Dual-mode microwave coupler for orthogonal polarization isolation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing microwave communication systems face challenges in simultaneously transmitting orthogonal polarized signals without electrical interference, particularly in line-of-sight communication links where multiple radios need to share a common antenna while maintaining independent operation.

Innovation Solution

The use of dual-mode couplers with square cross-sectional waveguide sections and offset slot configurations allows for the simultaneous propagation and isolation of orthogonal modes, enabling multiple radios to operate at different polarizations without interference by coupling electromagnetic waves through a common antenna.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple radios are connected to a common antenna using single-mode couplers, then the antenna can serve multiple radios, but electrical interference occurs between orthogonal polarized signals

Engineering Contradiction:

Improveantenna sharing capabilityVSAvoidelectrical interference between signals

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The invention divides the coupling function into two separate dual-mode couplers, each handling one radio connection. This segmentation allows independent control and isolation of signal paths, preventing electrical interference between orthogonal polarized signals while maintaining the ability to share a common antenna.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The dual-mode coupler acts as an intermediary device between the radios and the common antenna. It provides mode isolation that prevents signal interference, enabling multiple radios to connect to the same antenna without electrical interference between orthogonal polarized signals.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If independent single-mode couplers are used for each radio, then polarization independence is achieved, but device complexity increases

Engineering Contradiction:

Improvepolarization independenceVSAvoidnumber of couplers required

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The dual-mode coupler is designed to handle multiple operational modes within a single device structure. Each coupler can process both orthogonal polarized signals while maintaining isolation, reducing the overall system complexity compared to using multiple single-mode couplers while preserving polarization independence.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If a rectangular waveguide is used at high frequencies, then orthogonal modes can be supported, but manufacturing precision requirements increase

Engineering Contradiction:

Improveorthogonal mode supportVSAvoidwaveguide dimensional tolerance

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The invention modifies the waveguide cross-sectional dimensions to create a square configuration rather than using a standard rectangular waveguide. This parameter change enables support for orthogonal modes at high frequencies while maintaining more relaxed manufacturing tolerances, as square waveguides are easier to manufacture with consistent precision.

Inventive Principle:

Principle #35Parameter changes

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 solution enables efficient, interference-free transmission and reception of microwave signals at orthogonal polarizations, allowing multiple radios to share an antenna while maintaining independent operation and high isolation between modes, thus enhancing the reliability and capacity of microwave communication systems.

Implementation Method 1

An electromagnetic wave in one of the waveguide sections excites the slots and thereby excites a corresponding electromagnetic wave in the other waveguide section

Methodology Applied

Scientific EffectElectromagnetic wave coupling: Electromagnetic Induction

Implementation Method 2

微波信号在各自的双模传输线中传播

Methodology Applied

Scientific EffectWaveguide propagation: Waveguide

Implementation Method 3

the opposing end of the second waveguide section is terminated by a microwave-absorbing element to prevent undesirable microwave reflections

Methodology Applied

Scientific EffectElectromagnetic wave absorption: Absorption (EM radiation)

Data Source

PatentUS8244287B2Radio and antenna system and dual-mode microwave coupler

Publication Date: 2012.08.14 TRANGO NETWORKS LLC

AI summary

A radio and antenna system has a first microwave radio, second microwave radio, a first antenna and a dual mode coupler that has a first dual mode transmission line extending between a first port and a third port and a second dual mode transmission line extending between a second port and a microwave absorbing termination. The first microwave radio is coupled to the first port. The second microwave radio is coupled to the second port. The antenna is coupled to the third port. The first dual mode transmission line is coupled to the second dual mode transmission line so that microwave signals in either of the first dual mode transmission line and the second dual mode transmission line propagates microwave signals in the other of the first dual mode transmission line and the second dual mode transmission line.