Patent ID: 8346098

Claim:
A receiving apparatus, comprising: a photoelectric detector (PD), configured to generate high-rate or low-rate current signals according to optical signals projected on the PD and digitally modulated at a high or low rate; a first switch, connected to the PD, and configured to switch to output the high-rate or low-rate current signals, and output the high-rate current signals to a first transimpedance amplifier (TIA) or output the low-rate current signals to a second TIA; the first TIA, configured to amplify the received high-rate current signals into high-rate voltage signals; the second TIA, configured to amplify the received low-rate current signals into low-rate voltage signals; a first filter, connected to the first TIA, and configured to filter out noises of the high-rate voltage signals and reduce a noise bandwidth; a second filter, connected to the second TIA, and configured to filter out noises of the low-rate voltage signals and reduce a noise bandwidth; a first limiting amplifier (LA), configured to perform a limiting amplification on the filtered high-rate voltage signals; and a second LA, configured to perform a limiting amplification on the filtered low-rate voltage signals; a first rate detector, disposed between the first LA and the first CDR circuit, and configured to detect the limited digital voltage signals, and control the first switch to connect to the second TIA if the voltage signals are the low-rate voltage signals; and a second rate detector, disposed between the second LA and the second CDR circuit, and configured to detect the limited digital voltage signals, and control the first switch to connect to the first TIA if the voltage signals are the high-rate voltage signals.