Enhancing In-Home 802.11 Performance: Mesh or MIMO?

This paper analyses the throughput and coverage of an in-home wireless LAN in the 5GHz band. A novel approach is proposed based on part measurement, part simulation. The spatial and temporal characteristics of typical in-home channels are modelled using 3D ray tracing and combined with measured and appropriately orientated complex polarmetric patterns for each antenna element. Physical layer throughput is computed across 10 rooms in a virtual test house for all modulation and coding schemes. To accelerate the simulation process a received bit information rate abstraction technique is applied. Results are given for a standard 802.11a deployment. The benefits of 3x3 MIMO are then compared against the deployment of a Wireless Mesh Network (WMN). In the latter case meshing is performed using low cost single antenna radios. Relative to the benchmark SISO system, 3x3 MIMO is shown to improve the average throughput by 123%. Given four randomly deployed mesh points, the mesh solution improves the average throughput by 31%. Importantly, for the test house under consideration the MIMO solution improves connectivity by just 3%, while the mesh network offers 100% (whole home) connectivity. The mesh network (using 4 additional mesh points) is shown to support high definition video for 90% of the links, compared to 71% with 3x3 MIMO. Results confirm that mesh networks benefit the weaker links, while MIMO boosts the stronger links.