| 摘要 |
A direct detection method and apparatus for a fiber optic acoustic sensor array systems using an in line Michelson sensor TDM array and an interferometric section having two acousto-optic modulators that produce optical pulses that are frequency shifted with respect to each other. Direct detection is accomplished according to the equation: I(t) = A + B cos[.phi.1 -.phi.2 + 2.pi. (f1 - f2) t], with the phase shift difference .phi.1 - .phi.2 between two paths containing the acoustic phase information and the frequency f1 - f2 being the difference between the RF frequencies for the two acousto-optic modulators.
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