Joint estimation of DoD, time-delay, and DoA for high-resolution channel sounding

The detailed knowledge of the directional characteristics of the mobile radio channel is required to develop directional channel models and to design efficient smart antenna concepts for future mobile radio systems. In this paper, we present a high-resolution estimation scheme for the directional channel parameters from dual antenna array based channel sounding measurements. Since 360° azimuth coverage seems reasonable at the mobile station (MS), the utilization of a circular uniform beam antenna array at this place is proposed. Moreover, a transformation is described making this array suitable for high resolution angle estimation with ESPRIT. With this approach, the joint estimation of direction of departure, time-delay, and direction of arrival using 3-D Unitary ESPRIT is derived. Finally, we propose a procedure for the model order estimation and discuss some calibration issues