Validating LTE Time Assistance Data for Satellite Signal Acquisition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Satellite positioning systems face significant delays in signal acquisition due to the need to search a large two-dimensional space for satellite vehicle signals, which increases processing time and power consumption, especially when the identities of satellite signals are unknown, and can lead to undesirable delays in location determination, particularly in emergency situations.
Innovation Solution
A method for validating LTE base station time assistance data by receiving time assistance data via a first wireless communication technology and obtaining a reference global navigation satellite system (GNSS) time via a second wireless communication technology to determine the validity of the assistance data, allowing for a validated GNSS time to be determined and used for quicker signal acquisition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the receiver performs a cold start signal acquisition without prior time knowledge, then the receiver can acquire satellite signals, but the acquisition time increases to 5-10 minutes due to searching a large two-dimensional search space
Solution Approach 1:
The patent applies preliminary action by providing time assistance data to the receiver before the actual signal acquisition process. This assistance data includes time information that allows the receiver to skip the lengthy two-dimensional search space exploration and directly acquire satellite signals, reducing acquisition time from 5-10 minutes to a much shorter duration.
2Productivity
If the receiver continuously tracks SPS SV signals, then location determination is always available, but the device cost increases, battery life decreases, and primary functionality is reduced
Solution Approach 1:
The patent implements periodic action by having the receiver acquire SPS signals only when needed rather than continuously tracking them. The system can perform rapid signal acquisition using time assistance data when location determination is required, while remaining in a low-power state otherwise, thus extending battery life while maintaining location availability when needed.
3Power
If the receiver uses acquisition assistance information to narrow the search space, then the processing burden and power consumption are reduced, but the assistance information may be invalid due to incorrect configuration or rogue eNB
Solution Approach 1:
The patent applies feedback mechanisms to validate the time assistance data before using it for signal acquisition. The receiver can cross-check the assistance data against expected values or use feedback from multiple sources to determine whether the assistance information is valid, preventing the use of incorrect or rogue-provided data while still benefiting from valid assistance information to reduce processing requirements.
Data Source
AI summary
A method for validating time assistance data includes receiving, at a mobile device, the time assistance data via a first wireless communication technology from a serving cell. The method also includes obtaining a reference global navigation satellite system (GNSS) time, at the mobile device, via a second wireless communication technology and determining whether the time assistance data is valid based on the reference GNSS time. Further included in the method is determining a validated GNSS time based on the time assistance data in response to determining that the time assistance data is valid.