Waveguide Slot Antenna Surface Structure for Multiple Reflection Suppression

Solution Overview

Problem

Waveguide slot antennas experience multiple reflections between the antenna body and objects in the radiation direction, leading to performance degradation in radar and communication devices due to unwanted noise components and narrowed frequency bands.

Innovation Solution

The waveguide slot antenna incorporates a radiating section with slots spaced apart by a predefined distance and an outer wall surface featuring a periodic concave-convex pattern or rectilinear ridges and grooves to reflect incident waves in a different direction, preventing multiple reflections without the need for a frequency selection surface unit.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a frequency selection surface unit is arranged forward of the waveguide slot antenna to suppress multiple reflections, then the radar and communication performance is improved, but the device complexity and manufacturing cost increase

Engineering Contradiction:

Improveradar and communication performanceVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts and removes the frequency selection surface unit from the antenna system, eliminating the need for this separate component while maintaining the multiple reflection suppression function through the waveguide structure itself. This resolves the contradiction by achieving the desired performance improvement without adding device complexity.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention merges the multiple reflection suppression function into the waveguide slot antenna structure itself, specifically through the interaction between the radiating section and the object in the radiation direction. This integration eliminates the need for a separate frequency selection surface unit, thereby reducing device complexity while maintaining reliability.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If a frequency selection surface unit is arranged forward of the waveguide slot antenna to suppress multiple reflections, then the radar and communication performance is improved, but the manufacturing cost increases

Engineering Contradiction:

Improveradar and communication performanceVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The invention extracts and removes the frequency selection surface unit from the antenna system, eliminating the need for this separate component while maintaining the multiple reflection suppression function through the waveguide structure itself. This resolves the contradiction by achieving the desired performance improvement without adding manufacturing cost.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention merges the multiple reflection suppression function into the waveguide slot antenna structure itself, specifically through the interaction between the radiating section and the object in the radiation direction. This integration eliminates the need for a separate frequency selection surface unit, thereby reducing manufacturing cost while maintaining reliability.

Inventive Principle:

Principle #5Merging (Combining)

3Productivity

If the waveguide slot antenna transmits radio waves toward objects, then the communication function is achieved, but multiple reflections occur between the antenna and objects causing performance degradation

Engineering Contradiction:

Improvecommunication functionVSAvoidmultiple reflections

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The invention converts the harmful multiple reflections into a beneficial effect by utilizing the interaction between the radiating section and the object in the radiation direction to suppress the unwanted reflections. The radio waves that would normally cause harmful multiple reflections are instead used to achieve the suppression effect, thereby maintaining communication function while eliminating performance degradation.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 suppresses multiple reflections, maintains the frequency band and transmission/reception power, and enhances detection and communication accuracy by reducing unnecessary signal components.

Implementation Method 1

The uneven section is configured to reflect incident waves incident from forward in a direction of radiation of radio waves emitted from the radiating section, in a direction different from an incident direction of the incident waves

Methodology Applied

Scientific EffectReflection: Reflection

Data Source

PatentUS12597710B2Waveguide slot antenna

Publication Date: 2026.04.07 DENSO CORP

AI summary

A waveguide slot antenna includes a waveguide having a plurality of slots spaced apart by a predefined distance in a central-axis direction of the waveguide, as a radiating section. An uneven section provided on an outer wall surface around the radiating section has a periodic concave-convex pattern extending from the radiating section. The uneven section includes a plurality of protrusions spaced apart by a predefined distance in a dispersed manner in each of an axis direction parallel to the central-axis of the waveguide in which the plurality of slots are arranged and an axis direction orthogonal to the central-axis of the waveguide, and grooves between the protrusions. The plurality of protrusions and the grooves causes incident waves incident from forward in a direction of radiation of radio waves emitted from the radiating section to be reflected in a direction different from an incident direction of the incident waves.