Optical Transmission System Frequency Band Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In communication systems using electromagnetic waves as carrier waves, the overlay of main and control signals can lead to noise in frequency bands not used for communication, deteriorating the signal-to-noise ratio (SNR) due to overlapping frequency bands.
Innovation Solution
A transmission system that generates a coherent wave with a main signal and a control signal, where the frequency bands of the main and control signals do not overlap, using a modulated wave generation unit and a modulation unit to modulate the intermediate wave, ensuring the main and control signals are separated in frequency bands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a signal mixer is used to overlay the main signal and control signal in the electrical signal state, then both signals can be transmitted together, but noise in frequency bands not used for communication deteriorates the signal to noise ratio (SNR)
Solution Approach 1:
The patent transitions from overlaying signals in the time domain (electrical signal state) to overlaying them in the frequency domain (optical signal state). By converting electrical signals to optical signals and using wavelength division multiplexing, the system achieves signal overlay in a different dimension (frequency/wavelength), which prevents noise from deteriorating SNR while maintaining transmission efficiency.
Solution Approach 2:
The patent replaces the signal mixer (electrical domain device) with a wavelength division multiplexer (optical domain device). This substitution changes the underlying mechanism from electrical signal processing to optical signal processing, eliminating the noise overlay problem that occurs in the electrical domain while preserving the ability to transmit multiple signals simultaneously.
2Reliability
If the frequency bands of main signal and control signal are separated, then noise overlap is prevented and SNR is improved, but the device complexity increases due to additional modulation units
Solution Approach 1:
The patent combines the main signal and control signal transmission into a single optical communication channel using wavelength division multiplexing. Instead of using separate channels or complex time-division multiplexing, the system merges both signals into one optical carrier with different wavelength components, achieving frequency band separation while simplifying the overall device structure.
Solution Approach 2:
The optical modulation unit is designed to handle both main signal and control signal modulation functions simultaneously. By making the modulation unit multi-functional, the patent avoids needing separate dedicated modulation units for each signal type, thereby reducing device complexity while maintaining the ability to separate frequency bands for improved SNR.
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 approach effectively suppresses the deterioration of the signal-to-noise ratio (SNR) in communication systems by preventing noise overlap between the main and control signals, enhancing communication quality.
Implementation Method 1
a main signal overlays a control signal in a state of an electrical signal, the electrical signal after overlaying is converted into an optical signal
Implementation Method 2
a modulation unit that modulates the intermediate wave with a signal in which a frequency component does not overlay the frequency spectrum of the coherent wave generated by the modulated wave generation unit
Data Source
AI summary
An aspect of the present disclosure is a transmission system including a modulated wave generation unit that generates an intermediate wave, which is a coherent wave in which a frequency component of either of two signals overlays a frequency spectrum, the two signals being a main signal indicating transmitted information to be transmitted and a control signal indicating management information, which is information on communication between a transmission source of the transmitted information and a communication destination of the transmission source, and a modulation unit that modulates the intermediate wave with a signal in which a frequency component does not overlay the frequency spectrum of the coherent wave generated by the modulated wave generation unit out of the two signals that are the main signal and the control signal. In the transmission system, a frequency band of the main signal and a frequency band of the control signal do not overlap each other.