Differential Cable Ground Layout for High-Frequency Crosstalk Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing high-frequency signal transmission cables face challenges in further enhancing isolation between differential transmission lines to suppress crosstalk and electromagnetic noise, particularly when ground lines or GND planes are shared by adjacent differential transmission lines.
Innovation Solution
A high-frequency signal transmission cable design featuring first and second wiring layers with non-overlapping allocation of ground lines to differential transmission lines, where each differential transmission line is interposed between at least two first ground lines and opposed to at least one second ground line, with electrical coupling via interlayer-wirings, and connectors with non-overlapping ground contact terminals to enhance electrical isolation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If ground lines or GND planes are shared by adjacent differential transmission lines, then device complexity is reduced and manufacturing is easier, but crosstalk and electromagnetic noise increase
Solution Approach 1:
The patent divides the ground lines into separate dedicated ground lines for each differential transmission line, rather than using shared ground lines or GND planes. This segmentation isolates the ground paths, preventing electromagnetic coupling between adjacent differential lines and reducing crosstalk, while still maintaining manufacturability through systematic arrangement.
Solution Approach 2:
The patent implements different ground line allocation strategies for different locations: dedicated ground lines are used adjacent to each differential transmission line to minimize crosstalk, while the overall structure maintains regular patterning for ease of manufacture. This local differentiation optimizes both isolation and manufacturability.
2Device complexity
If ground lines are shared by adjacent differential transmission lines, then device complexity is reduced, but electromagnetic noise increases
Solution Approach 1:
The patent segments the ground line configuration into dedicated ground lines for each differential transmission line. This segmentation prevents electromagnetic noise from coupling between adjacent lines by providing isolated ground paths, while the systematic arrangement keeps the overall device complexity manageable.
3Object-affected harmful factors
If dedicated ground lines are allocated to each differential transmission line, then crosstalk is reduced, but device complexity increases
Solution Approach 1:
The patent segments ground lines into dedicated assignments for each differential transmission line, with each differential line having its own dedicated ground lines. This segmentation effectively reduces crosstalk by isolating electromagnetic fields, while the regular, systematic arrangement of these segmented elements keeps the overall device complexity controlled.
Solution Approach 2:
The patent creates a universal ground line allocation pattern that can be applied consistently across multiple differential transmission lines. This standardized approach allows the dedicated ground line configuration to be implemented efficiently across the entire device, reducing the complexity burden that would otherwise arise from custom configurations for each line.
4Ease of manufacture
If shared GND plane is used, then manufacturing is easier, but signal integrity deteriorates due to ground potential sharing
Solution Approach 1:
The patent segments the continuous GND plane into separate, dedicated ground lines for each differential transmission line. This segmentation prevents ground potential sharing between adjacent lines, thereby improving signal integrity and reducing electromagnetic coupling, while the systematic arrangement of these segmented ground lines maintains ease of manufacturing through regular patterning.
Data Source
AI summary
High-frequency signal transmission cable includes: a dielectric layer; and first and second wiring layers arranged to sandwich the dielectric layer. The first wiring layer includes at least M (M indicating a natural number of 2 or more) differential transmission lines. The first wiring layer further includes a group of first ground lines including at least 2×M first ground lines. The second wiring layer includes a group of second ground lines including at least M second ground lines. The group of first ground lines are allocated to the M differential transmission lines in accordance with a condition of at least two first ground lines per one differential transmission line in non-overlap manner, and the group of second ground lines are allocated to the M differential transmission lines in accordance with a condition of at least one second ground line per one differential transmission line in non-overlap manner. Each of the differential transmission lines is interposed between the at least two first ground lines and is opposed to the at least one second ground line.