Segmented Optical Transmitter Timing Control Under Delay Drift
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical DACs face challenges in dynamically adjusting timing between segments during device operation due to dynamic fluctuations in delay amounts caused by temperature changes and voltage fluctuations, which affect signal quality.
Innovation Solution
An optical transmitter with a controller that adjusts the timing of multiple segments by switching bit data assignments and using a delay adjusting unit to optimize timing based on real-time monitoring of optical signals, allowing continuous timing adjustment during operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fixed delay adjustment is performed at factory shipment or after device installation, then timing alignment between segments is achieved initially, but the system cannot adapt to dynamic fluctuations in delay amounts caused by temperature and voltage changes during operation
Solution Approach 1:
The patent implements dynamic delay adjustment by making the delay amount variable during device operation. The control unit changes the delay amount based on monitored output light, enabling the system to adapt to temperature and voltage fluctuations. This transforms the static delay adjustment into a dynamic process that maintains signal quality under varying conditions.
Solution Approach 2:
The patent employs feedback control by monitoring the output light of the optical modulator and using this information to adjust the delay amount. The control unit continuously monitors the output and modifies the delay accordingly, creating a closed-loop system that maintains optimal timing alignment despite environmental changes.
2Productivity
If multiple segments are used in the optical modulator to achieve high-capacity transmission, then transmission capacity is improved, but timing discrepancies between segments occur due to unequal wiring lengths and propagation delays
Solution Approach 1:
The patent applies different delay amounts to different segments of the optical modulator. By individually adjusting the delay for each segment based on its specific characteristics (wiring length, propagation delay), the system achieves precise timing alignment across all segments while maintaining the benefits of multiple segments for high-capacity transmission.
Solution Approach 2:
The patent changes the delay parameter dynamically to compensate for timing discrepancies between segments. By adjusting the delay amount as a variable parameter rather than a fixed value, the system can optimize timing alignment for each segment while maintaining high transmission capacity through the use of multiple segments.
3Ease of manufacture
If electrical DAC is used to convert digital signals to analog signals, then signal conversion is achieved, but power consumption increases due to the need for electrical DAC and linear driver
Solution Approach 1:
The patent replaces the electrical DAC and linear driver architecture with an optical-based approach. By using an optical modulator with multiple segments and binary drivers, the system performs the digital-to-analog conversion function optically rather than electrically, thereby eliminating the power-hungry electrical DAC and reducing overall power consumption while maintaining signal conversion capability.
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 solution ensures consistent signal quality by dynamically adjusting timing between segments, accommodating temperature and voltage fluctuations, thereby maintaining optimal signal integrity.
Implementation Method 1
an optical modulator that modulates an optical signal
Implementation Method 2
three or more segments arranged in series along one or both of two optical waveguides of a Mach-Zehnder interferometer
Data Source
AI summary
An optical transmitter includes: an optical modulator that modulates an optical signal, and has three or more segments arranged along one or both optical waveguides of a Mach-Zehnder interferometer, two or more types of input bit data being input to the segments of the optical modulator; an encoder that obtains bit data for multiple bits by converting the input bit data to code for modulation performed by the optical modulator, the encoder outputting the obtained bit data to any of the segments; a switch that switches the bit data output by the encoder to a different one of the segments; a delay adjusting unit that adjusts delay between the segments; and a controller that instructs the switch to switch the bit data to the different one of the segments and notifies the switch of an amount of delay for the delay adjusting unit, based on monitoring of the optical signal modulated by the optical modulator.