Results 231 to 240 of about 139,289 (280)

Adaptive Amplify-and-Forward Relaying for Cellular Downlink

IEICE Transactions on Communications, 2011
This paper presents an adaptive amplify-and-forward (AF)-type relaying method appropriate for the cellular downlink. The proposed method adaptively selects active relay stations (RSs) based on the path loss between each set of user equipment (UE) and the base station (BS) and that between each RS in order to avoid unnecessary enhancement of inter-cell ...
Kiichi Tateishi, Kenichi Higuchi
openaire   +1 more source

Lifetime Maximization for Amplify-and-Forward Cooperative Networks

2007 IEEE Wireless Communications and Networking Conference, 2007
Joint relay-selection and power-allocation strategies are devised to prolong the lifetime of amplify-and-forward (AF) cooperative networks. Lifetime is defined as the time duration within which the desired signal-to-noise ratio (SNR) at the destination is met with a certain probability. Based on selective relaying, we propose three strategies that take
null Wan-Jen Huang, Y.-W.P. Hong, C.-C.J. Kuo   +2 more
openaire   +1 more source

Cooperative Phase Sweep Amplify-and-Forward Transmission

2008 IEEE 68th Vehicular Technology Conference, 2008
This work presents a new amplify-and-forward (AF) cooperative multiple input multiple output (MIMO) transmission scheme based on phase sweep transmit diversity. In a single hop cooperative link, the relay node imposes a phase sweep on the signal it receives from the source node.
Geoffrey G. Messier, Sebastian Magierowski, Jean-Francois Bousquet   +2 more
openaire   +1 more source

An amplify-and-forward scheme for cognitive radios

2014 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2014
In this paper, we propose an opportunistic amplify-and-forward relaying scheme for a cognitive radio network, which is aimed at allowing a secondary user (SU) to transmit over the same timefrequency slot of a primary user (PU). In our scheme, the SU amplifies and transmits the PU signal it receives, by using as relaying gain the information symbols ...
VERDE, FRANCESCO, Anna Scaglione, GELLI, GIACINTO, Donatella Darsena   +3 more
openaire   +3 more sources

Performance of Untrusted Amplify-and-Forward Relaying

2013 4th International Conference on Intelligent Systems, Modelling and Simulation, 2013
In this paper, we analyze the secrecy outage performance of amplify-and-forward (AF)-based relay networks consisting of a source, a destination, and an untrusted relay, where each terminal has a single antenna and operates in a half-duplex mode. In this network, the common message is transmitted through the relay-path, and the private message is ...
null MinChul Ju, null Do-Hoon Kim
openaire   +1 more source

Relay-Aided Amplify-and-Forward Powerline Communications

IEEE Transactions on Smart Grid, 2013
Powerline communications (PLC) is a favorable technique for many smart grid applications. By transmitting information over the existing powerline infrastructure, PLC has the benefit of low deployment cost. However, due to low transmit power, limited bandwidth, and harsh channel conditions, reliable long-distance and high-capacity PLC is challenging ...
Xilin Cheng, Rui Cao, Liuqing Yang
openaire   +1 more source

An Amplify-and-Forward architecture for low spectral efficiencies

2009 IEEE International Symposium on Circuits and Systems, 2009
This paper proposes a simple architecture for half-duplex cooperative systems which use Amplify-and-Forward (AF) as a relay strategy and one-dimensional modulations for source messages. The proposed solution uses the two orthogonal channels of quadrature modulation in order to allow a node to behave simultaneously as a source and a relay. We prove that
Krikidis, Ioannis A., Krikidis, Ioannis A.   +1 more
openaire   +2 more sources

Non-orthogonal Amplify-and-Forward for block-fading channels

2008 IEEE International Symposium on Information Theory, 2008
In this paper, we deal with the amplify-and-forward (AF) cooperative strategy in slot-based block-fading environments. In contrast with previous schemes which assume a constant channel during the cooperative frame (several slots), here, we relax this constraint and assume a classical quasi-static block-fading channel (constant for one slot).
Krikidis, Ioannis A., Thompson, J., McLaughlin, S., Goertz, N., Krikidis, Ioannis A., Thompson, J., McLaughlin, S., Goertz, N.   +7 more
openaire   +2 more sources

Overview of Amplify-and-Forward Relaying

2010
Amplify-and-Forward (AF) is a simple cooperative strategy for ad-hoc networks with critical power constraints. It involves an amplification of the received signal in the analogue domain at the relays without further signal processing. This chapter gives an overview of the basic AF protocols in the literature and discuss recent research contributions in
Ioannis Krikidis, John S. Thompson
openaire   +1 more source

Flexible Amplify and Forward Relaying Protocol with Optimized Duplexing

VTC Spring 2009 - IEEE 69th Vehicular Technology Conference, 2009
In this paper we propose a novel flexible amplify and forward (AF) relaying protocol with different duplexing ratios. We show that the average throughput can be considerably improved by properly adjusting the duplex ratio. Here it is considered that the transmitted and received channel state information (CSI) are available at the relay.
Fazel M.S., Hoshyar R., Tafazolli R.
openaire   +1 more source