Resource allocation for the parallel relay channel with multiple relays

A cooperative network where transmission between two nodes that have no direct link, but assisted by many relays is considered. We assume a broadband system, such as OFDM, modeled by multiple parallel Gaussian subchannels between the source and each relay, and also between each relay and the destination. We formulate the optimization problem for joint power and subchannel allocation under a short term per-node power constraint to maximize the instantaneous total transmission rate between the source and the destination. To solve this optimization problem, first we find the optimal power allocation for a given subchannel allocation. Then we focus on a greedy algorithm that jointly allocates subchannels and power. Simulation results reveal that our proposed algorithm results in rates close to the optimum allocation

Dynamic resource allocation for the broadband relay channel

We consider a half-duplex broadband relay channel which is composed of L parallel, independent Rayleigh fading relay channels. Partial channel state information in the form of channel state amplitudes is available at the transmitters while the receivers have perfect channel state information. We assume a long term total average power constraint at the source and the relay. We dynamically allocate the power and the relay transmission time to improve the delay limited capacity or alternatively to decrease the outage probability. We analyze multi-hop (MH) and opportunistic decodeand-forward (ODF) protocols for the broadband relay channel and propose various subchannel resource allocation strategies. Simulation based performance comparisons also include the modified cut-set bound. \ua9 2007 IEEE