Bidirectional Transmission Line with Common Mode Voltage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bidirectional data transmission systems face challenges with frequent direction switching, leading to signal reflections, electromagnetic interference (EMI), and high power consumption due to the need for large low-resistance switches and infrequent impedance matching.
Innovation Solution
A system utilizing common mode voltage circuitry for rapid direction switching on a transmission line with differential signal generation and current injection, combined with resistances for impedance matching, allowing for efficient bidirectional communication without EMI and reduced power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If large low-resistance switches are used for direction switching, then direction switching capability is improved, but power consumption increases and EMI emissions occur
Solution Approach 1:
The patent changes the resistance parameter dynamically by using high-impedance switches instead of low-resistance switches. The switches transition between high-impedance states for direction control, eliminating the need for large current switching while maintaining direction switching capability. This parameter change reduces power consumption and EMI emissions.
Solution Approach 2:
The patent replaces the mechanical/electrical switching system with a field-based impedance control system. Instead of using physical switches that conduct large currents, the system uses impedance matching and common-mode voltage control to achieve direction switching, substituting a field-based control mechanism for traditional electrical switching.
2Productivity
If direction switching is performed frequently, then communication efficiency is improved, but signal reflections and EMI emissions increase
Solution Approach 1:
The patent maintains equipotential conditions on the transmission line by controlling the common-mode voltage. The common-mode voltage circuitry ensures that both signal lines remain at a stable reference potential during direction switching, preventing potential differences that would cause signal reflections and EMI emissions while enabling frequent direction changes.
Solution Approach 2:
The patent implements feedback control through the common-mode voltage circuitry that continuously monitors and adjusts the voltage levels on the transmission line. This feedback mechanism detects changes in transmission direction and actively maintains proper voltage levels to prevent reflections and EMI, enabling stable frequent direction switching.
3Device complexity
If impedance matching is not maintained, then device complexity is reduced, but signal reflections increase
Solution Approach 1:
The patent integrates multiple functions into the common-mode voltage circuitry, which simultaneously performs impedance matching, direction control, and reflection prevention. This universal circuit element handles what would otherwise require separate dedicated components, maintaining impedance matching without significantly increasing overall device complexity.
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
Enables rapid direction switching with minimized EMI and power consumption, effectively counteracting signal reflections while maintaining compatibility with legacy connector configurations.
Implementation Method 1
a first module includes common mode voltage circuitry, for imposing a common mode voltage onto the first and second wires
Implementation Method 2
signal generation circuitry, for generating a signal voltage in response to first data, and for imposing the signal voltage as a differential signal onto the first and second wires
Implementation Method 3
current generation circuitry, for generating a signal current in response to second data, and for injecting the signal current as a differential current onto the first and second wires
Implementation Method 4
the first module includes respective resistances connected to the first and second wires
Implementation Method 5
the first module includes a first detector for obtaining first output data based on voltages across the resistors resulting from the signal current injected by the current generation circuitry of the second module
Data Source
AI summary
A system comprises a first module and a second module, connected by a transmission line comprising first and second wires. The first module includes common mode voltage circuitry, for imposing a common mode voltage onto the first and second wires. The first module includes signal generation circuitry, for generating a signal voltage in response to first data, and for imposing the signal voltage as a differential signal onto the first and second wires during periods when the first module has first data to transmit. The second module includes current generation circuitry, for generating a signal current in response to second data, and for injecting the signal current as a differential current onto the first and second wires during periods when the second module has second data to transmit. The first module includes respective resistances connected to the first and second wires. The first module includes a first detector for obtaining first output data based on voltages across the resistors resulting from the signal current injected by the current generation circuitry of the second module; and the second module includes a second detector for obtaining second output data based on differential signal imposed by the signal generation circuitry of the first module.