Joint Power Allocation and Beamforming for Energy-Efficient Two-Way Multi-Relay Communications

Zhichao Sheng, Hoang Duong Tuan, Trung Q. Duong, H. Vincent Poor

Research output: Contribution to journalArticlepeer-review

24 Scopus citations


This paper considers the joint design of user power allocation and relay beamforming in relaying communications, in which multiple pairs of single-antenna users exchange information with each other via multiple-antenna relays in two time slots. All users transmit their signals to the relays in the first time slot while the relays broadcast the beamformed signals to all users in the second time slot. The aim is to maximize the system's energy efficiency (EE) subject to quality-of-service (QoS) constraints in terms of exchange throughput requirements. The QoS constraints are nonconvex with many nonlinear cross-terms, so finding a feasible point is already computationally challenging. The sum throughput appears in the numerator while the total consumption power appears in the denominator of the EE objective function. The former is a nonconcave function and the latter is a nonconvex function, making fractional programming useless for EE optimization. Nevertheless, efficient iterations of low complexity to obtain its optimized solutions are developed. The performance of the multiple-user and multiple-relay networks under various scenarios is evaluated to show the merit of the proposed method.

Original languageEnglish (US)
Article number7987795
Pages (from-to)6660-6671
Number of pages12
JournalIEEE Transactions on Wireless Communications
Issue number10
StatePublished - Oct 2017
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Computer Science Applications
  • Electrical and Electronic Engineering
  • Applied Mathematics


  • Two-way relaying
  • energy efficiency (EE)
  • information exchange (IE)
  • joint optimization
  • path-following algorithms
  • power allocation
  • quality-of-service (QoS)
  • relay beamforming


Dive into the research topics of 'Joint Power Allocation and Beamforming for Energy-Efficient Two-Way Multi-Relay Communications'. Together they form a unique fingerprint.

Cite this