A case for assisted partial timing support using precision timing protocol packet synchronization for LTE-A

North American service providers are in the process of upgrading their radio access networks with next generation LTE equipment. They are finalizing a 4G rollout that involves highly stringent timing requirements, but in many cases they are relying on sole-source synchronization by using Global Navigation Satellite System (GNSS). Natural occurring disturbances, as well as unintentional radio frequency jamming, intentional jamming, and spoofing, make GNSS vulnerable to interference. This article presents a novel approach for addressing the issue of GNSS vulnerability by introducing a standard means of providing a redundant packet-based synchronization source for LTE base stations. It also describes how this new approach can mitigate noise caused by asymmetry and transit delay variation in packet networks.