Directional Coupler Signal Transformation Noise Immunity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Directional couplers used for signal transmission suffer from low noise immunity and signal amplitude attenuation, similar to single end signal transmission, limiting their effectiveness compared to differential signal transmission, and conventional connectors face reliability issues due to mechanical attachment.
Innovation Solution
A directional coupler design with a first transmission line having a matched termination and two electromagnetically coupled transmission lines, where the near and far ends of these lines are terminated with specific impedances to facilitate transformation between single end and differential signals, enhancing noise immunity and reliability through electromagnetic coupling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a directional coupler is used for signal transmission, then the signal can be transmitted without physical contact (improving reliability), but the signal amplitude strongly attenuates and noise immunity remains low (worsening signal quality)
Solution Approach 1:
The patent replaces mechanical contact-based connectors with a non-contact electromagnetic coupling system using a directional coupler. This substitution eliminates mechanical wear and contact reliability issues while maintaining signal transmission capability through electromagnetic fields between transmission lines.
Solution Approach 2:
The patent transforms the signal transmission mode by changing the termination impedance parameters of the coupled transmission lines. By optimizing the termination impedances and coupling coefficients, the system achieves both low signal attenuation and high noise immunity, resolving the contradiction between contactless transmission and signal quality.
2Object-affected harmful factors
If differential signal transmission is used, then noise immunity is high, but the amount of signal line required is two times that of single end signal transmission (increasing complexity)
Solution Approach 1:
The directional coupler serves multiple functions: it enables differential signal generation from single-end signals, provides impedance transformation, and achieves noise immunity. This multi-functionality allows the system to obtain differential signal benefits without requiring separate dedicated differential line pairs, reducing overall system complexity.
Solution Approach 2:
The directional coupler acts as an intermediary device that converts single-end signals into differential signals. This mediator enables the transmission line to achieve noise immunity characteristics of differential signaling while maintaining compatibility with single-end signal sources and reducing the need for separate differential line infrastructure.
3Device complexity
If single end signal transmission is used, then the amount of signal line is reduced, but noise immunity is low and signal amplitude attenuates
Solution Approach 1:
The patent changes the termination impedance parameters of the directional coupler to transform single-end signals into differential signals. By adjusting the termination impedances to specific values, the system achieves high noise immunity while maintaining single-end signal transmission infrastructure, thus improving signal quality without increasing line complexity.
4Ease of operation
If conventional connectors with mechanical attachment are used, then electrical connection is achieved, but reliability problems occur due to mechanical wear and contact issues
Solution Approach 1:
The patent eliminates mechanical connectors by using electromagnetic coupling between transmission lines. The electrical connection is achieved through magnetic and electric field coupling rather than physical contact, thereby eliminating mechanical wear, oxidation, and contact resistance issues while maintaining ease of electrical connection.
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 proposed directional coupler effectively transforms single end signals into differential signals and vice versa, improving noise immunity and reducing signal attenuation, while eliminating the need for physical contact in connectors, thus enhancing communication reliability and efficiency.
Implementation Method 1
a second transmission line electromagnetically coupled with the first transmission line; and a third transmission line electromagnetically coupled with the first transmission line
Data Source
AI summary
A directional coupler including a first transmission line including a terminal part provided with a matched termination, and a front end part being an end portion on a side opposite to a side of the terminal part; a second transmission line electromagnetically coupled with the first transmission line; and a third transmission line electromagnetically coupled with the first transmission line, wherein each of the second and third transmission lines includes a near end and a far end, the near end being positioned on a side closer to the front end part when tracing the first transmission line from the front end part, the far end being positioned on a side farther from the front end part when tracing the first transmission line from the front end part, and wherein the near end is terminated to have an impedance smaller than a characteristic impedance of the second transmission line.