Performance analysis of NLOS small cell backhaul using 17GHz point-to-point prototype radio

Dense deployment of Small Cell Access Networks (SCAN) at street level has generally been accepted as a solution to improve capacity, coverage and reduce operational expenses in 5G access networks. This deployment strategy necessitates new cost-effective, high capacity, scalable and flexible backhaul solutions especially in urban environments where traditional solutions, such as fiber and Digital Subscriber Line (DSL) are too expensive and time consuming to deploy. Traditional microwave solutions have capacity and coverage limitations. The new SCAN backhaul systems must have Non-Line-of-Sight (NLOS) and Self-Organizing-Network (SON) capabilities to address the coverage and cost problems. In earlier work we proposed a NLOS Small Cell Backhaul (SCB) system based on diffracted signals where Cognitive Radio Technology (CRT) is proposed to add intelligence to the radio devices, giving the system SON capabilities expected of 5G systems. NLOS operation and Millimeter Wave (mmW) technology are proposed to address the coverage and capacity problems respectively. In this paper experimental results of NLOS radio link and QoS performance measurements for a prototype 17GHZ radio system designed for use as a SCB system are presented. The system addresses the cost problem by using unlicensed spectrum bands and diffracted signals to enable NLOS operation, thus addressing the street level to roof top backhaul coverage problem. The results obtained show that NLOS links that meet the radio and QoS performance requirements of small cell backhaul links can be established in an urban canyon type of environment.