Performance analysis of an amplify-based differential modulation for wireless relay networks under Nakagami-m fading channels

This paper examines differential binary modulation for wireless networks that utilize wireless relays to seek cooperative diversity and improved performance over Nakagami-m fading channels. A differential cooperative transmission scheme, referred to as differential amplify-and-forward (DAF), is introduced. The scheme requires no channel state information (CSI) at any node in the system. A differential detection is discussed. A set of analytical results pertaining to the probability density function (PDF) of the instantaneous signal-to-noise ratio (SNR) and average bit error rate (BER) are obtained. The analytical results are confirmed by numerical simulations. It is instrumental to apply the derived closed-from BER expression to evaluate system performance under Nakagami-m fading channels.