In this paper, we model a specific relay channel named relay multiple access channel (RMAC) aiming at providing a clue to select the relay node in multiple access channels such as the uplink of cellular communication system. In this channel, the relay node not only aids to send the information of the source but also sends its private message to the destination. We derive the achievable rate reg...

The interference channel with a cognitive relay consists of a classical interference channel with two sourcedestination pairs and with an additional cognitive relay that has a priori knowledge of the sources’ messages and aids in the sources’ transmission. We derive a new outer bound for this channel using an argument originally devised for the “more capable” broadcast channel, and show the ach...

Relay selection is an attractive method to improve the bandwidth efficiency of cooperative networks [1]-[3]. Specifically, Bletsas and others [1] proposed a distributed relay selection based on the channel information of both the first and second hops for each relay, showing that the diversitymultiplexing tradeoff of relay selection is identical with that of distributed space-time coding. Recen...

This paper analyzed the performance of multihop relay cooperative spectrum sensing. The closed form expression of the upper bound of the detection probability of multi-hop relay cooperation is derived in Rayleigh flat fading channel. It provides the theoretical basis for analyzing the performance of multi-hop relay cooperative spectrum sensing. Simulation results show that the detection probabi...

In this study, two hop non-regenerative Multiple Input Multiple Output (MIMO) relay network is considered. Each node of the network is equipped with multiple antennas. We apply an efficient linear processing at the relay node only. We utilize Minimum Mean Square Error (MMSE) as the relay receive beamforming and PerAntenna-Signal to Leakage plus Noise Ratio (PA-SLNR) maximization criteria using ...

We present capacity bounds and achievable rates of the Gaussian relay channel. To evaluate achievable rates we consider two cooperative strategies: decode and forward (DF) and compress and forward (CF). We investigate the impact of different channel conditions of the transmitter-relay, relay-receiver, and transmitter-receiver transmission on the bounds and rates. We also compare the results to ...

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In 1987, Cover proposed an interesting problem in the simple relay channel [1] as shown in figure 1. In this channel, pp(yy11,yy22|xx) = pp(yy11|xx)pp(yy11|xx) and the channel from YY11 to YY22 does not interfere with YY22. Denote the rate from YY11 to YY22 as CC00. The critical value of CC00 such that CC(CC00) first equals CC(∞) is determined in this paper. In order to achieve this, a new deco...