Adaptive bit truncation and restoration for baseband signal compression

Abstract

The distributed base station architecture is one of the good solutions to reduce the system complexity and manage the cellular mobile communication system more efficiently. Typical distributed base stations consist of base band units (BBUs) and remote radio heads (RRHs). RRHs are deployed apart from BBU and connected to it generally through a fiber optic cable. Compression of baseband signal is an efficient way to decrease the data rates on the fiber link between BBU and RRHs. This paper presents a compression and decompression scheme. It truncates least significant bits according to the largest absolute value in a block, thereby achieves lossy compression at each of I and Q data, respectively. It restores the signal by using proposed stuffing bits to suppress DC component in the signal and relieve signal to noise ratio degradation by compression and decompression. The simulation results suggest that the proposed scheme provides promising performance of error vector magnitude with low latency. It enables cost effective implementation since it does not require any multiply accumulate operation. Simple bit operations are needed in proposed scheme.