This paper discusses a power save management method appropriate for the features of the fiber-optic access network based on Passive Double Star (PDS) topology, where PDS termination processing LSIs for the Optical Network Unit (ONU) operate intermittently and the usage rate is low at the residential customer. We developed PDS termination processing LSIs for the ONU, performed power management, and evaluated the degree of consumed power.

This paper describes a novel adaptive clock recovery method that uses proportional-integral-derivative (PID) control. The adaptive clock method is a clock recovery technique that synchronizes connected terminals via packet networks, and will be indispensable for circuit emulation services in the next generation Ethernet. Our adaptive clock method simultaneously achieves a short starting-time, accuracy, stable recovery clock frequency, and few buffer delays using the PID control technique. We explain the numerical simulations, experimental results, and circuit designs.