Cooperative MIMO Systems in Wireless Sensor Networks
M. Riduan, Eryk Dutkiewicz, Xiaojing Huang, M. Kadim · InTech eBooks · 2010
This chapter has examined the major diversity techniques and various cooperative configurations, including BF, STBC and SM schemes in conjunction with performance evaluation and comparative literature. Both cooperative BF and STBC schemes utilise the MISO concept while the SM scheme utilises the MIMO concept. We have shown that the cooperative MISO BF is the most promising scheme to be implemented in WSNs due to the lowest error performance among others with the same diversity gain. Also, cooperative MISO BF outperforms other cooperative schemes in imperfect synchronisation scenarios. On the other hand, cooperative MIMO SM is more practical in terms of lower error performance and tolerance to clock jitter error when its diversity gain is higher than the others. In addition, cooperative MIMO SM provides a higher spatial rate as M grows. The comparative study relates the diversity gain with the reduction in the transmission power by increasing the communication link reliability. However, in order to find the best or optimal scheme to be used in WSNs, we have to compare all the three schemes in terms of total energy consumption which must include both the transmission power and circuit power for each sensor node in the network. The discussion in this chapter can provide a basis for further study to find the optimal cooperative MIMO scheme when both transmission power and circuit power are considered for all required energy components of cooperative communications in WSNs.