Joint Coding and Stochastic Data Transmission for Uplink Cloud Radio Access Networks

• Published in: IEEE communications letters Vol. 18; no. 9; pp. 1619 - 1622
• Main Authors: Hong, Song-Nam, Kim, Joongheon
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.09.2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Encoding; Joints; Optimization; Radio access networks; Signal to noise ratio; Stochastic processes; Telecommunications systems; Uplink; stochastic network optimization; quantize and forward; Cloud radio access network
• ISSN: 1089-7798; 1558-2558
• DOI: 10.1109/LCOMM.2014.2343614

We study the uplink cloud radio access networks using quantize and forward as an underlying relaying scheme. In all previous works, each radio unit (RU) is assumed to choose a compression rate equal to an instantaneous backhaul capacity. In this letter, we consider a more general network model for which each RU is equipped with a queue whose arrival rate is equal to a compression rate and departure rate is equal to a current backhaul capacity. For each time slot, it can choose a higher compression rate than the given backhaul capacity as long as the queue is stable. Using the principle of stochastic network optimization, we present a distributed algorithm to find the compression rate of each RU such that a time-averaged sum-rate is maximized subject to the queue stability. Under the optimal compression policy, some of RUs are active with a higher compression rate and the others are silent, for a given time slot, which is completely different from the conventional approach that all RUs are always active.