Using Graphics Processing Units in an LTE Base Station

Base stations have been built from ASICs, DSP processors, or FPGAs. This paper studies the feasibility of building wireless base stations from commercial graphics processing units (GPUs). GPUs are attractive because they are widely used massively parallel devices that can be programmed in a high level language. Base station workloads are highly parallel, making GPUs a potential candidate for a cost effective programmable solution. In this work, we develop parallel implementations of key kernels to evaluate the merits of using GPUs as the baseband signal processor. We also study the mapping method of key kernels onto a multi-GPU system to minimize the number of required GPUs and the overall subframe processing latency. Our results show that the baseband subsystem in an LTE base station, which supports ≤150 Mbps peak data rate, can be built with up to four NVIDIA GTX 680 GPUs and commercial motherboards. We also show that the digital processing subsystem for a 75 Mbps LTE base station can be built using two NVIDIA GTX 680 GPUs with power consumption of 188 W.