Application research of the balance detector on coherent detection techniques

摘要

The principles of coherent detection and balanced detectors are analyzed respectively in this article. It mainly talked about the balance detector applications in coherent detection. Obtained by the theoretical analysis that we can not only make full use of the local oscillator optical power but also eliminate the noise of the LO light more effectively by using the balanced detector. The most important is that it can improve the SNR of the system. This paper also makes a research on the factors that affect the performance of the balanced detector. The simulation results show that the response of the photo-diode consistency should be gain at least 90% in order to improve the SNR effectively. It further validates that the laser intensity noise indeed declined by using the balanced detector.