Energy efficient precoding C-RAN downlink with compression at fronthaul
Nguyen, Kien-Giang; Vu, Quang-Doanh; Juntti, Markku; Tran, Le-Nam (2017-07-31)
K. G. Nguyen, Q. D. Vu, M. Juntti and L. N. Tran, "Energy efficient preceding C-RAN downlink with compression at fronthaul," 2017 IEEE International Conference on Communications (ICC), Paris, 2017, pp. 1-6. doi: 10.1109/ICC.2017.7996949
© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
This paper considers a downlink transmission of cloud radio access network (C-RAN) in which precoded baseband signals at a common baseband unit are compressed before being forwarded to radio units (RUs) through limited fronthaul capacity links. We investigate the joint design of precoding, multivariate compression and RU-user selection which maximizes the energy efficiency of downlink C-RAN networks. The considered problem is inherently a rank-constrained mixed Boolean nonconvex program for which a globally optimal solution is difficult and computationally expensive to find. In order to derive practically appealing solutions, we invoke some useful relaxation and transformation techniques to arrive at a more tractable (but still nonconvex) continuous program. To solve the relaxation problem, we propose an iterative procedure based on DC algorithms which is provably convergent. Numerical results demonstrate the superior of the proposed solution in terms of achievable energy efficiency compared to existing schemes.
- Avoin saatavuus