GNSS Peak Tracking for Direct and Reflected Signals in Multipath
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional GNSS receivers in multipath environments produce biased measurements due to multipath signals, leading to poor accuracy in navigation solutions, as they typically provide only a single set of measurements without distinguishing between direct and reflected satellite signals.
Innovation Solution
A semiconductor package within a user device identifies multiple signal peaks within a tracking aperture and determines peak parameter estimates for both direct and reflected satellite signals, using a three-level iteration loop to generate and refine signal parameters, enabling the position engine to calculate a more accurate navigation solution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional GNSS receivers use a single tracking channel to provide measurements, then the device complexity is reduced, but the measurement precision deteriorates due to inability to distinguish direct and reflected signals
Solution Approach 1:
The patent divides the tracking process into multiple independent tracking channels (e.g., first tracking channel, second tracking channel, third tracking channel), each capable of independently acquiring and tracking satellite signals. This segmentation allows the receiver to distinguish between direct and reflected signals by processing them through separate channels, thereby improving measurement precision while managing device complexity through modular architecture
Solution Approach 2:
The patent introduces an additional dimension of signal analysis by implementing multiple tracking channels that operate in parallel, effectively adding a channel dimension to the traditional single-channel approach. This enables the system to resolve signal ambiguity by comparing measurements across multiple channels, improving precision without proportionally increasing complexity
2Reliability
If the receiver processes multiple signal peaks from multiple tracking channels, then the reliability of navigation solution improves, but the device complexity increases due to additional processing requirements
Solution Approach 1:
The patent merges the outputs from multiple tracking channels by combining their respective measurements (pseudorange, Doppler, carrier phase) into a unified navigation solution. The position engine integrates data from first, second, and third tracking channels, allowing the system to achieve improved reliability through redundant measurements while managing complexity through consolidated processing architecture
Solution Approach 2:
The patent implements feedback mechanisms where the position engine uses measurements from multiple tracking channels to continuously refine and validate the navigation solution. The system compares results across channels and uses feedback loops to adjust tracking parameters, improving reliability while maintaining manageable complexity through intelligent feedback control
3Manufacturing precision
If the measurement engine provides biased measurements due to multipath signals, then the ease of operation is maintained, but the manufacturing precision of navigation solution deteriorates
Solution Approach 1:
The patent extracts and isolates multipath signals from direct satellite signals by implementing separate tracking channels that can independently identify and process different signal types. The measurement engine is enhanced to distinguish between direct and reflected signals, extracting only the reliable direct signal measurements for navigation solution, thereby improving accuracy while maintaining ease of operation through automated signal discrimination
Data Source
AI summary
Novel tools and techniques are provided for implementing detection and estimation of direct and reflected navigation satellite (e.g., global navigation satellite system (“GNSS”), etc.) signal parameters in a multipath environment. In various embodiments, logic of semiconductor package that is disposed on a user device concurrently receives a plurality of signals from a satellite(s), each signal travelling along a different path between each satellite(s) and the user device within a multipath environment. The logic identifies two or more signal peaks that fall within a tracking aperture based on analysis of the received signals, and determines peak parameter estimates for each signal peak based on measurements of signal parameters from at least one signal peak. The logic provides the determined peak parameter estimates for each signal peak to a position engine (“PE”) of the user device to calculate a navigation solution (e.g., position, velocity, and/or time, etc.) for the user device.