Routing and handoff support for a novel wireless broadband access network (UniNet)

UniNet is a new type of wireless access network for offering broadband mobile and stationary services to homes, offices, pedestrians, and vehicles. The basic architecture involves high capacity radio pico-cells interconnected via short, highly focused free-space optical or microwave links in a multihop mesh arrangement, with traffic relayed by the mesh to the end office. We present an integrated approach for addressing routing and hand-off. Based on the minimum spanning tree and other heuristics, multiple virtual connection trees are progressively constructed and shared by all traffic; the system simply chooses the least-loaded tree for each new connection. Our approach can avoid congestion and evenly distribute traffic in the mesh, even when the traffic distribution is non-uniform and mobility is introduced. The performance is close to ideal and frequent hand-off easily can be tolerated. Trees can be pre-defined and the process of selecting trees to accommodate new calls is quite simple.