Limited Feedback Transmission Scheme for Wireless Sensor Networks

This paper proposes a limited feedback rate transmission scheme for wireless sensor networks over slowly fading channels. The design approach is based on joint source and channel coding, where source coding characteristics are taken into account to design the transmission protocol for fading channels. The transmission protocol uses an unequal protection regime for different bit groups according to their priority levels while taking into consideration of the variations within and among fading channels. Only group indices are transmitted on the feedback channel from the fusion center to the sensors. This means the feedback channel can operate at a low data rate. Furthermore, it is shown by both theoretical analysis and simulation that the proposed transmission scheme has better performances compared to the distributed beamforming counterpart in low signal-to-noise ratio (SNR) regime.