Multi-frequency Antenna Coupling Structure for Interference Reduction

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Solution Overview

Problem

Existing multi-band antennas face interference issues due to low-frequency induced currents from electromagnetic waves, which affect the signal transmission of low-frequency units when the balun structure and radiation arm of high-frequency units act as equivalent monopole antennas.

Innovation Solution

Incorporating a coupling structure within the high-frequency units that transmits signals above a preset threshold while blocking signals below this threshold, preventing interference by ensuring the electromagnetic waves radiated by equivalent monopole antennas are always above the low-frequency unit's operating frequency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If the balun structure and radiation arm of the high-frequency unit form an equivalent monopole antenna, then the high-frequency unit can radiate electromagnetic waves effectively, but the equivalent monopole antenna generates low-frequency induced currents that interfere with the low-frequency unit's signal

Engineering Contradiction:
Improveradiation efficiency of high-frequency unitVSAvoidlow-frequency induced current interference
Core Design Contradiction:
PowerVSObject-generated harmful factors

Solution Approach 1:

The patent extracts and removes the harmful low-frequency induced current from the system by introducing a coupling structure that blocks low-frequency signals. The coupling structure is inserted between the balun structure and radiation arm, specifically extracting the low-frequency component that would otherwise interfere with the low-frequency unit while allowing high-frequency signals to pass through for effective radiation.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The coupling structure serves as an intermediary element between the balun structure and radiation arm. It mediates the signal transmission by selectively blocking low-frequency induced currents while allowing high-frequency signals to pass, thus preventing the interference problem without compromising the radiation efficiency of the high-frequency unit.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If the preset length value of the balun structure is close to a quarter of a wavelength of the low-frequency unit, then the high-frequency unit can operate at its designated frequency band, but the balun structure and radiation arm become equivalent to a monopole antenna operating at low frequency, causing interference

Engineering Contradiction:
Improveoperating frequency band matchingVSAvoidfrequency interference to low-frequency unit
Core Design Contradiction:
Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The coupling structure extracts the problematic low-frequency operation characteristic from the balun structure and radiation arm combination. By blocking low-frequency signals, it prevents the equivalent monopole antenna from operating at low frequencies, thereby eliminating the interference while maintaining the high-frequency operating characteristics.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The coupling structure introduces local frequency-selective properties to the connection between the balun structure and radiation arm. It creates a localized filtering effect that blocks low-frequency signals at this specific point in the circuit, while allowing high-frequency signals to pass through unaffected, thus resolving the frequency interference issue.

Inventive Principle:
Principle #3Local quality

3Object-generated harmful factors

If a coupling structure is added to block low-frequency signals, then interference to the low-frequency unit is reduced, but the device complexity increases

Engineering Contradiction:
Improveinterference to low-frequency unitVSAvoidstructure complexity of high-frequency unit
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The coupling structure acts as a compact intermediary component that provides frequency-selective blocking functionality. It is integrated into the existing balun structure and radiation arm connection, adding minimal structural complexity while effectively blocking low-frequency induced currents and preventing interference to the low-frequency unit.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 configuration effectively reduces interference from the equivalent monopole antenna to the low-frequency unit's signal, allowing normal operation without significant interference, and can even eliminate interference entirely.

Implementation Method 1

The coupling sub-structure 221 is configured to: transmit a signal whose frequency is higher than a preset threshold, and block a signal whose frequency is lower than the preset threshold

Methodology Applied
Scientific EffectFrequency selective filtering: Filter (electronic)

Implementation Method 2

The balun structure 21 is a device configured to implement a signal connection between the radiation arm structure of the antenna and a cable

Methodology Applied
Scientific EffectBalun transformation: Electromagnetic Induction

Implementation Method 3

The radiation arm structure is configured to radiate an electromagnetic wave to the outside

Methodology Applied
Scientific EffectElectromagnetic radiation: Electromagnetic Induction

Data Source

PatentEP3843211B1Multi-frequency antenna and communication device
Publication Date: 2023.07.05 HUAWEI TECH CO LTD
  • EP3843211B1 patent drawingFigure 1
  • EP3843211B1 patent drawingFigure 2~3
  • EP3843211B1 patent drawingFigure 4~5

AI summary

Embodiments of the present invention pertain to the field of communications technologies and disclose a multi-band antenna and a communications device. The multi-band antenna includes a reflection panel, at least one high-frequency unit, and at least one low-frequency unit. Each high-frequency unit includes a balun structure, a coupling structure, and a radiation arm structure. The balun structure includes two balun sub-structures, the coupling structure includes two coupling sub-structures, and the radiation arm structure includes two radiation arms. The high-frequency unit and the low-frequency unit are disposed on the reflection panel. Each coupling sub-structure is separately electrically connected to one balun sub-structure and one radiation arm. The coupling sub-structure is configured to: transmit a signal whose frequency is higher than a preset threshold, and block a signal whose frequency is lower than the preset threshold. According to the present invention, a frequency of an electromagnetic wave radiated by an equivalent monopole antenna to the outside is higher than a preset threshold due to existence of the coupling structure, thereby staggering from an operating frequency band of the low-frequency unit, so that the equivalent monopole antenna causes no interference to a signal radiated and transmitted by the low-frequency unit.