We consider spatially-coupled protograph-based LDPC codes for the three terminal erasure relay channel. It is observed that BP threshold value, the maximal erasure probability of the channel for which decoding error probability converges to zero, of spatially-coupled codes, in particular spatially-coupled MacKay-Neal code, is close to the theoretical limit for the relay channel. Empirical resul...

In this paper, we investigate the capacity problem of Gaussian fading multiple access relay channel with orthogonal components from the senders to the relay receiver and from the senders and relay to the receiver. This model is motivated by the practical constraint that a node cannot send and receive at the same time or in the same frequency band. We derive a capacity region for the model where...

The authors investigate the performance of amplify-and-forward relaying with two different pilotsymbol-assisted channel estimation methods. In the first estimation method, the cascaded channel consisting of source-to-relay and relay-to-destination links is estimated at the destination terminal. No channel estimator is required at the relay terminal. In the second estimation method, the estimati...

This paper considers the partial decode-and-forward (PDF) strategy for the Gaussian multiple-input multiple-output (MIMO) relay channel. Unlike for the decode-and-forward (DF) strategy or pointto-point (P2P) transmission, for which Gaussian channel inputs are known to be optimal, the input distribution that maximizes the achievable PDF rate for the Gaussian MIMO relay channel has remained unkno...

i−1 1) Fig. 1. Relay channel. The user, aided by the relay, sends the message M to the receiver. The relay channel is a channel in which there is one sender and one receiver with an intermediate node that acts as relay to help the communication. The channel model consists of four finite sets X , X 1 , Y, Y 1 , and a collection of conditional pmfs p(y, y 1 |x, x 1) on X × X 1 × Y × Y 1. The send...

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...

In cooperative relay networks, Channel State Information (CSI) is estimated at receiver. The estimated CSI is sent back to the relays through feedback link. This estimated CSI is often outdated due to feedback delay and the estimated outdated CSI is used for relay selection and detection which affects the performance of the system. The outage and error rate performance of the relay selection sc...

Physical layer security is an attractive security mechanism, which exploits the randomness characteristics of wireless transmission channel to achieve security. However, it is hampered by the limitation of the channel condition that the main channel must be better than the eavesdropper channel. To alleviate the limitation, cooperative communication is introduced. Few studies have investigated t...

In this paper, we study the interference relay-without-delay channel which is an interference channel with a relay helping the communication. We assume the relay’s transmit symbol depends not only on its past received symbols but also on its current received symbol, which is an appropriate model for studying amplify-and-forward type relaying when the overall delay spread is much smaller than th...

This paper studies the transceiver design of the Gaussian two-pair two-way relay channel (TWRC), where two pairs of users exchange information through a common relay in a pairwise manner. Our main contribution is to show that the capacity of the Gaussian two-pair TWRC is achievable to within 1 2 bit for arbitrary channel conditions. In the proof, we develop a hybrid coding scheme involving Gaus...