Broadcast FTM Scheduling for Multi-STA Wireless Ranging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing FTM techniques require high bandwidth and multiple iterations for each pair of wireless devices, leading to inefficiency and potential privacy concerns due to overhearing by unintended listeners.
Innovation Solution
Implementing broadcast transmission and AP scheduling to reduce the number of messages required for FTM, allowing devices to determine ranging efficiently while preserving privacy by limiting transmissions to those not concerned with location exposure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional FTM techniques are used for multiple STAs, then positioning accuracy is achieved, but bandwidth consumption increases and efficiency decreases
Solution Approach 1:
The patent merges FTM operations for multiple STAs into a single coordinated process. The AP schedules FTM sessions for multiple STAs sequentially using a unified message schedule, allowing the system to achieve positioning accuracy for all STAs while reducing overall bandwidth consumption and improving efficiency compared to independent FTM executions.
Solution Approach 2:
The patent implements periodic FTM message exchanges scheduled by the AP. The message schedule defines specific time intervals and sequences for FTM messages between the AP and multiple STAs, creating a structured periodic action pattern that optimizes bandwidth usage while maintaining positioning accuracy through repeated measurements.
2Measurement precision
If multiple FTM iterations are performed for each STA pair, then positioning accuracy improves, but time consumption and bandwidth usage increase
Solution Approach 1:
The patent applies preliminary action by having the AP pre-calculate and broadcast a message schedule to multiple STAs before FTM executions begin. This schedule optimizes the sequence and timing of FTM messages in advance, allowing multiple STAs to participate in coordinated FTM iterations simultaneously, thereby reducing total execution time while maintaining positioning accuracy through multiple measurements.
3Productivity
If FTM messages are broadcast to multiple STAs, then positioning efficiency improves, but privacy exposure increases for participating devices
Solution Approach 1:
The patent applies local quality by differentiating the roles and privacy requirements of different devices in the FTM process. The AP, which is not concerned with location privacy, performs scheduling and coordination functions that are visible to all STAs. The STAs, which require privacy protection, participate in FTM measurements without exposing their locations, as the AP handles the scheduling and message coordination centrally.
Data Source
AI summary
Techniques for wireless communication are disclosed. These techniques include defining a message schedule for fine time measurement (FTM) at a first wireless access point (AP). The techniques further include broadcasting the message schedule to a plurality of wireless stations (STAs) from the first AP. The techniques further include receiving, at the first AP, a plurality of FTM messages from the plurality of STAs, the messages transmitted by the plurality of STAs based on the message schedule. The techniques further include determining a distance between the first AP and each of the plurality of STAs based on the plurality of FTM messages.