Issue link: https://read.uberflip.com/i/1423190
LoRa Alliance ® Whitepaper Page 3 of 49 LoRaWAN ® Gateways Radio Coexistence Issues and Solutions Copyright ©2021 LoRa Alliance, Inc. All rights reserved. www.lora-alliance.org 1 INTRODUCTION When deploying a low-power wide-area network (LPWAN), as any radiocommunications network, the choice of the gateway installation site is critical. An optimized site provides the operator several benefits, such as a better coverage area, a better quality of service, and an optimized number of deployed gateways. This results in a cost reduction for the deployment itself and an improved quality of service during the exploitation of the network. In any defined area, the number of available sites offering optimal coverage is obviously limited. Site sharing is often favored in urban and suburban areas where there is a shortage of available sites or complex radio planning requirements. These sites are, in most cases, already being used by other radio systems, such as cellular base stations (GSM/UMTS/LTE) or TV emitters. In many use cases, the LoRaWAN ® gateways are therefore colocated with those emitters, and special care must be taken during the installation to avoid any interference. More generally, when deploying LoRaWAN gateways, especially in urban areas, it is necessary to consider all the radio systems in the near environment. Figure 1: Example of Kerlink Wirnet™ iBTS Compact gateway deployed in Mumbai, India This white paper details the phenomena which could cause desensitization of LoRaWAN gateways because of the colocated transmitters, such as: • Out-of-band blocking • In-band blocking • Third-order intermodulation • Generation of out-of-band noise (spurious emissions) The paper also provides some recommendations to avoid desensitization by using: • Radio frequency (RF) filters by design – embedded in the gateway • External cavity filters, for specific harsh environments • Installation recommendations to minimize interference