Patent ID: 8301039
Filing Date: 2012-10-30
Classification: H04B

Abstract:
1. A delay processing apparatus that is used with an analog-digital converter that converts, into digital signals, an in-phase signal and a quadrature signal that are obtained by demodulating multi-level phase modulated light, and a processor that carries out digital signal processing on the digital signals from the analog-digital converter to recover data, the delay processing apparatus comprising: a delay device that provides a delay amount to at least one of the in-phase signal and the quadrature signal; and a delay control section that provides a feedback control on the delay amount provided by the delay device based on a quality of the signals when the in-phase signal and the quadrature signal, to the at least one of which the delay amount is provided at the delay device, are converted into digital signals by the analog-digital converter, and the digital signal processing is carried out at the processor.