Single-Wavelength Bidirectional Transceiver Fusion Coupler
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bidirectional transceivers in avionics networks require labor-intensive wavelength matching, and previous designs with beam splitters suffer from high cross-talk and reflection issues, making them unsuitable for large-scale switch networks.
Innovation Solution
A pluggable single-wavelength bidirectional transceiver with an integrated 2x1 fusion coupler replaces the beam splitter, providing low back reflection and eliminating cross-talk, allowing for error-free operation over 100 meters in large-scale switching networks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a beam splitter is used in the optical subassembly to enable single-wavelength bidirectional operation, then the transceiver can operate at the same wavelength for transmit and receive, but large cross-talk and scattering of optical reflection occur which disable bidirectional link operation
Solution Approach 1:
The patent introduces an optical circulator as an intermediary device between the laser and the optical fiber. The circulator directs the laser's forward signal to the fiber while routing the reflected light from the fiber to the photodetector, preventing direct coupling of reflected light back to the laser and eliminating cross-talk and scattering issues that would otherwise disable bidirectional operation
Solution Approach 2:
The patent segments the optical path into distinct functional sections using the circulator: the transmit path (laser to fiber), the receive path (fiber to photodetector), and the reflection path (fiber back to circulator). This segmentation isolates the different optical signals and prevents harmful interactions between transmit and receive channels
2Reliability
If two wavelengths are used in bidirectional transceivers, then transmit and receive signals can be separated, but designers and installers face labor-intensive wavelength matching and frequent re-work in large-scale switch networks
Solution Approach 1:
The patent changes the wavelength parameter from two different wavelengths to a single wavelength for both transmit and receive operations. By using the optical circulator to manage signal directionality, the system eliminates the need for wavelength matching while maintaining reliable signal separation between transmit and receive channels
Solution Approach 2:
The optical circulator serves multiple functions: it acts as a directional coupler for the transmit signal, a separator for the receive signal, and a reflector isolator for backward-propagating light. This multi-functionality allows single-wavelength bidirectional operation without requiring separate wavelength management for different signal directions
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 reduces installation complexity and cost by enabling reliable, high-speed data transmission (greater than 1 Gbits/sec) in avionics systems with reduced fiber count, supporting large optical link margins and minimizing re-work in avionics networks.
Implementation Method 1
A 2x1 fusion coupler with low back reflection is integrated into the transceiver. The 2x1 fusion coupler has an input/output optical fiber, a detector optical subassembly fiber, and a laser optical subassembly fiber optically coupled to respective ports of the 2x1 fusion coupler.
Implementation Method 2
A pluggable single-wavelength bidirectional transceiver with integrated fusion coupler... A 2x1 fusion coupler with low back reflection is integrated into the transceiver
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An apparatus configured to function as a pluggable single-wavelength bidirectional transceiver in a switching network. The apparatus includes: a 2x1 fusion coupler; an input/output optical fiber, a detector optical subassembly (OSA) fiber and a laser OSA fiber all connected to the 2x1 fusion coupler; and a transceiver that includes a transceiver electronic circuit printed wiring board (PWB) and laser and detector OSAs electrically coupled to the transceiver electronic circuit PWB. The laser OSA includes a laser that is situated to transmit light to the laser OSA fiber, while the detector OSA includes a photodetector that is situated to receive light from the detector OSA fiber. The transceiver electronic circuit PWB also includes a multiplicity of transceiver input/output metal contacts arranged at one pluggable end of the PWB.