Beamforming in relay-assisted cognitive radio systems: A convex optimization approach

Karama Hamdi, Keyvan Zarifi, Khaled Letaief, Ali Ghrayeb

Research output: Chapter in Book/Report/Conference proceedingConference contribution

17 Citations (Scopus)

Abstract

Cognitive radio (CR) has been recently proposed as a promising technology to improve the spectrum utilization. In this paper, we consider the spectrum sharing between CR users and a licensed primary user (PU) in order to enhance the spectrum efficiency. In the considered scenario, the PU is located at a far position from the primary base station (PBS) which makes it difficult to obtain a successful transmission. In this case, the cognitive base station (CBS) at the vicinity of the primary network, offers its help to transmit the primary data. As a reward, the CR system will be able to share the spectrum with the primary system. With the deployment of multiple antennas at the CBS, quality-of-service (QoS)-aware spectrum underlay CR network is considered. In particular, we formulate a ''fair'' opportunistic spectrum sharing approach that determines the optimal beamforming weights in order to maximize the overall minimum throughput of the CRs while guaranteeing the QoS of the PU. The original optimization problem is non-convex and does not have any closed-form solution. However, using a convex optimization approach, we transform it to a convex form and find an approximate solution using standard numerical methods. Simulation results will demonstrate the effectiveness of the proposed approach.

Original languageEnglish
Title of host publication2011 IEEE International Conference on Communications, ICC 2011
DOIs
Publication statusPublished - 2011
Externally publishedYes
Event2011 IEEE International Conference on Communications, ICC 2011 - Kyoto, Japan
Duration: 5 Jun 20119 Jun 2011

Other

Other2011 IEEE International Conference on Communications, ICC 2011
CountryJapan
CityKyoto
Period5/6/119/6/11

    Fingerprint

ASJC Scopus subject areas

  • Computer Networks and Communications
  • Electrical and Electronic Engineering

Cite this

Hamdi, K., Zarifi, K., Letaief, K., & Ghrayeb, A. (2011). Beamforming in relay-assisted cognitive radio systems: A convex optimization approach. In 2011 IEEE International Conference on Communications, ICC 2011 [5962588] https://doi.org/10.1109/icc.2011.5962588