Title :
Adaptive Hierarchical Modulation and Power Allocation of Cooperative Relay
Author :
Wu, Lindong ; Fei, Zesong ; Luo, Chen ; Kuang, Jingming
Author_Institution :
Beijing Inst. of Technol., Beijing, China
Abstract :
In this paper, we consider a Demodulate-and-Forward (DMF) cooperation system, in which a new adaptive hierarchical modulation (HM) and power allocation scheme is proposed. In our new scheme, hierarchical 16-Quadrature Amplitude Modulation (16-QAM HM) is used to offer two different degrees of protection to the transmitted messages and we also employ power allocation between source and relay. A new optimization function based on maximizing the channel capacity, is given to obtain the optimal HM constellation and the best power allocation factor. We assume that all the channel state information (CSI) is available. Simulation results show that the proposed DMF system with our new strategy outperforms the reference system by about 2-2.5 dB.
Keywords :
adaptive modulation; channel capacity; cooperative communication; optimisation; quadrature amplitude modulation; telecommunication security; 16-QAM HM scheme; DMF system; adaptive hierarchical modulation; best power allocation factor; channel capacity; channel state information; cooperative relay; demodulate-and-forward cooperation system; hierarchical 16-quadrature amplitude modulation scheme; optimal HM constellation; optimization function; Bit error rate; Channel capacity; Phase shift keying; Relays; Reliability; Resource management;
Conference_Titel :
Wireless Communications, Networking and Mobile Computing (WiCOM), 2011 7th International Conference on
Conference_Location :
Wuhan
Print_ISBN :
978-1-4244-6250-6
DOI :
10.1109/wicom.2011.6040181
