Multipath routing with spatial separation in wireless multi-hop networks without location information

We develop an on-demand multipath routing protocol for multi-hop wireless networks (MWNs), capable of finding spatially disjoint paths (paths physically distant from each other) without the need of location information. Multipath routing can enable various applications and enhancements in MWNs, such as load balancing, bandwidth aggregation, reliability and secure communications. The use of spatially disjoint routes is important to effectively achieve these gains, due to the non-interfering nature and distance of the paths. Most of the proposed multipath protocols for MWNs focus on reliability and do not find spatially separate paths. We propose a new on-demand protocol called Spatially Disjoint Multipath Routing (SDMR), capable of finding multiple paths in one route discovery, measuring the distance between them and choosing paths with most separation. A new distance metric is presented to measure path separation, which proves to be congruent with Euclidean distance across nodes in the paths. We develop a heuristic algorithm which, given a topology graph and utilizing the proposed distance metric, can discover spatially disjoint paths between any two nodes in the graph. To evaluate the protocol, we have studied the overhead both analytically in comparison with OLSR, and by simulation. The simulations also demonstrate the effectiveness of the protocol in finding spatially separate routes.