Complexity Effective Frequency and Sidelink Synchronization Algorithm for LTE Device-to-Device Communication Systems

Device-to-device (D2D) communication is considered as a major challenge in the long term evolution (LTE) network wherein devices directly communicate with each other. One of the key challenges in D2D sidelink is reliable and reduced-complexity synchronization. To address this issue, a computationally efficient sequential detection scheme for integer carrier frequency offset and sidelink identity is proposed in the LTE-D2D system. To perform the frequency offset detection without retrieving the sidelink identity, the conjugate relation between two primary sidelink synchronization sequences is exploited, which facilitates the detection tasks of frequency offset and sidelink identity to be decoupled. It is demonstrated from simulation results that the inherent property of the sidelink synchronization sequences is effectively used for joint detection of frequency offset and sidelink identity with significantly reduced complexity, compared to existing estimation schemes.