Energy efficiency of cooperative MISO technique in multi-hop wireless sensor networks

In this paper, the energy efficiency of cooperative multiple-input single-output (MISO) technique for a multi-hop wireless sensor network is investigated and compared with other transmission schemes. Firstly, we present different schemes for data transmission of the cluster farther from base station and calculate their energy consumptions. The results show that the optimal transmission scheme varies with the inter-cluster distance in different networks. Then we explore the lifetime of the network and find that it is not always the optimal to employ the multihop transmission and the single-hop transmission outperform the multi-hop under a certain distance threshold. In addition, the effects of the transmission bit rate and the required bit error ratio (BER) on the distance threshold are also clarified.