Results 221 to 230 of about 12,621 (257)

On the Spectral Efficiency of Selective Decode-and-Forward Relaying

IEEE Transactions on Vehicular Technology, 2016
Multirelay cooperative relaying enables spatial diversity, often at the expense of spectral efficiency. To alleviate the loss in spectral efficiency due to half-duplex relaying and transmission over orthogonal channels, we propose a novel transmission scheme for selective decode-and-forward (DF) networks.
Hamza Umit Sokun, Halim Yanikomeroglu
openaire   +1 more source

Compressive cooperative communication with decode and forward relay

2016 8th International Conference on Communication Systems and Networks (COMSNETS), 2016
The theory of compressive sensing (CS) is acquiring attraction now a days, as it can reconstruct a sparse signal at a sub-Nyquist sampling rate. Recently CS is being used in communication systems for channel estimation, Massive MIMO, cognitive radio etc. In this paper, CS is using in an overlay cooperative spectrum sharing scheme for decode and forward
Neha Jain 0002, Vivek Ashok Bohara, Anubha Gupta   +2 more
openaire   +1 more source

Adaptive Modulation for Opportunistic Decode-and-Forward Relaying

IEEE Transactions on Wireless Communications, 2011
Orthogonal relay based cooperative communication enjoys distributed spatial diversity gain at the price of spectral efficiency. This work aims at improving the spectral efficiency for orthogonal opportunistic decode-and-forward (DF) relaying through employment of novel adaptive modulation scheme.
Yi Ma 0002, Rahim Tafazolli, Yuanyuan Zhang 0004, Chuyi Qian   +3 more
openaire   +3 more sources

Bit-wise combining for decode-and-forward relays

2012 IEEE Wireless Communications and Networking Conference Workshops (WCNCW), 2012
We consider the problem of combining the signals received from a decode-and-forward relay with those received from the source. As an alternative to the high-complexity maximum-likelihood combining strategy, we propose a bit-wise combining strategy in which the received signals are first converted to log-likelihood values before being combined.
Namshik Kim, John R. Barry
openaire   +1 more source

Decode-and-forward relaying technique in UMTS networks

2010 7th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP 2010), 2010
As fading due to multipath propagation is an important issue in wireless systems, diversity techniques are employed in order to reduce the multipath fading effect. Cooperative communication represents a new class of diversity schemes in which multiple nodes equipped with a single antenna cooperate to generate a virtual multiple-antenna transmission ...
Mingkwan Somphruek, Rolando A. Carrasco, Stéphane Y. Le Goff   +2 more
openaire   +1 more source

Dynamic Selective Decode and Forward in wireless relay networks

2015 7th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT), 2015
In this paper, we propose a practical code design for a new relaying protocol, coined Dynamic Selective Decode-and-Forward (D-SDF), in half-duplex slow fading Multiple Access Multiple Relay Channel (MAMRC), defined as follows: (1) Multiple statistically independent sources communicate with a single destination with the help of multiple half-duplex ...
Abdulaziz Mohamad, Raphaël Visoz, Antoine O. Berthet   +2 more
openaire   +1 more source

Enhanced MRC for Decode-and-Forward Cooperative Diversity Systems

IEEE Transactions on Wireless Communications, 2012
In this letter, we propose a novel enhanced maximal-ratio combining (E-MRC) scheme for multi-branch decode-and-forward (DF) cooperative diversity systems consisting of a source, a destination, and multiple relays. This scheme employs adjustable parameters at the relays and the destination which enable this scheme to appropriately adapt to variations in
Amir Nasri, Robert Schober, Murat Uysal
openaire   +2 more sources

Performance Evaluation of Decode-and-Forward Satellite Relaying

IEEE Transactions on Vehicular Technology, 2015
In this paper, we consider decode-and-forward (DF) relaying of the data of a multiple-antenna-based source Earth station, via a single-antenna-based satellite, to a multiple-antenna-based destination Earth station. The source uses beamforming for transmission of the data, and the destination utilizes the maximal ratio combining for demodulating the ...
openaire   +1 more source

Bilayer LDPC Convolutional Codes for Decode-and-Forward Relaying

IEEE Transactions on Communications, 2013
In this paper we present bilayer LDPC convolutional codes for half-duplex relay channels. Two types of codes, bilayer expurgated LDPC convolutional codes and bilayer lengthened LDPC convolutional codes, are proposed for decode-and-forward (DF) relaying.
Si Z., Thobaben R., Skoglund M.
openaire   +2 more sources

Error bounds for decode-and-forward relaying

2010 European Wireless Conference (EW), 2010
We analyze and compare the maximum-likelihood (ML) decoder and the maximum a-posteriori (MAP) decoder for coding over a decode-and-forward relay network with orthogonal channels. Using a specific model for the errors introduced by the relay, we derive an optimal MAP decoder that operates on a super-trellis and estimates jointly the transmitted codeword
Graell I Amat, Alexandre, Land, Ingmar, Rasmussen, Lars K.   +2 more
openaire   +2 more sources