I/Q Transponder Phase Rotation Control for FSK-SV Links
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In communication systems using the FSK-SV method, phase rotation direction reversal can lead to bit inversion and signal offset, causing poor signal quality, especially when automatic control is required between transponders without SDN intervention.
Innovation Solution
A transmission system with first and second transponders, each equipped with an I/Q modulator, uses a frequency modulation scheme to set appropriate phase rotation modes by exchanging FSK-SV signals, allowing autonomous adjustment of phase rotation states between the transponders to prevent bit inversion and signal offset.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If FSK-SV method is used for automatic control between transponders, then control automation is improved, but phase rotation direction reversal causes bit inversion and signal offset
Solution Approach 1:
The patent applies preliminary action by detecting the phase rotation direction of the optical signal before FSK-SV communication occurs. The system determines whether the phase rotation direction is reversed and adjusts the I/Q modulator settings in advance to prevent bit inversion and signal offset, ensuring reliable automatic control from the outset
Solution Approach 2:
The patent implements feedback by continuously monitoring the phase rotation direction of optical signals and using this information to adjust the I/Q modulator settings. The system detects the actual phase rotation direction and feeds this information back to correct any reversals, maintaining signal quality during automatic FSK-SV control operations
2Adaptability or versatility
If I/Q modulator is used for optical signal modulation, then communication functionality is improved, but characteristics of the modulator or ABC circuit may cause phase rotation direction reversal
Solution Approach 1:
The patent applies self-service by enabling the I/Q modulator system to automatically detect and correct its own phase rotation direction issues. The system monitors its own output signal characteristics and adjusts its internal settings without external intervention, making the modulator self-correcting regarding phase rotation reversals
Solution Approach 2:
The patent implements parameter changes by adjusting the phase difference between the I-arm modulator and Q-arm modulator by π when phase rotation reversal is detected. This parameter adjustment corrects the phase rotation direction while maintaining the communication functionality of the I/Q modulator
3Device complexity
If phase rotation direction is not monitored, then device complexity is reduced, but bit inversion and signal offset occur
Solution Approach 1:
The patent replaces complex mechanical or manual monitoring systems with an optical-based detection method. By using the optical signal itself to indicate phase rotation direction through frequency shift keying, the system achieves reliable phase monitoring without adding complex mechanical control devices
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
This method enables bi-directional autonomous control, ensuring appropriate phase rotation states are maintained, thus improving signal quality and reliability in FSK-SV communication without requiring SDN controller instructions.
Implementation Method 1
an I/Q modulator configured to rotate a phase of a light signal inputted into the I/Q modulator according to a drive signal to generate an optical output signal
Implementation Method 2
a FSK modulator configured to superimpose an FSK signal on the optical modulated signal by a frequency shift keying method
Data Source
AI summary
A transmission system includes a first transponder including a first I/Q modulator, and a second transponder including a second I/Q modulator, and configured to communicate with the first transponder using a frequency modulation scheme, wherein the first transponder is configured to set a first phase rotation mode in a first state for first light signal output from the first I/Q modulator, and transmit, to the second transponder, a first command to specify a second phase rotation mode for second light signal output from the second I/Q modulator, and the second transponder is configured to set, in response to the first command, the second phase rotation mode in a state specified by the first command.