Joint Power Allocation Method Research Articles

Joint Power Allocation for NOMA-Based Diamond Relay Networks With and Without Cooperation

Non-orthogonal multiple access (NOMA)-based diamond relaying (NDR) is an efficient approach for combining NOMA and relaying techniques in such a way as to enhance the achievable rate from the source to the destination in the network. This paper examines the problem of joint power allocation among all the transmission phases during the operation of such networks. Based on the Karush-Kuhn-Tucker (KKT) condition and the second-order sufficient condition (SOSC), at least the local optimal solution is derived and analyzed. In addition, a new protocol for NDR networks based on cooperative communications is introduced and the associated joint power-allocation problem is examined. It is shown that this cooperative NDR (C-NDR) network further improves the achievable rate in some typical placements of the relays. Simulation results verify the correctness of the deviation and confirm the effectiveness of the proposed joint power-allocation method for both NDR and C-NDR networks.

Geometric programming applied to multipoint-to-multipoint MIMO relay networks

In this paper, we consider a relaying system which employs a single relay in a wireless network with distributed sources and destinations. Here, all source, destination, and relay nodes are equipped with multiple antennas. For amplify-and-forward relay systems, we confirm the achievable sum rate through a joint multiple source precoders and a single relay filter design. To this end, we propose a new linear processing scheme in terms of maximizing the sum rate performance by applying a blockwise relaying method combined with geometric programming techniques. By allowing the global channel knowledge at the source nodes, we show that this joint design problem is formulated as a standard geometric program, which can guarantees a global optimal value under the modified sum rate criterion. Simulation results show that the proposed blockwise relaying scheme with the joint power allocation method provides substantial sum rate gain compared to the conventional schemes.