Multilayer Filter Resonator Layout for Compact Band-Pass Coupling

Solution Overview

Problem

Existing band-pass filters face challenges in miniaturization due to structural and characteristic restrictions when using resonators with strong electromagnetic coupling, making it difficult to achieve desired characteristics in small-sized communication devices.

Innovation Solution

A multilayered filter device is designed with a combination of parallel and serial resonators, where parallel resonators have conductor structures wound orthogonal to the stacking direction and serial resonators have conductor layers wound parallel to the stacking direction, integrated within a stack of dielectric layers, allowing for reduced size while maintaining desired characteristics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If wound conductor layer resonators are used to achieve high inductance, then the filter can be miniaturized, but the electromagnetic coupling between resonators becomes too strong to obtain desired characteristics

Engineering Contradiction:

Improvefilter sizeVSAvoidelectromagnetic coupling characteristic

Core Design Contradiction:

Volume of moving objectVSReliability

Solution Approach 1:

The invention divides the resonators into two distinct types: wound conductor layer resonators (for high inductance and miniaturization) and non-wound resonators (for controlled electromagnetic coupling). This segmentation allows each type to fulfill its specific function without the negative effects overwhelming the system.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the filter are assigned different resonator types based on their functional requirements. High-inductance regions use wound resonators for miniaturization, while regions requiring controlled coupling use non-wound resonators. This local differentiation optimizes both size and characteristic performance.

Inventive Principle:

Principle #3Local quality

2Reliability

If all resonators are composed of conductor layer type or conductor structure type resonators, then high inductance is achieved, but miniaturization is difficult due to structural restriction

Engineering Contradiction:

ImproveinductanceVSAvoidfilter size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The invention merges two different resonator architectures (wound and non-wound) into a single filter system. This combination allows the filter to achieve the high inductance needed for performance while utilizing the space-efficient characteristics of both types to reduce overall size.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The filter employs a composite structure combining different resonator types with distinct electromagnetic properties. The wound resonators provide high inductance density, while the non-wound resonators provide controlled coupling characteristics, creating a composite system that overcomes the limitations of using a single resonator type.

Inventive Principle:

Principle #40Composite materials

3Reliability

If all resonators are composed of conductor layer type or conductor structure type resonators, then high inductance is achieved, but miniaturization is difficult due to characteristic restriction

Engineering Contradiction:

ImproveinductanceVSAvoidfilter size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The invention divides the resonators into two distinct types: wound conductor layer resonators (for high inductance and miniaturization) and non-wound resonators (for controlled electromagnetic coupling). This segmentation allows each type to fulfill its specific function without the negative effects overwhelming the system.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the filter are assigned different resonator types based on their functional requirements. High-inductance regions use wound resonators for miniaturization, while regions requiring controlled coupling use non-wound resonators. This local differentiation optimizes both size and characteristic performance.

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 design achieves miniaturization of band-pass filters while preserving desired electromagnetic properties, enabling effective performance in compact communication devices.

Implementation Method 1

a band-pass filter including a plurality of resonators

Methodology Applied

Scientific EffectElectromagnetic resonance: Resonance

Implementation Method 2

the electromagnetic coupling between the resonators is too strong

Methodology Applied

Scientific EffectElectromagnetic coupling: Electromagnetic Induction

Data Source

PatentUS12587156B2Multilayered filter device

Publication Date: 2026.03.24 TDK CORP

AI summary

A filter device includes a plurality of resonators and a stack. The plurality of resonators include a first parallel resonator and a first serial resonator. The first parallel resonator includes a conductor structure wound around an axis extending in a direction orthogonal to a stacking direction. The first serial resonator includes a conductor layer wound around an axis extending in a direction parallel to the stacking direction. The conductor layer includes three portions each located between a corresponding one of three side surfaces and at least part of the conductor structure when seen in the stacking direction.