Wireless Terminal Position Reference Signal Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current location determination methods in cellular wireless communication networks face challenges when space-based reference signals are unavailable due to interference or obstruction, and there is a need for terrestrial-based systems to supplement or replace space-based systems, particularly for accurate location determination in scenarios like E911 compliance, where signals from multiple base stations can interfere, making it difficult to receive suitable reference signals.
Innovation Solution
A method and apparatus that utilize assistance data from a serving base station to manage the receipt of position reference signals from multiple base stations, including a white list of usable base stations and a black list of excluded stations, to determine time of arrival estimates, which are then forwarded to a location determination entity for accurate location calculation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the wireless terminal attempts to receive position reference signals from all base stations, then the location determination coverage is improved, but the signal interference increases and measurement precision deteriorates
Solution Approach 1:
The patent segments the set of base stations into two distinct groups: a white list containing base stations suitable for position reference signal reception, and a black list containing base stations to be excluded. This segmentation allows the terminal to selectively process signals only from approved base stations, thereby maintaining location determination coverage while eliminating interference from problematic base stations, thus preserving measurement precision.
Solution Approach 2:
The patent implements preliminary action by providing assistance data to the wireless terminal before the actual location determination process. This assistance data includes the pre-configured white list and black list of base stations, allowing the terminal to预先 know which base stations to monitor and which to exclude. This pre-filtering prevents the terminal from attempting to receive signals from all base stations, thereby avoiding interference and maintaining accurate time of arrival measurements.
2Reliability
If the wireless terminal receives position reference signals from multiple base stations, then the location determination reliability is improved, but the complexity of managing signal sources increases
Solution Approach 1:
The patent introduces an intermediary mechanism in the form of assistance data that includes pre-configured white lists and black lists of base stations. This intermediary provides the terminal with ready-made filtering criteria, eliminating the need for the terminal to independently evaluate and manage each potential signal source. The terminal simply follows the guidance in the assistance data, which reduces the management complexity while maintaining reliable location determination through multiple validated base stations.
3Adaptability or versatility
If the wireless terminal processes signals from all available base stations, then the adaptability to different environments is improved, but the time required for location determination increases
Solution Approach 1:
The patent applies preliminary action by providing assistance data containing white lists and black lists of base stations before the location determination process begins. This pre-processing allows the terminal to immediately know which base stations to monitor and which to exclude, eliminating the need to evaluate all available base stations in real-time. The terminal can quickly adapt to different environments by using the pre-configured lists while minimizing the time required for signal processing and location calculation.
Data Source
AI summary
The present invention provides for wireless terminal and a method in a wireless terminal for use in a location determination approach using time of arrival estimates between the wireless terminal and a plurality of base stations in a cellular network. The method includes receiving assistance data from a serving base station for use in receiving a position reference signal used to determine a time of arrival of one or more respective position reference signals from the plurality of base stations relative to a time reference, wherein the assistance data includes a list of base stations, each base station included in the list to be one of used or excluded from use as part of the plurality of base stations for receiving the position reference signal and determining the time of arrival estimate for the received position reference signal. The position reference signal is then received for each of the plurality of base stations, where for each of the plurality of base stations a time of arrival estimate is determined for each of the respective received position reference signals. The time of arrival estimates for each of the plurality of base stations is then forwarded to a location determination entity.