Relay channel was firs introduced by van der Meulen [1, 2, 3]. Time sharing approaches were used to find inner bounds for the capacity. Most of the known results stem from the publication [4] by Dr. Thomas M. Cover and Dr. Abbas A. El Gammal. In this paper, capacity of degraded relay channels, relay channels with feedback is computed. Also lower bounds using Block Markov coding (decode and forw...

A discrete memoryless half-duplex relay channel is constructed from a broadcast channel from the source to the relay and destination and a multiple access channel from the source and relay to the destination. When the relay listens, the channel operates in the broadcast mode. The channel switches to the multiple access mode when the relay transmits. If the broadcast component channel is physica...

The problem of jointly optimizing the source precoder, relay transceiver, and destination equalizer has been considered in this paper for a multiple-input-multiple-output (MIMO) amplify-and-forward (AF) relay channel, where the channel estimates of all links are assumed to be imperfect. The considered joint optimization problem is nonconvex and does not offer closed-form solutions. However, it ...

In view of the low efficiency and poor coding performance, an active mechanism network coding algorithm based on multi-channel sensing is proposed. The algorithm first establishes a system model to analyze the work pattern of network coding, then selects the minimum sample as cost function and adopts the multi-channel sensing to examine the coding effect of relay node, which makes the network t...

In this paper, we investigate the individual channel estimation over the three-node one-way relay network (OWRN), where all nodes are equipped with multiple antennas. We first examine the scenario where the relay node is equipped with single antenna. An iterative linear minimum mean-square-error (LMMSE) method, which has fast convergence speed, is proposed to estimate the individual channels. T...

Cooperative diversity can be achieved by a relay node (R) assisting in a transmission between a source (S) and a destination (D). However, in general, the proposed cooperation schemes ignore the quality of the S-R channel in the decoding process. This paper introduces a novel and robust scheme for cooperative diversity that accounts for the quality of the S-R channel. In our scheme, the relayin...

In this paper, a cooperative algorithm to improve the orthogonal space-timefrequency block codes (OSTFBC) in frequency selective channels for 2*1, 2*2, 4*1, 4*2 MIMO-OFDM systems, is presented. The algorithm of three node, a source node, a relay node and a destination node is formed, and is implemented in two stages. During the first stage, the destination and the relay antennas receive the sym...

The prominence of the wireless communication has been urging the monotonically increasing demand of security and privacy. In wireless systems, the notion of perfect secrecy of information with respect to illegitimate nodes can be ensured via physical layer security (PLS) techniques. Unfortunately, they can be made less effective if sourceeavesdropper wiretap channel is better than the main sour...