Energy-aware virtual multi-input-multi-output-based routing for wireless ad hoc networks

Virtual multi-input-multi-output (vMIMO) technology is becoming a promising way to improve the energy efficiency of wireless networks. Previous research always builds up the vMIMO-based routing on the fixed structure such as clusters, and the MIMO mode is omitted in most cases. So, they cannot fully explore the advantage of vMIMO in routing. In this paper, we study a general routing scheme in which no fixed structure is required, and any communication mode of vMIMO is allowed for sake of the energy efficiency. We define two vMIMO-based routing problems aiming to energy-minimization and lifetime-optimization. The first problem can be solved by our distributed energy-minimum vMIMO-based algorithm. The algorithm constructs the virtual cooperative graph, and applies the shortest path method on the virtual cooperative graph to solve this problem. The second problem is non-deterministic polynomial-time hard, and we design the distributed lifetime-oriented vMIMO-based algorithm, which is based on the modified Bellman-Ford method. It can reach approximation ratio of four. The simulations show that our algorithms can work well in many situations. For example, distributed lifetime-oriented vMIMO-based algorithm can prolong the lifetime about 20.2% in dense topologies compared with the cooperative routing algorithm on average. Copyright (c) 2015 John Wiley & Sons, Ltd.