Distributed Synchronization for Device-to-Device Communications in an LTE Network

We study the problem of distributed time and frequency synchronization for device-to-device communication in LTE [1]. LTE is an OFDMA system that crucially uses tight time and frequency synchronization between UEs and the base station for intracell and intercell interference coordination. For consistency with the cyclic prefix length and tone spacing used in LTE, we target an accuracy of a few microseconds for time synchronization and 150 Hz for frequency synchronization. We examine the problem both from a link and a system-level perspective. Link-level challenges involve designing a synchronization signal for computationally and energy efficient receiver algorithms, and system-level challenges involve achieving consistent timing using a distributed algorithm while leveraging the multiuser aspect of the problem to improve performance.