This article considers uniand bidirectional communication in the half-duplex Gaussian multiple-input multiple-output (MIMO) relay channel. Assuming perfect channel state information at all nodes and the use of time division duplex communications protocol to separate transmissions and receptions at all nodes, we propose a dual decomposition approach to efficiently determine upper and lower bound...

With the fast development of communication networks, cooperative communication has been more widely used in many different fields, such as satellite networks, broadcast networks, internet and so on. Therefore relay channels have been playing a pivotal role since their definitions were proposed by Van-der Meulen. However, the general achievable rate region of a relay channel is still unknown whi...

Optimal precoding in the relay is investigated to maximize ergodic capacity of a multiple antenna relay channel. The source and the relay nodes are equipped with multiple antennas and the destination with a single antenna. It is assumed that the channel covariance matrices of the relay’s receive and transmit channels are available to the relay, and optimal precoding at the relay is investigated...

This paper studies the problem of detecting a potential malicious relay node by a source node that relies on the relay to forward information to other nodes. The channel model of two source nodes simultaneously sending symbols to a relay is considered. The relay is contracted to forward the symbols that it receives back to the sources in the amplify-and-forward manner. However there is a chance...

In this paper, we derive a new achievable rate region for the user cooperation channel, which exceeds the best known result for this channel [Wil83]. Since the user cooperation channel includes many other known channels as a special case, the new rate region provides an improved achievable rates for many of the special cases (discussed later). The most notable example is that of the Gaussian re...

The Multiple-access Relay Channel (MARC) has been considered as a promising technique in next generation wireless communication networks. In this work, we study a Network Coding based Multiaccess Relay Channel (NC-MARC) where a decode-and-forward relaying and a static XOR network coding are considered for the one-way relaying system. The system consists of two transmitters communicating with a ...

Relaying (1–3) has been considered as a paradigm for improving the quality of service (i.e., bit-error-rate, data rate and coverage) in wireless networks. In this work, we study a two-hop relay channel in which each node can have multiple antennas. It is well-known that utilizing multiple-input multiple-output (MIMO) links can significantly improve the transmission rate (see e.g. (4; 5) and ref...

In this paper, we derive a capacity region for Gaussian fading multiple access degraded relay channel with partial channel state information (CSI) at the transmitters (CSIT) and perfect CSI at the receiver (CSIR). The achievable rate region obtained by Kramer-Wijngaarden is a special case of our region. Keywords-Gaussian fading channel; channel state information (CSI); discrete multiple access ...

An achievable rate for the discrete memoryless relay channel with receiver-transmitter feedback is proposed based on Block-Markov superposition encoding. The achievable rate can also be extended to Gaussian channels. A second achievable rate for the Gaussian relay channel based on a Schalkwijk-Kailath type scheme is presented. For some channels both achievable rates strictly improve upon all pr...

This paper investigates the degrees of freedom (DoF) of the L-cluster, K-user MIMO multi-way relay channel, where users in each cluster wish to exchange messages within the cluster, and they can only communicate through the relay. A novel DoF upper bound is derived by providing users with carefully designed genie information. Achievable DoF is identified using signal space alignment and multipl...