Relay Vehicle Constellation for Multipath-Resilient Rover Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
GNSS positioning accuracy is compromised in multipath environments, such as urban canyons, due to signal reflections and obstructions, leading to poor precision and integrity of position, velocity, and time (PVT) calculations, even with advanced receivers.
Innovation Solution
A two-tier navigation system utilizing relay vehicles that retransmit GNSS-like signals to improve signal-to-noise ratio (SNR) and geometric dilution of precision (DOP) by positioning aerial or nautical relay vehicles to optimize the configuration and communication architecture, allowing for various communication media like RF, optical, or acoustic links, and using algorithms to compute navigation commands for optimal positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If advanced receivers with multiple correlators and processing techniques are used, then signal processing quality improves, but the number of visible satellites and geometric dilution of precision remain poor in multipath environments
Solution Approach 1:
The patent introduces relay vehicles as intermediary nodes between GNSS satellites and ground-based receivers. These relay vehicles receive direct GNSS signals in space or upper atmosphere where multipath effects are minimal, then retransmit processed positioning signals to ground receivers, thereby mediating the signal transmission to bypass multipath interference from urban canyons and other obstructive environments
Solution Approach 2:
The patent transitions the signal reception from the ground level (2D surface) to the aerial or nautical dimension (3D space). By positioning relay vehicles in the air or on water surfaces, the system exploits the additional vertical dimension to achieve direct line-of-sight to satellites that are blocked from ground-based receivers, fundamentally changing the geometric relationship between receiver and satellites
2Measurement precision
If relay vehicles are deployed to improve positioning signals, then positioning accuracy in challenging environments improves, but system complexity and cost increase
Solution Approach 1:
The patent implements dynamic positioning and configuration of relay vehicles that can adapt their positions and signal transmission parameters in real-time based on the spatial distribution of receivers and current GNSS signal conditions. This dynamic approach allows the system to optimize positioning accuracy without requiring a fixed, overly complex constellation configuration
Solution Approach 2:
The system changes key parameters such as relay vehicle altitude, horizontal position, and signal transmission power to optimize the balance between positioning accuracy and system complexity. By adjusting these parameters dynamically, the system achieves improved PVT accuracy without requiring excessive relay vehicles or complex configurations
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
Enhances PVT accuracy and integrity by increasing SNR and reducing DOP, enabling reliable navigation in challenging environments, including urban areas and underwater operations, with potential cost savings by optimizing the relay vehicle constellation.
Implementation Method 1
transmitting signals to a rover positioned on a surface... using various communication media like RF, optical, or acoustic links
Data Source
Figure 1
Figure 2a~2b
Figure 3a~3b
AI summary
The invention discloses a constellation of relay vehicles comprising a receiver of navigation signals and a transmitter of positioning signals to an area of service where a number of rovers manoeuver, wherein the position of the relay vehicle may be adjusted to optimize one or more of an SNR or a DOP index of the positioning signals. In some embodiments, the optimal configuration of the constellation of relay vehicles may be further defined based on priority indexes allocated to the rovers. The invention is applicable to terrestrial or underwater rovers, respectively serviced by aerial or nautical relay vehicles.