Performance analysis and optimal power allocation for the incremental quadrature modulation cooperative system
Ma Bo · Journal of Xidian University · 2012
In order to improve the reliability of the quadrature modulated(QM) cooperative diversity system,an incremental quadrature modulated(IQM) cooperative diversity system and its power allocation schemes are proposed,by introducing incremental relaying.Firstly,the system's Markov states-transform probability is obtained through the analysis of the system's Markov-process and then the closed approximate solution of the frame error rate(FER) is acquired.Finally,a quasi-optimized power allocation schemes(QOPA) with low complexity is presented.By minimizing the frame error rate(FER),the optimal power factors are obtained through iterative computation.Simulation result shows that the IQM system outperforms the traditional QM system by a maximum SNR benefit of 4 dB when the FER is in the range [10-4,10-2].Moreover,an additional 3 dB performance gain is obtained by adopting the QOPA schemes.