A Novel Node Selection Algorithm for Collaborative Beamforming in Wireless Sensor Networks

Abstract

Collaborative beamforming (CB) provides an effective way of increasing the transmission range and improving the energy efficiency of collaborative sensor nodes in wireless sensor networks (WSNs). Although the mainlobe of the CB beampattern can maintain a stable amplitude, the sidelobes at unintended base stations (BSs) are significantly affected by the randomness of sensor node locations. To reduce the sidelobe power in the direction of unintended BSs, sidelobe control based on node selection needs to be performed. Yet, the computational complexity of optimal node selection is high due to the combinatory nature of the problem. Considering the limited energy supply and computational capabilities of sensor nodes in WSNs, the development low-complexity node selection algorithms is of paramount importance. In this paper, we propose a novel node selection algorithm to control sidelobe at a lower computational complexity. The algorithm consists of two phases which are developed for node selection and node exchange, respectively. The implementation of the proposed algorithm is also presented by detailing its message exchange processes. The performance of the proposed algorithm is evaluated by extensive simulations. Simulation results indicate that the proposed algorithm offers better performance and lower computational complexity in comparison with the existing node selection schemes.