Patent ID: 7453554
Filing Date: 2008-11-18
Classification: G01S

Abstract:
1. A phase measurement method, comprising: inputting a predetermined voltage to a photoelectric converter; receiving an optical signal; converting the optical signal into an electrical signal; mixing the electrical signal with a mixed signal to generate an output signal; filtering the output signal to generate an IF signal; sampling the IF signal to generate a sampled signal with an amplitude value; determining whether the amplitude value falls within a predetermined amplitude range or not; modifying the predetermined voltage and receiving the optical signal until the amplitude value falls within the predetermined amplitude range when the amplitude value does not fall within the predetermined amplitude range; calculating a first phase value in accordance with the sampled signal when the amplitude value falls within the predetermined amplitude range; determining whether the predetermined voltage has been modified or not; calculating a compensating phase value in accordance with the modified predetermined voltage when the predetermined voltage has been modified; and summing up the first phase value and the compensating phase value to generate a second phase value.