We investigate the symmetric degrees of freedom (DoF) of the K-pair (2K users) two-way relay Multiple-Input Multiple-Output (MIMO) Gaussian interference channel for K = 2, 3 where each user is equipped with M antennas and the relay node is equipped with N antennas. The two users of each pair communicate with each other via the help of the relay only. Expressing the DoF characterization as a fun...

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...

We consider a wireless relay network, where a transmitter node communicates with a receiver node with the help of relay nodes. Most coding strategies considered so far assume that the relay nodes are used for one hop. We address the problem of code design when relay nodes may be used for more than one hop. We consider as a protocol a more elaborated version of amplify-andforward, called distrib...

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...

—This paper considers a two-way relay network (TWRN) with two sources and one relay node, where each source is equipped with a single antenna, while the relay node is equipped with a large number of antennas. We propose two low-complexity physical-layer differential network coding schemes for such TWRNs, namely, Superimposition Coding based Differential Beamforming (SC-DBF) and Decode-andForwa...

In spectrum sharing systems, a secondary user (SU) is permitted to share frequency bands with primary user (PU) as long as its transmission does not interfere with the PU’s communication. In this paper, the outage probability is investigated for the physical-layer network coding (PNC) based cognitive two-way relay network over Nakagami-m fading channel. By applying the interference temperature ...

The issue of resource allocation for MSE minimization in a DS/CDMA amplify-and-forward relayassisted interference channel is addressed in this paper. The resource allocation process is assumed to take place in a hierarchical way. First, the relay announces his amplifyand-forward matrix, and then the multiple access users non-cooperatively react to the relay’s choice. This process is modeled by ...

Energy efficient transmission has become increasingly important in future green communications. We focus on cooperative networks with multiple Amplify-and-Forward relays deployed in this paper. A joint relay selection and power allocation transmission scheme applicable to both one-way and two-way relay networks is proposed for minimizing the weighted energy consumed per bit transmitted. Close-f...