Communication system and synchronization control method

摘要

A sender transmits to a receiver an optical signal that is phase-modulated in accordance with source data and a basis stored in a memory. The receiver phase-modulates the received optical signal in accordance with a basis, obtains detection data through interference, and stores the detection data in a memory. An inter-device address difference (G D ) and an intra-device address difference (D I ) are provisionally set. The detection data are checked against the source data while sequentially changing the values of G D and D I within a predetermined adjustment range. Based on the result of this checking, G D and D I are determined.