| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical receiver in an optical line terminal, that quickly performs a shift from a power saving operation to a normal operation and improves a power saving effect.SOLUTION: An optical receiver includes: voltage control oscillators (VCOs) 113a and 113b for generating clock signals; flip flops (FFs) 104a and 104b for logically identifying electric signals from an OE conversion part with the clock signals as triggers; and a media access control (MAC) block 108 for controlling the signal transmission timing of each optical network unit (ONU). The optical receiver also includes: switches (SWs) 114a and 114b for switching whether or not the clock signals are supplied to the FFs 104a and 104b; and operation control circuits 107a and 107b for controlling the SWs 114a and 114b. The operation control circuits 107a and 107b acquire from the MAC block 108, whether or not optical signals are input to the optical receiver, and controls the SWs 114a and 114b thereby to cut the supply of the clock signals from the VCOs 113a and 113b to the FFs 104a and 104b during a time period when the optical signals are not input to the optical receiver. |
