This letter studies a joint design of fronthaul and radio access links for a cloud radio access network (C-RAN) with wireless fronthauling, where a baseband unit (BBU) controls a number of remote radio heads (RRHs) via wireless fronthaul links to communicate with user equipments. We first review a basic approach based on a single cell concept, whereby the RRHs operate as decode-and-forward (DF) relays. Then, a cooperative transmission from the RRHs based on decompress-and-forward (DCF) relaying is proposed, which is a standard concept in C-RAN. For both strategies, a problem of jointly optimizing the BBU and RRH operations is tackled with the goal of maximizing the weighted sum-rate subject to the BBU and per-RRH power constraints. For each formulated problem, an iterative algorithm is derived that achieves a sequence of monotonically nondecreasing objective values at each iteration. It is confirmed via numerical results that the DCF-based cooperative scheme significantly outperforms the DF-based single-cell approach.
Bibliographical noteFunding Information:
The work of S.-H. Park was supported in part by the National Research Foundation (NRF) of Korea funded by the Ministry of Science, ICT & Future Planning (MSIP) of Korea Government under Grant 2015R1A2A1A10076557. The work of K.-J. Lee was supported in part by the Basic Science Research Program through the NRF funded by the MSIP (NRF-2013R1A1A1060503; NRF-2016R1C1B2011921). The work of C. Song was supported in part by the NRF funded by the MSIP of Korea Government under Grant NRF-2015R1C1A1A02036927. The work of I. Lee was supported in part by the NRF funded by the Korea Government (MSIP) under Grant 2014R1A2A1A10049769. The associate editor coordinating the review of this manuscript and approving it for publication was Prof. Mohammad M. Mansour. (Corresponding author: K.-J. Lee.)
© 2016 IEEE.
- wireless fronthaul
ASJC Scopus subject areas
- Signal Processing
- Electrical and Electronic Engineering
- Applied Mathematics