Doppler Radar Motion Compensation Using Integrated GNSS and IMU

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Solution Overview

Problem

Conventional remote sensing systems, such as radar and sonar, suffer from measurement errors due to motion, leading to inaccurate data and imagery, particularly in dynamic environments, which can compromise navigation and situational awareness for mobile structures.

Innovation Solution

A remote sensing imagery system incorporating radar assemblies with integrated orientation and position sensors (OPS) and a logic device to provide accurate Doppler radar imagery by directly measuring antenna orientation and velocity relative to an inertial frame, using a GNSS compass to correct for bias and drift, and employing a combination of GNSS and IMU to reduce errors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional remote sensing systems are used, then the system is simple and inexpensive, but measurement errors increase due to motion, reducing data reliability

Engineering Contradiction:
Improvedata reliabilityVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines multiple sensor types (GPS for position, compass for orientation, accelerometers for motion detection) into an integrated sensor system that works together to compensate for motion effects. This merging of sensors allows the system to maintain high data reliability while managing complexity through coordinated operation of the combined components.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces an intermediary processing system that receives raw sensor data from multiple sources, processes this data to calculate motion compensation parameters, and applies these corrections to the radar measurements. This intermediary layer isolates the complexity of motion compensation from both the raw sensors and the final imaging process.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If motion compensation techniques are applied, then measurement precision improves, but device complexity increases

Engineering Contradiction:
Improvevelocity measurement precisionVSAvoidprocessing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent performs preliminary calculations of motion compensation parameters using GPS and compass data before the radar imaging process. By pre-calculating the vessel's position, orientation, and velocity, the system prepares correction data in advance, which simplifies the actual imaging process and reduces real-time processing complexity while maintaining high measurement precision.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements a feedback mechanism where motion sensor data continuously updates the compensation parameters during the radar imaging process. The system monitors changes in vessel motion and dynamically adjusts the Doppler compensation accordingly, ensuring high velocity measurement precision without requiring overly complex fixed algorithms.

Inventive Principle:
Principle #23Feedback

3Reliability

If multiple sensors are integrated, then error reduction improves, but ease of operation decreases

Engineering Contradiction:
Improveerror reductionVSAvoidsystem operation simplicity
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent implements self-service functionality where the integrated sensor system automatically calibrates and compensates for motion effects without requiring manual intervention. The system autonomously processes sensor data, calculates compensation parameters, and applies corrections to radar images, eliminating the need for operators to manually adjust multiple sensor settings and reducing operational complexity despite the presence of multiple sensors.

Inventive Principle:
Principle #25Self-service

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 system provides highly accurate and reliable remote sensing data and imagery, reducing errors and enhancing navigation by directly measuring target radial velocity and compensating for motion-related inaccuracies, thereby improving situational awareness for mobile structures.

Implementation Method 1

A remote sensing imagery system may include radar assemblies, other remote sensing assemblies, and logic devices in communication with the various assemblies

Methodology Applied
Scientific EffectRadar: Radar

Implementation Method 2

using a GNSS compass to correct for bias and drift

Methodology Applied
Scientific EffectGNSS:

Implementation Method 3

employing a combination of GNSS and IMU to reduce errors

Methodology Applied
Scientific EffectIMU:

Implementation Method 4

determine a target radial speed corresponding to the detected target, and then generate remote sensor image data based on the remote sensor returns and the target radial speed

Methodology Applied
Scientific EffectDoppler effect: Doppler Effect

Data Source

PatentUS12392887B2Enhanced doppler radar systems and methods
Publication Date: 2025.08.19 RAYMARINE UK
  • US12392887B2 patent drawing
  • US12392887B2 patent drawing
  • US12392887B2 patent drawing

AI summary

Techniques are disclosed for systems and methods to provide remote sensing imagery for mobile structures. A remote sensing imagery system includes a radar assembly mounted to a mobile structure and a coupled logic device. The radar assembly includes an orientation and position sensor (OPS) coupled to or within the radar assembly and configured to provide orientation and position data associated with the radar assembly. The logic device is configured to receive radar returns corresponding to a detected target from the radar assembly and orientation and/or position data corresponding to the radar returns from the OPS, determine a target radial speed corresponding to the detected target, and then generate remote sensor image data based on the remote sensor returns and the target radial speed. Subsequent user input and/or the sensor data may be used to adjust a steering actuator, a propulsion system thrust, and/or other operational systems of the mobile structure.