Patent ID: 7389056
Filing Date: 2008-06-17
Classification: H03F,H03G,H04B,H04L

Abstract:
1. An optical receiver, comprising: a photodetector for detecting an input signal; a clock switching circuit including an amplifying part having a preamplifier configured to control a bandwidth for amplifying the input signal by varying a feedback resistance according to a control signal; an AGC part configured to control a level of an output signal of the preamplifier to a fixed level and to output the level-controlled signal, the input signal corresponding to one of a plurality of input signals with differing transmission speeds; a control signal generating part configured to determine a band of an output signal from the amplifying part and to generate the control signal based on the determined band; a correction signal generating part configured to generate a correction signal for correcting the control signal, based on the output signal of the preamplifier and a clock; a clock switching part configured to detect a transmission speed of the input signal based on a corrected control signal for adjusting the feedback resistance, which corrected control signal is obtained by correcting the control signal with the correction signal, to generate a standard clock that corresponds to a clock for an input signal with a maximum transmission speed of the differing transmission speeds, and switch a frequency of a clock for identifying the output signal of the amplifying part according to the transmission speed detection result; and a data identifying/reproducing part configured to sample an output signal from the AGC part, using the clock output by the dividing part, and to identify and reproduce data based on the sampled signal.