools for the fast and accurate three-dimensional electromagnetic simulation of high frequency circuits. Simulation results allowing concrete guidelines on the antenna influence are provided in the last section of this paper