Achieving Gbps Throughput for Millimeter-Wave WPAN with an Anti-Blocking Scheme Using Deflection Routing

In this paper, we propose a deflection routing scheme for throughput improvement to realize Gbps millimeter-wave wireless personal area network (mmWave WPAN) system. The upcoming mmWave WPAN system is designed to support transmission of uncompressed high definition TV (HDTV), high speed wireless downloading and docking etc. These data-rate-greedy applications require Gbps-order throughput which can be met by the capability of mmWave PHY. However, because of the ad-hoc formed network topology, it is easily happening that the line-of-sight (LOS) path may be blocked, while the non-line-of-sight (NLOS) path is not sufficient to guarantee Gbps throughput due to signal degradation. In this paper, we propose a cross-layer deflection routing (DR) scheme to solve the issue. When the direct path is blocked, the source device finds a relay to form deflection route, send the data to the destination through this alternative route. To avoid throughput degradation due to the consumption of extra time for relay operation, the deflection route is designed to share time slots with other transmissions on direct path. Two routing algorithms are proposed, namely random fit DR (RFDR) and best fit DR (BFDR). They search appropriate relay and time slots that provides sufficient isolation of co-channel interference (CCI) between the transmissions on direct path and deflection route. Computer simulations show that, in realistic 60 GHz environment, Gbps-order system throughput is achieved under blocking condition. There is up to 35% system throughput improvement compared to the conventional relay scheme.