Multi-Antenna Radio Navigation Receiver with Signal Switching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Single-antenna receivers in satellite radio-navigation systems, such as those used in space launchers, face signal masking issues due to the vehicle's fuselage, leading to signal loss and suboptimal performance, and existing solutions do not adequately address temporary signal losses or optimize signal-to-noise ratios.

Innovation Solution

A device with a plurality of antennas arranged on the circumference of the fuselage, each with a dedicated reception chain including demodulation means, code and carrier loops, and interconnection mechanisms to switch between channels based on signal quality, ensuring continuous operation and optimal signal processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single antenna is used on the fuselage, then the device complexity is reduced, but signal reception reliability deteriorates due to masking by the fuselage body

Engineering Contradiction:
Improveantenna configurationVSAvoidsignal reception
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The single antenna is segmented into multiple antennas (at least two) distributed around the fuselage circumference. Each antenna serves as an independent reception element, ensuring that when one antenna is blocked by the fuselage, others remain accessible to satellite signals, thereby maintaining reliable signal reception while reducing overall system complexity compared to more elaborate antenna arrays.

Inventive Principle:
Principle #1Segmentation

2Reliability

If an annular antenna is used around the fuselage circumference, then signal reception reliability is improved by avoiding masking, but signal-to-noise ratio deteriorates due to non-optimal signal construction

Engineering Contradiction:
Improvesignal reception continuityVSAvoidsignal-to-noise ratio
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The annular antenna is segmented into multiple discrete antennas positioned around the fuselage. Each antenna produces an independent signal output that is processed separately through dedicated demodulation chains, allowing optimal signal construction from each element rather than combining signals from a single non-optimal annular structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The signal processing transitions from a single-dimension annular antenna output to multi-dimensional independent signal streams from multiple antennas. Each antenna's signal is demodulated and processed independently, adding spatial dimensionality to the signal reception and enabling selection of the best signal quality from multiple sources.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Reliability

If multiple antennas with separate demodulation chains are used, then signal reception reliability is improved by compensating for masking, but device complexity increases

Engineering Contradiction:
Improvesignal reception robustnessVSAvoidreception chain configuration
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The reception system is segmented into multiple independent reception chains, each handling signals from a specific antenna. This modular segmentation allows each chain to be optimized independently while maintaining overall system reliability through diversity, balancing the increased complexity with proportional gains in robustness.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system dynamically changes operational parameters by switching between different reception chains based on signal quality assessment. When one antenna experiences masking or signal loss, the system transitions to using signals from other antennas, adjusting the operational state to maintain optimal performance despite the multi-chain configuration.

Inventive Principle:
Principle #35Parameter changes

4Measurement precision

If signals from multiple antennas are combined, then signal-to-noise ratio is improved, but the system cannot handle temporary signal loss on individual antennas

Engineering Contradiction:
Improvesignal-to-noise ratioVSAvoidsignal loss compensation
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The signal processing system is made dynamic by implementing real-time monitoring and switching capabilities between multiple reception chains. Instead of static signal combining, the system actively assesses signal quality from each antenna and dynamically selects or switches between chains, enabling adaptation to temporary signal losses while maintaining optimal signal-to-noise ratio through selective signal utilization.

Inventive Principle:
Principle #15Dynamics

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 enhances performance by maintaining signal reception and optimizing signal-to-noise ratios, even when one antenna is masked, by exploiting diversity in demodulation channels and correcting for optical path differences, ensuring reliable navigation data.

Implementation Method 1

A GNSS receiver can be used on any type of vehicle to determine information about its position, its speed

Methodology Applied
Scientific EffectElectromagnetic radiation reception: Electromagnetic Induction

Implementation Method 2

demodulation means comprising multiplication means in phase with a local carrier

Methodology Applied
Scientific EffectPhase multiplication demodulation: Homodyne Detection

Implementation Method 3

time correlation means with a local code and means for integrating the correlated signal

Methodology Applied
Scientific EffectCode correlation:

Implementation Method 4

the carrier loop comprising a phase discriminator

Methodology Applied
Scientific EffectPhase discrimination:

Implementation Method 5

an NCO digital control operator capable of delivering a local carrier phase

Methodology Applied
Scientific EffectNumerical control oscillation:

Data Source

PatentEP2642317B1Device for receiving radio-navigation signals with multiple antennas
Publication Date: 2020.05.06 THALES SA
  • EP2642317B1 patent drawingFigure 1a~1b
  • EP2642317B1 patent drawingFigure 2

AI summary

The device has receiving channels (200, 300) comprising interconnection units (208, 308) for interconnecting inputs of a digital checking operator (226) of a loop. Each receiving channel operates to open the loop when the signal transmitted by a satellite is not received by an antenna. A selecting unit (400) selects a measurement time (T1) for delivering the signal by the receiving channel operative in a closed state of the loop, which presents the signal to noise ratio resulted from a highest reception antenna gain.