Title :
Joint Optimization Scheme for Power Allocation and Subcarrier Pairing in OFDM-Based Multi-Relay Networks
Author :
Zhikang Zhou ; Qi Zhu
Author_Institution :
Sch. of Telecommun. & Inf. Eng., Nanjing Univ. of Posts & Telecommun., Nanjing, China
Abstract :
We consider an OFDM-based multi-relay network in this letter, where a certain subcarrier pair can be forwarded by the source node and multiple relays to provide space diversity. A joint optimization scheme for power allocation (PA) and subcarrier pairing (SP) is proposed to maximize the total end-to-end transmission rate under a total power constraint. The optimization problem is simplified by introducing the definition of equivalent channel gain, and a new PA scheme based on the Cauchy-Schwarz inequality is provided in this letter. Then a suboptimal scheme, which can provide similar performance with lower computation complexity, is proposed. Simulation results show that the proposed schemes outperform other schemes with or without space diversity.
Keywords :
OFDM modulation; computational complexity; diversity reception; optimisation; relay networks (telecommunication); resource allocation; Cauchy-Schwarz inequality; OFDM; computation complexity; equivalent channel gain; joint optimization; multirelay networks; power allocation; source node; space diversity; subcarrier pairing; Complexity theory; Joints; OFDM; Optimization; Relays; Resource management; Signal to noise ratio; Orthogonal frequency division multiplexing (OFDM); cooperative networks; multi-relay; power allocation (PA); subcarrier pairing;
Journal_Title :
Communications Letters, IEEE
DOI :
10.1109/LCOMM.2014.2319256
