5G Wireless Emulator for Evaluating Downlink Communication Under Multicell Interference

Abstract

In this paper, we propose and develop a fifth-generation mobile communication system (5G) emulator that can evaluate the entire downlink (DL) communication of a 5G between multiple base stations (BSs) and multiple user equipments (UEs), including the effect of multicell interference in a virtual cyberspace without conducting outdoor experiments. For implementation, we used the 5G development platform based on OpenAirInterface (5G-OAI) running on a Linux machine. However, the default 5G-OAI cannot construct a system capable of evaluating the effects of multicell interference. To evaluate the impact of multicell interference using a 5G-OAI-based emulator, if a straightforward implementation is to be used, it is necessary to expand the emulator to run many BSs in parallel. However, achieving this on a Linux machine requires a significant amount of additional computation, making it impossible to implement. In the proposed 5G emulator, we implemented a mechanism for generating pseudo-interference signals, thereby achieving the effects of multicell interference with ultra-low computational cost (reduction of more than 98%). We also evaluated the block error rate (BLER) characteristics in the 3GPP urban macro scenario, a multicell environment specified by 3GPP, and demonstrated that we can emulate BLER with a root-mean-square error of approximately 0.03.