Reducing fronthaul traffic with direct constellation mapping method

Abstract

Centralized RAN, which connects a centralized base band unit (BBU) to multiple remote radio units (RRUs), is one of the promising architectures because it enables the BBU to coordinate with distributed RRUs by using multiple-input multiple-output (MIMO) processing without control signaling among RRUs. However, fronthaul traffic between the BBU and RRUs increases and fronthaul link capacity is to be under strain due to increasing the number of RRUs in a same fronthaul network segment. In this paper, we propose a direct constellation mapping method to reduce the fronthaul traffic. And it is also shown that our proposed method can drastically reduce the required fronthaul link capacity with slight downlink throughput degradation by Monte-Carlo computer simulation.