Segmented Inductive Antenna for Humid Environments
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional inductive antennas for radiofrequency transmissions in humid environments face challenges due to varying electrical permittivity, leading to unstable resonant circuits and degraded performance, particularly in applications where additional insulation or thickness is undesirable.
Innovation Solution
A thin inductive antenna design featuring a flexible substrate with planar conductive windings interrupted at regular intervals, forming resonant subassemblies that are interconnected to maintain resonant frequency and quality factor, and a matching circuit to compensate for capacitive variations, ensuring operation without additional insulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional inductive antennas are used in humid environments, then radiofrequency transmissions can be performed, but the resonant circuit becomes unstable and quality factor degrades due to varying electrical permittivity
Solution Approach 1:
The antenna winding is divided into multiple independent turns rather than a continuous winding. This segmentation creates discrete conductive elements that reduce the overall parasitic capacitance formed with the humid environment, thereby stabilizing the resonant circuit characteristics despite variations in electrical permittivity.
Solution Approach 2:
The patent transitions from a planar single-layer winding to a three-dimensional multi-layer winding structure. By stacking multiple layers with specific spacing and orientations, the design reduces parasitic capacitance to the environment while maintaining inductive characteristics, thus improving resonant stability in humid conditions.
2Object-affected harmful factors
If additional insulation is added to protect the antenna in humid environments, then the antenna becomes more protected, but the overall thickness increases significantly
Solution Approach 1:
The patent extracts and eliminates the need for additional insulating layers by designing the antenna winding itself to be inherently resistant to humidity effects. The segmented multi-layer structure reduces parasitic capacitance without requiring external insulation, thus maintaining thin profile while providing protection.
Solution Approach 2:
The antenna structure serves its own protective function through its segmented multi-layer design. The specific geometric configuration and spacing of the winding turns inherently reduce susceptibility to humidity effects, eliminating the need for separate protective insulation layers.
3Stability of the object's composition
If the antenna winding is made continuous, then the inductive characteristics are maintained, but parasitic capacitances increase significantly in humid environments
Solution Approach 1:
The continuous winding is segmented into multiple discrete turns distributed across several layers. This segmentation breaks up the continuous conductive path that would form large parasitic capacitances with the environment, while the multi-layer arrangement maintains the necessary inductive characteristics through mutual inductance between layers.
Solution Approach 2:
The patent moves from a two-dimensional planar winding to a three-dimensional multi-layer structure. By distributing turns across multiple layers with specific spacing, the design reduces the surface area exposed to the environment at any one level, thereby reducing parasitic capacitance while maintaining inductive performance through vertical coupling.
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 antenna maintains stable resonant characteristics and efficient energy recovery in humid environments, reducing the need for additional insulation and maintaining a thin profile, suitable for applications like pipe tracking and fresh product packaging.
Implementation Method 1
This resonant circuit captures the flux of the high-frequency magnetic field produced by the base station when it is subjected to this field
Implementation Method 2
The resonant circuits of the reader and the transponder are usually tuned to the same resonant frequency
Data Source
Figure 1~3
Figure 4~10
Figure 5~6
AI summary
The invention relates to an inductive antenna, comprising: a first planar conductive winding (42) on a first surface of a substrate, said first winding being cut off at regular intervals so as to form a series of pairs of first conductors (522, 524; 542, 546; 562, 564); and a second planar conductive winding (44) on a second surface of the substrate, said second winding being provided opposite the first winding and cut off in a direction vertically perpendicular to that of the cutoffs of the first winding so as to form a series of pairs of second conductors (526, 528; 546, 548; 66, 568). Each pair of first conductors defines a resonant subassembly with the pair of second conductors opposite thereto, wherein each of the two first conductors of a single subassembly are electrically connected to another first conductor of another subassembly or to a terminal (41, 43) of the antenna, the second conductors of adjacent pairs are not electrically connected to each other, and one end (5224, 244, 5424, 5444, 5624, 5644) of each first conductor is either electrically connected (523, 543, 563, 525, 545, 565) to one end (5284, 5264, 5484, 5464, 5684, 5664) of a second conductor of the subassembly in question or is not connected thereto, in which case the second conductors of the subassembly in question are electrically connected to one another.