GNSS Signal Combination for Multipath Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Global navigation satellite systems (GNSS) face challenges in combining signals from different constellations effectively, particularly in challenging environments like urban canyons, where multipath and non-line-of-sight signals interfere with signal reception, leading to reduced accuracy and reliability.
Innovation Solution
A method and apparatus for combining GPS L1 C/A and L1C signals, as well as other GNSS signals, by determining correlations over specific periods, summing and modifying them to generate a combined satellite signal that improves signal-to-noise ratio and mitigates multipath effects, using a processor and non-transitory computer-readable media to adjust reception parameters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If signals from different GNSS constellations are combined, then signal-to-noise ratio is improved, but signal interference from multipath and non-line-of-sight effects worsens
Solution Approach 1:
The patent combines correlation values from multiple signal types (e.g., L1 C/A and L1C signals) within the same constellation and across different constellations. By merging these correlations and applying appropriate weighting, the system improves signal-to-noise ratio while maintaining robustness against multipath interference through diversified signal sources
Solution Approach 2:
The patent dynamically adjusts weighting parameters assigned to different signal types based on their individual quality metrics. By changing these parameters adaptively, the system optimizes the contribution of each signal type to the combined correlation, thereby improving overall reception quality while mitigating the impact of signals affected by multipath or non-line-of-sight conditions
2Measurement precision
If multiple signal types are processed and combined, then positioning accuracy is improved, but computational complexity increases
Solution Approach 1:
The patent segments the signal processing into distinct stages: individual correlation computation for each signal type, quality assessment of each correlation set, and final combination with weighting. This segmentation allows complex multi-signal processing to be broken down into manageable steps, improving positioning accuracy while controlling computational complexity through structured processing
Solution Approach 2:
The patent implements selective processing where not all signal types are processed with equal depth. Based on quality metrics and environmental conditions, the system applies partial processing to certain signals or skips processing of signals likely to be affected by multipath, thereby achieving good positioning accuracy without the full computational burden of processing all signals equally
Data Source
AI summary
Apparatuses and methods of manufacturing same, systems, and methods are described for combining received and correlated Global Navigation Satellite System (GNSS) signals and using the combined signal for improving GNSS reception in, inter alia, challenging environments. In one aspect, a first correlated GNSS signal and a second correlated GNSS signal are stored and then combined, and the combined signal is used to adjust reception of the first GNSS signal and/or the second GNSS signal. If the first and second correlated GNSS signals are stored by unequal time periods, time periods of one or both are added together until the total added first correlated GNSS signal is the same length of time as the total added second correlated GNSS signal. In order to properly combine the GNSS signals, gain/balancing factor(s) may be applied, the polarity of one or both may be flipped, etc.