This letter introduces a joint design method for uplinkdownlink multiple-input multiple-output (MIMO) relay communication systems in which the source nodes transmit information to the destination nodes with the help of a relay. We propose a signal forwarding schceme based on the minimum mean-square error (MMSE) approach in uplink relay systems. Exploiting the duality of relay systems, we also p...

This paper investigates rate adaptation schemes for decoding-and-forward (DF) relay system based on random projections codes (RPC). We consider a classic three node relay system model, where relay node performs on half-duplex mode. Then, we give out receiving diversity relay scheme and coding diversity relay scheme, and present their jointly decoding methods. Furthermore, we discuss the perform...

Relay based cooperative spectrum sensing elevates the spectrum sensing problems in harsh propagation conditions if the relay nodes are positioned suitably for the dynamic spectrum access systems. This article investigates the performance of relay based spectrum sensing (energy detection based) in myriad fading environments using the area under the receiver operating characteristic curve (AUC) p...

In this paper, we consider two-way orthogonal frequency division multiplexing (OFDM) relay channels, where the direct link between the two terminal nodes is too weak to be used for data transmission. The widely known per-subcarrier decode-and-forward (DF) relay strategy, treats each subcarrier as a separate channel, and performs independent channel coding over each subcarrier. We show that this...

This paper presents a new cooperative ARQ protocol for a hybrid mobile wireless sensor network. The mobile relay nodes decode the signal from the source sensor using cyclic redundancy check (CRC) and forward it to the destination sink. A distributed relay selection that exploits overhearing of inter-relay node transmission is employed to achieve higher selection diversity gain during retransmis...

© 2010 ETRI Journal, Volume 32, Number 2, April 2010 The IEEE802.16j standard uses non-transparent relay stations to extend coverage. There are two types of nontransparent relay modes, that is, the time-division transmit and receive (TTR) relay mode which can operate with one of two types of frame structures, a single-frame and multiframe structure, and the simultaneous transmit and receive (ST...

Relay networks have recently attracted extensive attention due to its potential to increase coverage area and channel capacity. In a relay network, a source node communicates with a destination node with the help of the relay node. The performances of improving the channel capacity and coverage area have been explored and evaluated in the literature (Sendonaris et al., 2003)-(Laneman et al., 20...