Equal optical path difference processing method and device

Abstract

The invention discloses an equal optical path difference processing method and device, and the method comprises the steps: enabling four optical fibers of an optical mixer to be respectively welded with two I-path optical fibers of a first detector and two Q-path optical fibers of a second detector; measuring an optical path difference between the I-path optical fiber and the Q-path optical fiberby adopting an oscilloscope; and cutting the two Q-path optical fibers according to the optical path difference and then carrying out secondary welding, so that the difference between the length of the Q-path optical fibers and the length of the I-path optical fibers is within an error range. According to the equal optical path difference processing method disclosed by the invention, the optical path difference between the I-path optical fiber and the Q-path optical fiber can be accurately tested, and the longer Q-path optical fiber is processed by adopting a secondary welding process after the optical path difference is calculated, so the length of the Q-path optical fiber is basically equal to that of the I-path optical fiber.

Description

technical field [0001] The invention belongs to the technical field of communication, and in particular relates to a method and a device for equal optical path difference processing. Background technique [0002] In the laser BPSK (Binary Phase Shift Keying, Binary Phase Shift Keying) coherent demodulation communication system, the block diagram of the coherent demodulation module is as follows figure 1 shown. The optical mixer is the core component of the coherent demodulation module. Its function is to mix the local oscillator light with the same polarization direction and similar or the same frequency with the signal light to obtain the phase information of the signal light. One optical signal and the local oscillator optical signal enter from the optical mixer, and the optical signal is demodulated by the phase shifting method. The optical mixer outputs two sets of I and Q optical signals, and the Q optical signal is a phase shift of the optical signal by 90 °, it is r...

AI Technical Summary

Problems solved by technology

However, in optical communication, the optical devices are interconnected through the method of optical fiber fusion, and the fusion point of the optical fiber cannot be disconnected after fusion, and the cross-connection test cannot be performed.

If the cross-connection test is performed after disconnection, the length of the optical fiber will change and there is no reference point. Therefore, the above-mentioned direct and cross-connection test cannot be performed, and only a new measurement method can be used for testing.

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