Bidirectional Optical Transceiver With O-Band Wavelength Multiplexing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bidirectional optical communication systems face challenges in increasing transmission capacity and reducing chromatic dispersion penalties, especially at high transmission rates like 100 Gb/s, due to limited wavelength bands and the need for complex compensation techniques.
Innovation Solution
A multichannel bidirectional optical transceiver using a zigzag glass block and thin-film filters to multiplex and demultiplex optical signals with different wavelengths, mitigating chromatic dispersion by employing a compact wavelength band near the zero-dispersion window of optical fibers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the transmission rate per wavelength is increased to 100 Gb/s, then the transmission capacity is improved, but the transmission penalty by chromatic dispersion increases significantly
Solution Approach 1:
The patent changes the wavelength parameter from conventional bands (C-band, L-band) to the O-band (1260-1360 nm), specifically utilizing wavelengths around 1310 nm where the zero-dispersion wavelength of standard single-mode fiber occurs. This parameter change exploits the physical property that chromatic dispersion is minimized at the zero-dispersion wavelength, thereby enabling 100 Gb/s transmission over 40 km without significant transmission penalty
2Device complexity
If wavelength division multiplexing is used for bidirectional transmission, then the number of optical fibers is reduced, but the available wavelength band is limited
Solution Approach 1:
The patent transitions from using multiple spatial dimensions (separate fibers for upstream and downstream) to utilizing the spectral dimension (wavelength multiplexing) within a single fiber. By employing the O-band for bidirectional wavelength division multiplexing, the system accommodates multiple wavelengths (e.g., 1310 nm and 1320 nm) within the same fiber, effectively expanding the usable wavelength space while maintaining single-fiber operation
3Ease of operation
If an optical filter is used to implement BOSA, then bidirectional transmission is enabled, but the wavelength spacing between upstream and downstream signals must be equal to or greater than a certain range
Solution Approach 1:
The patent applies local quality by utilizing the specific property of the O-band region where chromatic dispersion is naturally low. By concentrating both upstream and downstream wavelengths within this localized spectral region (1260-1360 nm), the system achieves fine wavelength spacing (e.g., 10 nm spacing between 1310 nm and 1320 nm) without requiring complex dispersion compensation, thereby relaxing the wavelength spacing constraint compared to conventional bands
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
Enhances transmission capacity and distance without complex compensation techniques, reducing chromatic dispersion impacts while maintaining high transmission rates over a single optical fiber.
Implementation Method 1
a wavelength division multiplexing method, which uses different wavelengths for downstream optical signals and upstream optical signals, respectively
Implementation Method 2
multiple filters disposed on the first side surface of the zigzag block, each of the multiple filters transmitting only an optical signal with a corresponding wavelength and reflecting optical signals with other wavelengths
Implementation Method 3
a mirror plane disposed on the second side surface of the zigzag block and configured to reflect an optical signal
Implementation Method 4
the transmission penalty by chromatic dispersion can no longer be ignored even in the O-band
Implementation Method 5
transmitting a 100 Gb/s PAM4 optical signal over 40 km
Data Source
AI summary
Disclosed herein is a multichannel bidirectional optical transceiver. The multichannel bidirectional optical transceiver may include a transmission unit for transmitting optical signals with two or more different wavelengths, a reception unit for receiving optical signals with two or more different wavelengths, and an optical filter block for multiplexing two or more optical signals transmitted by the transmission unit and outputting the same to a single optical fiber and for demultiplexing two or more optical signals received from the single optical fiber and inputting the same to the reception unit.