Method for implementing DQPSK demodulation and apparatus thereof

• Main Authors: MO SHUANG, JIANG YOUSHAN, PAN ZHONGLING
• Format: Patent
• Language: Chinese; English
• Published: 07.01.2009
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

The invention provides a device for demodulating the DQPSK modulation signals in an optical communication system and a method thereof. The DQPSK demodulation device and the method are based on the principle of a delay line interferometer DLI, and the device consists of two DLI demodulation modules. Along an input optical path, the key elements of the DQPSK demodulation device and the method comprise an input YVO4 collimator, a spectroscope and two delay line interferometer modules in which two outputs of the spectroscope respectively can enter sequentially, wherein, along the input optical path, each DLI module comprises a polarization spectroscope PBS, a rotation disc, a wave plate, the delay line interferometer, two output YVO4 collimators, and the like, in sequence. The DQPSK demodulation device and the method have the advantages that the free space optical design is adopted, the temperature stability is good, the volume is small, and the modularization is easy to be realized; the two DLI demodulation modu