Results 241 to 250 of about 139,289 (280)

Robust Power Allocation for Amplify-and-Forward Relay Networks

2007 IEEE International Conference on Communications, 2007
Relay power allocation has been shown to provide substantial performance gain in wireless relay networks when perfect global channel state information (CSI) is available. In this paper, we consider a more realistic scenario, where such global CSI is subject to uncertainty, and we aim to design robust power allocation protocols for both the coherent and
T. Q. S. Quek, H. Shin, M. Z. Win, CHIANI, MARCO   +3 more
openaire   +2 more sources

Amplify-and-forward with full-duplex relay selection

2012 IEEE International Conference on Communications (ICC), 2012
This paper focuses on the relay selection problem in amplify-and-forward (AF) cooperative communication with full-duplex (FD) operation. Different relay selection schemes assuming the availability of different instantaneous information are studied. We consider an optimal relay selection that maximizes the instantaneous FD channel capacity and requires ...
Krikidis, Ioannis A., Suraweera, H. A., Yuen, C., Krikidis, Ioannis A., Suraweera, H. A., Yuen, C.   +5 more
openaire   +2 more sources

Beamforming in Nonorthogonal Amplify-and-Forward Relay Networks

IEEE Transactions on Vehicular Technology, 2011
This paper considers wireless amplify-and-forward (AF) relay networks in which the source communicates with the relays and destination in the first phase and the relays simultaneously forward signals to the destination in the second phase over uncorrelated Rayleigh fading channels.
Tung T. Pham, Ha H. Nguyen, Hoang D. Tuan   +2 more
openaire   +1 more source

Multistage cooperative broadcast using amplify-and-forward relays

2010 - MILCOM 2010 MILITARY COMMUNICATIONS CONFERENCE, 2010
In this work we study the propagation of the signal in a cooperative network where a single source message is retransmitted by multiple stages (levels) of relays. Relays are assumed to have limited computational abilities and hence adopt the amplify-and-forward scheme.
Bhargava Yammanuru, Birsen Sirkeci-Mergen   +1 more
openaire   +1 more source

Cooperative Amplify-and-Forward with Trellis Coded Modulation

2009 IEEE Wireless Communications and Networking Conference, 2009
In a cooperative communication network, individual users are encouraged not only to transmit their own data, but also relay other user's data. This relaying transmission creates spatial diversity to combat the effect of individual severe fading and path loss.
L. Chen, R. A. Carrasco, S. LeGoff, I. J. Wassell   +3 more
openaire   +1 more source

Distributed Amplify-and-Forward with Ring-TCM Codes

2010 7th IEEE Consumer Communications and Networking Conference, 2010
This paper proposes a new distributed Amplify-and-Forward (AF) scheme which is integrated with the Ring-Trellis Coded Modulation (TCM) codes in order to achieve both high spectral efficiency and large diversity gain. In the distributed AF scheme, more users cooperate with each other.
Li Chen, Rolando Carrasco, Ian Wassell
openaire   +1 more source

Average approach to amplify-and-forward relay networks

2009 9th International Symposium on Communications and Information Technology, 2009
In this paper, the analysis of an average received signal-to-noise ratio (SNR) for a cooperative communication network with amplify-and-forward (AF) relays is presented. In AF systems, the overall instantaneous SNR at the receiving end can be expressed as the form of a harmonic mean of perhop SNRs.
Won-Chul Choi, Seokkwon Kim, Seung-Ri Jin, Dong-Jo Park   +3 more
openaire   +1 more source

Two-Way Full-Duplex Amplify-and-Forward Relaying

MILCOM 2013 - 2013 IEEE Military Communications Conference, 2013
Full-duplex transmission is a promising technique to enhance the capacity of communication systems. In this paper, we investigate two-way amplify-and-forward (AF) relay systems in the full-duplex scenario. Compared with the traditional half-duplex AF relaying, the full-duplex system uses only a single phase to complete the two-way or bidirectional ...
Xilin Cheng, Bo Yu, Xiang Cheng, Liuqing Yang   +3 more
openaire   +1 more source

On Slotted Amplify-and-Forward Cooperative Diversity Schemes

2006 IEEE International Symposium on Information Theory, 2006
All previously proposed amplify-and-forward (AF) and decode-and-forward (DF) schemes do not improve with the number of relays in terms of the diversity-multiplexing tradeoff (DMT) for multiplexing gains r higher than 0.5. In this work, we study the class of slotted amplify-and-forward (SAF) schemes.
Sheng Yang, Jean-claude Belfiore
openaire   +1 more source

Outage optimality of opportunistic amplify-and-forward relaying

IEEE Communications Letters, 2007
In this paper, we show that optimal selection and transmission of a single relay among a set of multiple amplify-and-forward (AF) candidates minimize the outage probability (i.e., outage-optimal) and outperform any other strategy that involves simultaneous transmissions from more than one AF relay under an aggregate power constraint.
A. Bletsas, H. Shin, M.Z. Win
openaire   +1 more source