Pseudolite Positioning via Dual-Signal Phase Difference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current positioning systems face challenges in providing precise and continuous location services indoors and outdoors, especially with limited infrastructure and compatibility with current mobile terminals, due to interference from obstacles and the need for complex hardware and synchronization.
Innovation Solution
A method using two signals emitted from distant generators at the same frequency, allowing for unambiguous phase difference measurements to determine the receiver's position with high precision, reducing sensitivity to signal propagation disturbances and eliminating the need for synchronization between transmitters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sensor networks are deployed for indoor positioning, then positioning precision is improved, but infrastructure complexity and deployment cost increase significantly
Solution Approach 1:
The patent copies the satellite signal structure to terrestrial transmitters, creating pseudolites that emit GPS-compatible signals. This allows existing GPS receivers in mobile terminals to be used without modification, achieving precise positioning indoors without requiring specialized sensor infrastructure. The copying principle enables the system to leverage proven GPS technology while adapting it to indoor environments.
2Loss of information
If optical systems with cameras are used for positioning, then positioning information is obtained, but computational complexity and user operation constraints increase
Solution Approach 1:
The patent replaces optical camera-based positioning with radio frequency signal-based positioning. Instead of using cameras to capture and process visual information computationally, the system uses pseudolites to transmit radio signals that can be processed by standard GPS receivers. This substitution dramatically reduces computational complexity and eliminates the need for user actions like taking photos.
3Measurement precision
If dual-antenna phase difference measurement is implemented, then angle of arrival precision is improved, but terminal hardware complexity increases
Solution Approach 1:
Instead of equipping the mobile terminal with dual antennas for phase difference measurement, the patent inverts the approach by placing dual-antenna systems at the fixed pseudolite transmitters. The pseudolites transmit signals with known phase relationships from their separated antennas, and the mobile terminal's single antenna receives these signals. This inversion transfers the hardware complexity from the mobile terminal to the fixed infrastructure, making the terminal simpler while maintaining high positioning precision.
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
Enables precise, decimetric or centimeter-level positioning with a reduced infrastructure, compatible with all current mobile terminals, and maintains continuity between indoor and outdoor environments without requiring complex hardware or synchronization.
Implementation Method 1
allowing for unambiguous phase difference measurements to determine the receiver's position with high precision
Implementation Method 2
A method using two signals emitted from distant generators at the same frequency
Data Source
Figure 1~2
Figure 3~5
Figure 6~7
AI summary
The present invention relates to a method for locating at least one receiver (2) in a positioning system (1). The system includes: at least two generators (PL1, PL2), each generator emitting, on a single carrier, at least two signals that each have a different code, and a receiver (2) configured to detect the signals emitted by the generators (PL1, PL2). In said method: the receiver (2) measures, for each generator (PL1, PL2), the phase difference (δφj) between both signals emitted by the generator (PLj), and at least one geometric size, representing the position (xr, yr) of the receiver (2) in relation to the generators (PL1, PL2), is calculated on the basis of said measurements of the phase difference (δφj) in order to locate the receiver (2) in the positioning system (1).