Polarization Controller for Coherent Optical Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In coherent optical reception systems, polarization-dependent loss and performance differences between polarization paths lead to disparities in signal quality, necessitating a method to compensate and enhance received signal quality.
Innovation Solution
A coherent optical reception system with a polarization controller that monitors signal intensity and quality, generating control signals to adjust the local oscillator (LO) light, using optical attenuators or interferometers to optimize LO light polarization and intensity, ensuring balanced signal quality across polarization paths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If polarization beam splitters are used to independently receive vertically and horizontally polarized light, then signal light can be restored after rotation, but signal quality differences arise between the two polarization paths due to polarization dependent loss and device performance variations
Solution Approach 1:
The patent implements a feedback mechanism where the signal processor monitors the quality of reception signals from both polarization paths and generates control signals accordingly. The polarization controller receives these control signals and adjusts the LO light polarization state to compensate for quality differences, creating a closed-loop system that continuously optimizes signal quality balance across both paths
Solution Approach 2:
The patent changes the polarization state parameter of the local oscillator light dynamically. By adjusting the polarization controller based on feedback about signal quality differences between paths, the system modifies the polarization parameters of LO light to equalize performance across vertically and horizontally polarized paths, compensating for polarization dependent loss and device variations
2Reliability
If the polarization state of LO light is fixed, then the system structure is simple, but signal quality cannot be optimized when polarization dependent loss occurs
Solution Approach 1:
The patent transforms the static polarization state of the local oscillator into a dynamic, adjustable parameter. The polarization controller enables real-time modification of LO light polarization based on monitored signal conditions, allowing the system to adapt to varying polarization dependent loss and performance differences without requiring complex redundant hardware structures
Solution Approach 2:
The system performs self-adjustment through the feedback loop where the signal processor automatically generates control signals based on detected signal quality, and the polarization controller automatically adjusts LO polarization accordingly. This self-service mechanism optimizes signal quality without requiring external manual intervention or complex additional control hardware
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively maximizes signal quality by equalizing signal qualities across polarization paths, improving overall system performance through controlled polarization and intensity adjustments of LO light.
Implementation Method 1
the signal light and local oscillator (LO) light are simultaneously received to cause optical beating and the beating components are received
Implementation Method 2
a polarization controller configured to transmit a signal for polarization control to the LO
Data Source
AI summary
Provided is an operation method of a coherent optical reception system. The operation method includes the following configurations. A coherent optical receiver configured to receive light from at least two light sources; a local oscillator (LO) configured to transmit first LO light to the coherent optical receiver, and a polarization controller configured to transmit a signal for polarization control to the LO, wherein the polarization controller is configured to transmit a first control signal to the LO on the basis of a first reception signal, and the LO is configured to transmit second LO light to the coherent optical receiver on the basis of the first control signal.