Signal and Image Processing Seminar

In wireless communications, smart antenna systems that use multiple antennas at the base station can increase capacity and coverage by exploiting the spatial dimension in signal processing. However, the channel propagation effects that are nonexistent or different on a wired system pose significant difficulties for space-time signal processing. Characterization and modeling of vector propagation channels are important for the smart antenna system design and adaptive array algorithm development.

In this talk, we focus on the variation of vector channel parameters under environmental and cell-design factors. The environmental factors include multipath propagation and relative motion between the base station and the mobile terminal. For the cell-design factors, we consider the base station antenna deployment. We present the experimental results obtained by using a real-time smart antenna system in realistic wireless scenarios. In particular, we characterize the narrowband vector channel parameters such as spatial signatures, direction-of-arrivals, complex multipath fading, and space-time fading properties in line-of-sight and non-line-of-sight communication links.