PON SYSTEM, SUBSCRIBER-SIDE DEVICE, STATION-SIDE DEVICE, AND COMMUNICATIONS METHOD

摘要

A PON system comprises an ONU (2) and an OLT (1). The OLT (1) further comprises a buffer (10) for storing downstream data; a transmission timing determination unit (14) that determines a data transmission period of the downstream data on a per band update cycle basis; and a PON control unit (19) that adds the data transmission period to a gate frame and transmits same. The ONU (2) further comprises a light receiving device (27) and a frame division unit (28), which carry out a prescribed reception process upon the downstream data that is received from the OLT (1); and a reception timing instruction unit (29), which transitions the light receiving device (27) and the frame division unit (28) to either a power conservation state or a normal operation state on the basis of the data transmission period included within the gate frame.