상용 기성부품을 이용한 O-RAN 호환 기지국 시스템 구현

Abstract

Open Radio Access Network (O-RAN) standard has been proposed to separate the baseband signal processing unit from the Radio Frequency (RF) unit at base station system mainly for reducing the cost of base station systems through open-source interfaces between the two units. To satisfy the performance metrics in various scenarios, several fronthaul functional split options were presented by O-RAN. Amongst these options, the split option 7-2x is widely adopted in practical applications due to its excellent trade-off between the required bandwidth and RU overhead. In this paper, we present a hardware implementation of a base station system that is compliant with the Category B of O-RAN split option 7-2x. It consists of O-DU and O-RU implemented with a commercial off-the-shelf Digital Signal Processor and RF transceiver, respectively. The performance of the proposed base station system is evaluated in terms of Bit Error Rate and received signal power as well as the required fronthaul bandwidth. Through various experimental tests, we have observed that the proposed system reduces the fronthaul bandwidth nearly by 89.7% compared to the conventional system that dose not employ the O-RAN standard.