Cooperative caching and coordinated beamforming technique for cognitive radio networks

IET Signal Processing

Sangarapillai Lambotharan¹  Gan Zheng¹  Ashraf Bsebsu¹ 

[1] Signal Processing and Networks Research Group Wolfson School Loughborough University Loughborough UK;

关键词: cognitive radio;    content caching;    multiplexing gain;    zero‐forcing coordinated beamforming;   

DOI  :  10.1049/sil2.12043

来源: DOAJ

【 摘 要 】

Abstract Scarcity of frequency spectrum is one of the main issues in wireless communications. Cognitive radio networks (CRNs) have been considered as an effective way of improving the spectrum efficiency by opportunistically using the spectrum resources through appropriate cooperation between primary and secondary networks. Exploitation of content caching in CRNs can enhance the system performance and reduce the backhaul cost and delay. In this paper, we propose a combined caching strategy and base station coordination in CRNs to achieve a proper balance between the signal cooperation gain and the content diversity gain. Depending on the availability and placement of the requested content, we propose a zero‐forcing coordinated beamforming technique to simultaneously transmit the most popular contents that are cached in every secondary base station and achieve the signal cooperation multiplexing gains, also we propose a maximum ratio transmission technique to deliver the less popular contents which are cached in different secondary base stations and achieve the caching diversity gain. Enumeration of the solution space search is used to obtain the optimal cache solution. Numerical results show that our proposed solution outperforms the cooperative caching and transmission solution proposed where only a maximum ratio transmission technique is used.

【 授权许可】

Unknown