Improving amplify-and-forward relay networks: optimal power allocation versus selection

We consider an amplify-and-forward (AF) cooperative diversity system where a source communicates with a destination with the help of multiple relay nodes. The conventional system assumes all relay nodes participate, with the available channel and power resources equally distributed over all nodes. This approach being clearly sub-optimal, we first present an optimal power allocation scheme to minimize the outage probability for an AF system. Next, we propose a new selection scheme where only one, the "best" relay node is chosen to participate in the transmission. We show that at reasonable power levels the selection AF scheme maintains full diversity order, and has significantly better outage behavior and average throughput than the conventional scheme or that with optimal power allocation

[1]  David G. Luenberger,et al.  Linear and nonlinear programming , 1984 .

[2]  Gregory W. Wornell,et al.  Distributed space-time-coded protocols for exploiting cooperative diversity in wireless networks , 2003, IEEE Trans. Inf. Theory.

[3]  Alexander M. Haimovich,et al.  Power allocation for cooperative relaying in wireless networks , 2005, IEEE Communications Letters.

[4]  Alejandro Ribeiro,et al.  Symbol error probabilities for general Cooperative links , 2005, IEEE Trans. Wirel. Commun..

[5]  Georgios B. Giannakis,et al.  On energy efficiency and optimum resource allocation of relay transmissions in the low-power regime , 2005, IEEE Transactions on Wireless Communications.

[6]  Lizhong Zheng,et al.  Diversity and multiplexing: a fundamental tradeoff in multiple-antenna channels , 2003, IEEE Trans. Inf. Theory.

[7]  D.R. Brown,et al.  Resource allocation for cooperative transmission in wireless networks with orthogonal users , 2004, Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004..

[8]  Yingbin Liang,et al.  Resource allocation for wireless relay channels , 2004, Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004..

[9]  David G. Luenberger,et al.  Linear and Nonlinear Programming: Second Edition , 2003 .

[10]  Aggelos Bletsas,et al.  A simple Cooperative diversity method based on network path selection , 2005, IEEE Journal on Selected Areas in Communications.

[11]  R. Adve,et al.  On Selection Cooperation in Distributed Networks , 2006, 2006 40th Annual Conference on Information Sciences and Systems.

[12]  A. Bletsas,et al.  A simple distributed method for relay selection in cooperative diversity wireless networks, based on reciprocity and channel measurements , 2005, 2005 IEEE 61st Vehicular Technology Conference.

[13]  Helmut Bölcskei,et al.  Fading relay channels: performance limits and space-time signal design , 2004, IEEE Journal on Selected Areas in Communications.

[14]  Thomas M. Cover,et al.  Elements of Information Theory , 2005 .

[15]  Gregory W. Wornell,et al.  Cooperative diversity in wireless networks: Efficient protocols and outage behavior , 2004, IEEE Transactions on Information Theory.

[16]  Armin Wittneben,et al.  Impact of relay gain allocation on the performance of cooperative diversity networks , 2004, IEEE 60th Vehicular Technology Conference, 2004. VTC2004-Fall. 2004.

[17]  Hesham El Gamal,et al.  Distributed space-time filtering for cooperative wireless networks , 2003, GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489).

[18]  Junshan Zhang,et al.  Capacity Bounds and Power Allocation for the Wireless Relay Channel , 1990 .

[19]  Georgios B. Giannakis,et al.  On Energy Efficiency and Optimum Resource Allocation of Relay Transmissions , 2003 .

[20]  Anders Høst-Madsen,et al.  Capacity bounds and power allocation for wireless relay channels , 2005, IEEE Transactions on Information Theory.

[21]  Mazen O. Hasna,et al.  Optimal power allocation for relayed transmissions over Rayleigh-fading channels , 2004, IEEE Transactions on Wireless Communications.