Design and Implementation of Multi-Channel RF Front End for Performance Analysis in srsRAN Based ORAN 5G Small Cell Network

5G Small cells are widely used to provide enhanced coverage to indoor spaces and densely populated areas. Future small cells are transitioning towards Open Radio Access Network (ORAN) technology in which RAN is disintegrated into different components. Small Cell testbeds provide a controlled platform to test and optimize the ORAN 5G network performance in the lab. Radio Frequency Front End (RFFE) is a critical part of 5G small cell radio unit (RU), consisting of transmit (Tx) and receive (Rx) channels for amplification of downlink (DL) and uplink (UL) RF signals. This paper presents a RFFE with two independent Tx and two independent Rx channels (2T2R) designed for a 5G small cell testbed, operating in 5G sub-6 GHz frequency band. In Tx mode, the RFFE provides > 27dBm average output power at the antenna port. The gain of each Rx channel is kept near 20dB with the selection of devices having very low noise figure. This front end has been integrated with srsRAN based 5G small cell testbed in the lab and tested in a live private 5G network. Significant improvement in the 5G network performance has been observed based on Radio Access Network (RAN) key performance indicators (KPIs) including DL throughput, Reference Signal Received Power (RSRP), and latency.