Ethernet Network System Common Mode Signal Cancellation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing Ethernet network systems suffer from performance degradation due to common mode signals generated by inner circuit operations, which interfere with differential mode signals and reduce the quality of network information transmission.
Innovation Solution
The Ethernet network system employs a configuration with staggered transmission and reception of network data signals across multiple channels, utilizing inductors to create phase reversals and cancellations of common mode signals, thereby suppressing unwanted frequency spectra and reducing noise in differential mode signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If data are transmitted via four channels at the same time in Gigabit Ethernet, then transmission speed and bandwidth are improved, but common mode signals are generated that decrease signal quality
Solution Approach 1:
The patent applies periodic action by transmitting data signals through four channels with staggered timing, where each channel transmits at different time intervals. This periodic staggering creates phase differences in the common mode signals generated by inner circuits and clock generators, allowing these signals to cancel each other out through destructive interference, thereby reducing electromagnetic radiation and improving signal quality while maintaining high transmission speed
Solution Approach 2:
The patent introduces asymmetry in the transmission timing of the four channels, where channels are deliberately offset from each other by specific time delays (e.g., quarter period intervals). This asymmetric timing arrangement breaks the symmetry that would otherwise cause constructive interference of common mode signals, transforming the harmful interference into canceling signals while preserving the full bandwidth capability
2Productivity
If four channels transmit simultaneously for full-duplex communication, then productivity is improved, but noise in differential mode signals increases
Solution Approach 1:
The patent implements periodic action with staggered transmission intervals across four channels, where each channel operates at slightly different time phases. This periodic staggering causes the common mode signals generated by simultaneous circuit operations to exhibit phase differences, enabling them to cancel each other through destructive interference, thereby reducing noise in differential mode signals while maintaining full-duplex communication efficiency
Solution Approach 2:
The patent converts the harmful common mode signals generated by simultaneous four-channel transmission into a beneficial cancellation mechanism. By deliberately introducing time delays that create specific phase relationships (e.g., quarter-period offsets), the patent causes the harmful common mode signals to interfere destructively with each other, transforming what would be noise into a signal-cleaning effect that improves overall transmission quality
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 cancels common mode signals, improving the performance and quality of network data signals by suppressing odd-numbered frequencies and reducing noise, thus enhancing the overall transmission quality.
Implementation Method 1
The primary first inductor has a first terminal and a second terminal, and the first terminal and the second terminal are electrically connected to the first transmission module so as to receive the first network data signal
Implementation Method 2
Delay time between the first network data signal and the second network data signal is a quarter of a system signal period, delay time between the second network data signal and the third network data signal is a quarter of the system signal period, and delay time between the third network data signal and the fourth network data signal is a quarter of the system signal period
Data Source
AI summary
An Ethernet network system and method for cancelling common mode signal is disclosed. The Ethernet network system, with a system frequency, utilizes the delay time point of transmitting data so as to suppress frequency spectrum generated by the Ethernet network system. In other words, delay time between a first network data signal and a second network data signal is quarter of a system signal period, delay time between the second network data signal and a third network data signal is quarter of a system signal period, and delay time between the third network data signal and a fourth network data signal is quarter of a system signal period, so as to cancel common mode signals of a first channel and a third channel and cancel common mode signals of a second channel and a fourth channel, wherein the system signal period is corresponding to the system frequency.