Cooperative Spatial Reuse with Transmit Beamforming

A cooperative scheme enabling spatial reuse, namely cooperative spatial reuse (CSR), is proposed as a cooperative extension of the current TDMA-based MAC in wireless networks. In the CSR, a cooperative group is formed by the links that are willing to do spatial reuse. In the group, every cooperating link contributes its time slots for spatial reuse among the cooperating participants. Following the cooperation principle, a link joins the group only if it can benefit. Otherwise, the link will stop doing CSR and switch back to the TDMA-based MAC. In this work, we focus on the transmit beamforming techniques to enable CSR on MISO (Multiple Input Single Output) links. We compared the CSR scheme using zero-forcing (ZF) transmit beamforming, namely ZF-CSR, to the TDMA-based MAC using maximum ratio combining (MRC) transmit beamforming, namely MRC-TDMA. The numerical results of a simulated two 2 x 1 MISO links scenario show the great potential of CSR to substantially increase the capacity and energy efficiency.