Patent ID: 8126334

Claim:
A burst mode transceiver comprising: a transmitter for generating and transmitting a ranging signal including alternating 0 and 1 values at a fundamental frequency along a fiber strand; a receiver for detecting a return ranging signal along said fiber strand, said return ranging signal including alternating 0 and 1 values at a fundamental frequency, harmonic signals of said fundamental frequency and noise signals induced along said fiber strand; a transimpedance amplifier coupled to said receiver for receiving incoming signals including said return ranging signal; and a signal detect circuit coupled to an output of said transimpedance amplifier, including: a band pass filter, said band pass filter allowing only return ranging signals having 0 and 1 values at the fundamental frequency of the ranging frequency to pass; a signal detector coupled to an output of said band pass filter; a low pass filter coupled to an output of said signal detector; and a comparator coupled to an output of said low pass filter, said comparator comparing the output from said low pass filter to a threshold value, said comparator asserting a signal detect signal if said output is greater than said threshold value.