Outdoor Trial of an Analog-only Small Cell Unit with Millimeter-Wave Wireless Backhaul for Mobile Communication System

This paper analyzes the achievable signal quality of a novel system architecture for small cell units with integrated millimeter-wave wireless backhaul. In contrast to existing systems, the data signal on the backhaul link uses the same 3GPP compliant signal as with the access link serving the users. The small cell unit only consists of a simple frequency conversion from backhaul to access frequencies. The sufficient linearity and phase noise performance at 60GHz was proven in an outdoor long-distance trial with measurements of an LTE signal easily meeting the access link 3GPP ACLR and EVM requirements. Moreover, a successful outdoor test of our full end-to-end LTE mobile communication system with a commercial user device demonstrated the required high data rates.