Reflector Feed Polarization Predistortion for Mismatch Mitigation

Solution Overview

Problem

Reflector antenna systems often suffer from polarization mismatch due to design limitations, particularly in center-fed systems causing shadow effects and offset-fed systems experiencing increased cross-polarization at oblique incident angles, leading to reduced efficiency and distorted polarization.

Innovation Solution

A method and apparatus that pre-distort the polarization of the wave generated by the feed unit to compensate for polarization mismatch between the feed and reflector units, using techniques such as orthogonal pins or dielectric slabs within the feed unit to adjust the polarization of the input wave before illumination, thereby reducing or eliminating polarization mismatch and enhancing signal strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If offset-fed configuration is used to avoid shadow effects and increase gain, then antenna efficiency is improved, but cross-polarization increases at oblique incident angles causing polarization mismatch

Engineering Contradiction:

Improveantenna efficiencyVSAvoidpolarization matching

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by pre-distorting the polarization of the input wave before it reaches the reflector. The feed unit modifies the polarization state in advance to compensate for the expected polarization mismatch that will occur after reflection, thereby maintaining polarization alignment despite the oblique incident angle

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the polarization parameters of the input wave by applying pre-distortion techniques. The feed unit adjusts polarization parameters such as axial ratio and polarization angle to compensate for the degradation that occurs during oblique reflection, transforming the wave characteristics to achieve better matching

Inventive Principle:

Principle #35Parameter changes

2Device complexity

If center-fed configuration is used to simplify feed structure, then device complexity is reduced, but shadow effects occur on the reflector unit reducing received power

Engineering Contradiction:

Improvefeed structure complexityVSAvoidreceived power

Core Design Contradiction:

Device complexityVSLoss of energy

Solution Approach 1:

The patent applies preliminary action by pre-distorting the polarization of the input wave before it reaches the reflector. The feed unit modifies the polarization state in advance to compensate for the expected polarization mismatch that will occur after reflection, thereby maintaining polarization alignment despite the oblique incident angle

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the polarization parameters of the input wave by applying pre-distortion techniques. The feed unit adjusts polarization parameters such as axial ratio and polarization angle to compensate for the degradation that occurs during oblique reflection, transforming the wave characteristics to achieve better matching

Inventive Principle:

Principle #35Parameter changes

3Reliability

If reflector unit is designed to minimize cross-polarization, then polarization matching is improved, but adjustments cannot be made after deployment reducing system adaptability

Engineering Contradiction:

Improvepolarization matchingVSAvoidsystem adjustability

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent applies preliminary action by pre-distorting the polarization of the input wave before it reaches the reflector. The feed unit modifies the polarization state in advance to compensate for the expected polarization mismatch that will occur after reflection, thereby maintaining polarization alignment despite the oblique incident angle

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the polarization parameters of the input wave by applying pre-distortion techniques. The feed unit adjusts polarization parameters such as axial ratio and polarization angle to compensate for the degradation that occurs during oblique reflection, transforming the wave characteristics to achieve better matching

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

The pre-distortion technique effectively reduces or eliminates polarization mismatch, increasing the signal strength of the re-radiated wave and improving overall antenna efficiency by aligning the polarization of the re-radiated wave with the input wave, thus enhancing the performance of reflector antenna systems.

Implementation Method 1

pre-distort the first wave to achieve a compensated polarization for reducing and/or eliminating a polarization mismatch

Methodology Applied

Scientific EffectPolarization pre-distortion: Polarisation

Implementation Method 2

a reflector unit for receiving the pre-distorted first wave and reflecting at least a re-radiated wave

Methodology Applied

Scientific EffectElectromagnetic reflection: Reflection

Data Source

PatentUS11804658B2Mitigation of polarization mismatch between reflector and feed antennas by feed predistortion

Publication Date: 2023.10.31 HUGHES NETWORK SYST

AI summary

An apparatus and method for mitigating polarization mismatch in reflector antenna systems. A feed unit is configured to determine a polarization mismatch between a first polarization associated with a first wave and a second polarization associated with a reflector unit. The feed unit pre-distorts the first wave to achieve a compensated polarization for reducing and/or eliminating a polarization mismatch. The pre-distorted first wave having the compensated polarization is used to illuminate the reflector unit. A re-radiated wave is reflected by the reflector unit. Furthermore, the level of the re-radiated wave is increased as a result of the pre-distortion.