Patent ID: 11923909
Assignee: BEIJING ZHONGKE GUOGUANG QUANTUM TECHNOLOGY CO., LTD.
Field: Telecommunications (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 5:
6. The self-coherent receiver based on polarization-independent delay interferometers according to claim 1, wherein the first polarization-independent delay interferometer comprises an eleventh polarization beam splitter, a fourth beam splitter, a fifth beam splitter, a seventh long-arm optical fiber, a seventh short-arm optical fiber and a twelfth polarization beam splitter;
the eleventh polarization beam splitter is configured to polarization-split the first signal light component to generate a first polarized signal light component and a second polarized signal light component;
the fourth beam splitter, the fifth beam splitter, the seventh long-arm optical fiber and the seventh short-arm optical fiber constitute a first Mach-Zehnder interferometer, which is configured to perform a self-interference on the first polarized signal light component to generate a first polarization interference optical signal and a second polarization interference optical signal; and to perform a self-interference on the second polarized signal light component to generate a third polarization interference optical signal and a fourth polarization interference optical signal;
the eleventh polarization beam splitter is further configured to polarization-combine the first polarization interference optical signal and the third polarization interference optical signal to generate the first interference optical signal; the twelfth polarization beam splitter is configured to polarization-combine the second polarization interference optical signal and the fourth polarization interference optical signal to generate the second interference optical signal;
the second polarization-independent delay interferometer comprises a thirteenth polarization beam splitter, a sixth beam splitter, a seventh beam splitter, an eighth long-arm optical fiber, an eighth short-arm optical fiber, a fourth phase shifter and a fourteenth polarization beam splitter;
the thirteenth polarization beam splitter is configured to polarization-split the second signal light component to generate a third polarized signal light component and a fourth polarized signal light component;
the sixth beam splitter, the seventh beam splitter, the eighth long-arm optical fiber, the eighth short-arm optical fiber and the fourth phase shifter constitute a second Mach-Zehnder interferometer, which is configured to perform a self-interference on the third polarized signal light component to generate a fifth polarization interference optical signal and a sixth polarization interference optical signal; and to perform a self-interference on the fourth polarized signal light component to generate a seventh polarization interference optical signal and an eighth polarization interference optical signal;
the fourth phase shifter is configured to adjust a phase of an optical signal transmitted through the eighth short-arm optical fiber, so that a phase difference between the optical signal transmitted through the eighth short-arm optical fiber and an optical signal transmitted through the eighth long-arm optical fiber is π/2;
the thirteenth polarization beam splitter is further configured to polarization-combine the fifth polarization interference optical signal and the seventh polarization interference optical signal to generate the third interference optical signal; the fourteenth polarization beam splitter is configured to polarization-combine the sixth polarization interference optical signal and the eighth polarization interference optical signal to generate the fourth interference optical signal.