Real-time CPU-GPU demodulator for the LTE physical layer

Since the emergence of large public networks in the 80's, wireless communication protocols have been evolving constantly, forcing frequent changes to the hardware of base stations. This has triggered a lot of research about implementing network functions in software, especially those of the physical layer, in order to allow the use of generic processors in the base stations. However, achieving this goal requires very fast hardware to maintain real time operation. In this work, we describe a hardware system that combines a desktop CPU with a GPU for real time frame demodulation in the LTE protocol physical layer. Our experiments with worst-case LTE frames show that the making of a software-based LTE frame processor that operates in real time is possible with general-purpose hardware architectures such as the one described, thus opening the door for upscaling to complete base stations.