A new IQ data compression scheme for front-haul link in Centralized RAN

In the Centralized-RAN (C-RAN), some baseband units (BBUs) are centralized in the same location, which is typically less than 20 km away from remote radio heads (RRHs) locally distributed. Each RRH is connected to BBUs via front-haul link by optical fibers which convey the digital IQ data by CPRI protocol. This paper proposes a new IQ data compression scheme with 1/2 compression ratio, which can be easily implemented by using both IQ bit width reduction and a common lossless audio compression scheme. Through performance evaluation, it is verified that the proposed method meets the requirements from an implementation point of view. By applying the proposed scheme to the front-haul link, the installation cost of optical fibers can be reduced by half.