Single-LEO Doppler Positioning for Low-Energy IoT Localization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for locating ground-based devices using Low Earth Orbit (LEO) satellites are resource-intensive and lack precision, particularly for resource-constrained IoT devices.

Innovation Solution

A method utilizing Doppler measurements and machine learning models to iteratively refine the geographical search window, employing non-linear and linear regression techniques to enhance precision, allowing location with a single LEO satellite.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If multiple LEO satellites are used for ground-based device location, then measurement precision improves, but device complexity and resource requirements increase

Engineering Contradiction:
Improvelocation precisionVSAvoidsatellite constellation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts the location function from a multi-satellite constellation context and implements it using a single LEO satellite. By isolating the essential Doppler measurement mechanism and removing the requirement for multiple satellites, the system achieves location functionality with reduced complexity while maintaining acceptable precision through iterative refinement of the geographical window.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent dynamically adjusts the geographical window parameters (area and center position) across multiple iterations. The window area is reduced and repositioned based on previous estimation results, transforming the search space progressively. This parameter adaptation allows a single satellite to achieve precision comparable to or exceeding traditional multi-satellite systems.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If traditional multi-satellite constellations are used for IoT device location, then location accuracy improves, but energy consumption increases

Engineering Contradiction:
Improvelocation accuracyVSAvoidenergy consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent removes the energy-intensive multi-satellite infrastructure requirement and extracts the core location capability to a single satellite system. This extraction dramatically reduces the energy burden on ground-based IoT devices while preserving location accuracy through intelligent signal processing and iterative geographical window refinement.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent employs a simplified, single-satellite approach that can be deployed more economically and with lower energy requirements compared to maintaining large satellite constellations. The system uses readily available Doppler measurement techniques from a single passing satellite rather than requiring continuous coverage from multiple expensive satellites.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Measurement precision

If processing power is increased to improve location precision, then measurement precision improves, but device complexity and resource constraints are violated

Engineering Contradiction:
Improveposition estimation precisionVSAvoidprocessing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent performs preliminary actions by pre-defining and pre-processing the geographical window parameters before actual location calculation. The iterative refinement of the geographical window is prepared in advance, allowing the main processing to focus on Doppler measurement analysis rather than exhaustive search across the entire globe. This preliminary structuring reduces real-time processing demands.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamic adaptation of the geographical window parameters during the location process. The window area and center are adjusted based on intermediate results, allowing the system to concentrate processing power on the most relevant search regions. This dynamic focusing reduces the overall computational burden while improving precision in the final location estimate.

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

Achieves precise ground-based device location with a precision of around 1 kilometer using a single LEO satellite, reducing resource and energy requirements.

Implementation Method 1

Obtaining Doppler measurements corresponding to a plurality of signals transmitted at a predetermined frequency between the ground-based device and a non-geostationary satellite orbiting a celestial body

Methodology Applied
Scientific EffectDoppler effect: Doppler Effect

Data Source

PatentEP4657108A1Method for locating a ground-based device using one leo satellite and associated system
Publication Date: 2025.12.03 EUTELSAT
  • EP4657108A1 patent drawingFigure 1~2
  • EP4657108A1 patent drawingFigure 3~4
  • EP4657108A1 patent drawingFigure 5~6

AI summary

The invention concerns a method for locating a ground-based device (10) using only one non-geostationary satellite (20), wherein Doppler measurements are extracted from received signals, and a plurality of computing iterations are performed, each computing iteration comprising defining a new geographical window having an area different from an area of a directly preceding geographical window, simulating Doppler curves for a plurality of positions inside the defined geographical window, training a machine learning model with the simulated Doppler curves associated with their position of emission, and obtaining a location of the ground-based device (10) by inputting in the trained model the extracted Doppler measurements.