Optical Module Impedance Matching via Scattering Parameter Calculation
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Solution Overview
Problem
Conventional optical modules face challenges with increasing power consumption and limited operating temperature support, leading to suboptimal performance and higher costs due to poor heat dissipation and impedance mismatch issues in passive optical network systems.
Innovation Solution
An optical assembly with a microcontroller and matching network that adjusts impedance by calculating and matching scattering parameters between the laser diode driver and the optical module, using a memory to store parameters and adjust resistor, inductor, or capacitor values in the matching network to optimize impedance matching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If optical modules are placed closer together to increase port density, then port density is improved, but heat dissipation condition deteriorates leading to higher operating temperature
Solution Approach 1:
The patent divides the electronic functions into separate modules: the optical module contains only optical components, while the electronic chip (LDD, LA, MCU) is placed on the communications board. This segmentation allows optical modules to be arranged more closely without exacerbating heat issues, as the heat-generating electronic components are separated onto the board level.
Solution Approach 2:
The patent introduces a matching network as an intermediary component between the laser diode driver and the optical module. This matching network optimizes impedance matching and signal quality, enabling better performance without requiring increased power consumption or closer spacing that would worsen heat dissipation.
2Speed
If more functions and channels are added to optical modules to increase data rate, then communication capability is improved, but power consumption increases
Solution Approach 1:
The patent extracts the electronic processing functions (LDD, LA, MCU) from the optical module and places them on the communications board. This allows the optical module to maintain lower power consumption while the board-level electronics provide the additional functions and channels needed for higher data rates.
Solution Approach 2:
The patent implements dynamic impedance matching through the matching network, which can adjust its characteristics based on operating conditions. This dynamic optimization allows the system to achieve higher data rates with improved power efficiency by ensuring optimal signal transmission without excessive power consumption.
3Productivity
If optical modules operate at higher temperatures to support multiple modules on same board, then port density is improved, but manufacturing cost increases
Solution Approach 1:
By segmenting the system into optical modules and electronic boards, the patent allows standard-temperature optical modules to be used alongside heat-dissipating board electronics. This avoids the need to manufacture expensive high-temperature optical modules while still achieving high port density through optimized board-level heat management.
4Device complexity
If impedance matching is not optimized, then device complexity is reduced, but signal quality deteriorates
Solution Approach 1:
The matching network serves as an intermediary component that handles impedance matching between the laser diode driver and optical module. This dedicated matching component ensures optimal signal quality without requiring complex integrated impedance control within the optical module itself, thus maintaining simplicity while improving reliability.
Data Source
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AI summary
Embodiments of the present invention provide a passive optical network system, an optical assembly, and a method for adjusting matched impedance of the optical assembly. The optical assembly includes an optical module and a communications board. An optical component, a first memory, and an edge connector are disposed on the optical module, and the first memory is configured to store a first scattering parameter of the optical module and an operating parameter of the optical component. A connector, an electrical chip, and a matching network are disposed on the communications board, and the optical module is connected to the connector by using the edge connector. The electrical chip includes a micro controller and a laser diode driver, the micro controller and the laser diode driver are connected to the connector via the matching network, and the communications board stores a second scattering parameter that is between the laser diode driver and the connector. The micro controller is configured to calculate a third scattering parameter that is between the laser diode driver and the optical module based on the first scattering parameter and the second scattering parameter, and adjust matched impedance of the matching network. The optical assembly can be used to reduce power consumption of the optical module.