Patent ID: 7076177

Claim:
An apparatus, comprising: a converter for converting an input optical signal to an original electrical signal; an identification unit for receiving said original electrical signal, for generating a first signal comprising said original electrical signal delayed by a predetermined quantity of time, for generating a second signal comprising said original electrical signal not delayed, for comparing said first and second signals, for forming a third signal in dependence upon said comparing of said first and second signals, and for detecting a bit rate in dependence upon said third signal; a clock generator for generating a separate reference clock signal in dependence upon said detected bit rate; and a recovery unit for recovering an input clock signal and data from said input optical signal in dependence upon said reference clock signal; wherein said clock generator comprises a plurality of oscillators for generating clocking signals of different frequencies, said oscillators being selectively operated to generate said reference clock signal in dependence upon said bit rate detected by said identification unit; and wherein said identification unit further comprises: a first unit for delaying said original electrical signal, for performing an exclusive-OR operation upon said first and second signals, and for forming said third signal in dependence upon said exclusive-OR operation performed upon said first and second signals; and a second unit for low-pass filtering said third signal, and for detecting said bit rate directly from a voltage level of said low-pass filtered third signal and without using a phase locked loop; said second unit comprising: a low-pass filter for low-pass filtering said third signal; an analog-to-digital converter for receiving said low-pass filtered third signal, and for converting said low-pass filtered third signal from an analog signal to a digital signal; and a bit rate deriving unit for deriving said bit rate directly from a voltage level of said digital signal received from said analog-to-digital converter.