Chassis Slot Antenna Using PCB Resonator for Internal Signal Quality

Solution Overview

Problem

Wireless communication devices with metallic chassis require external antennas due to signal interference, leading to increased costs, complex installation, and poor aesthetics, as metal chassis interfere with communication signals if antennas are positioned internally.

Innovation Solution

A slot antenna is integrated into the metallic chassis using a printed circuit board with a conductive path extending between the board and the chassis, featuring a ground plane with a resonator and feed terminals, allowing the antenna to operate internally while avoiding interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If antennas are mounted externally on metal chassis, then signal interference is avoided, but device cost increases, installation becomes complicated, and aesthetics deteriorate

Engineering Contradiction:

Improvesignal qualityVSAvoidinstallation complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the antenna with the metal chassis by creating a slot antenna directly in the chassis structure. The slot antenna is formed by creating a slot in the metal chassis and positioning a printed circuit board with conductive elements against the interior surface, effectively combining the antenna function with the existing chassis structure rather than adding a separate external antenna component.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces a printed circuit board as an intermediary between the metal chassis and the antenna function. The PCB with its conductive layers and resonator structure acts as a mediator that enables internal antenna operation while maintaining signal quality by isolating the antenna elements from direct contact with the conductive chassis surface.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If antennas are mounted externally on metal chassis, then signal interference is avoided, but device cost increases

Engineering Contradiction:

Improvesignal qualityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent merges the antenna with the metal chassis by creating a slot antenna directly in the chassis structure. The slot antenna is formed by creating a slot in the metal chassis and positioning a printed circuit board with conductive elements against the interior surface, effectively combining the antenna function with the existing chassis structure rather than adding a separate external antenna component.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If antennas are mounted externally on metal chassis, then signal interference is avoided, but device aesthetics deteriorate

Engineering Contradiction:

Improvesignal qualityVSAvoiddevice aesthetics

Core Design Contradiction:

ReliabilityVSShape

Solution Approach 1:

The patent merges the antenna with the metal chassis by creating a slot antenna directly in the chassis structure. The slot antenna is formed by creating a slot in the metal chassis and positioning a printed circuit board with conductive elements against the interior surface, effectively combining the antenna function with the existing chassis structure rather than adding a separate external antenna component.

Inventive Principle:

Principle #5Merging (Combining)

4Volume of moving object

If antennas are positioned internally within metal chassis, then device becomes compact and aesthetic, but signal interference occurs

Engineering Contradiction:

Improvedevice compactnessVSAvoidsignal quality

Core Design Contradiction:

Volume of moving objectVSReliability

Solution Approach 1:

The patent introduces a printed circuit board as an intermediary between the metal chassis and the antenna function. The PCB with its conductive layers and resonator structure acts as a mediator that enables internal antenna operation while maintaining signal quality by isolating the antenna elements from direct contact with the conductive chassis surface.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent applies local quality by creating a specific slot configuration in the metal chassis and positioning PCB elements at specific locations. The slot dimensions, position, and the PCB conductive element placement are locally optimized to achieve resonant frequencies and maintain signal quality while keeping the antenna internal to the chassis structure.

Inventive Principle:

Principle #3Local 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

The solution enables wireless communication devices to send and receive signals internally, reducing costs, complexity, and bulkiness, while providing a compact and aesthetically pleasing design, and allows for flexible frequency tuning.

Implementation Method 1

The resonator in the conductive layer and the slot in the metallic chassis are configured to produce a resonant frequency when a radio frequency

Methodology Applied

Scientific EffectResonance: Resonance

Data Source

PatentEP4239799A1Chassis slot antenna

Publication Date: 2023.09.06 ROSEMOUNT AEROSPACE INC

Figure 1
Figure 2~3

AI summary

A wireless communication device includes a metallic chassis (18), a slot (20) extending through a sidewall of the metallic chassis, and a slot antenna (14) secured to an inner surface (19) of the metallic chassis and adjacent the slot. The slot antenna is integrated into the metallic chassis, giving the appearance and function of an internal antenna used with wireless communication devices having non-metallic chassis.