40 ms·
If you're connected to an AP via Wifi, can't you ping the router? That would give you a single RTT data point, which you could combine with the non-RTT measurem
by cesarb 9y ago
If you're connected to an AP via Wifi, can't you ping the router? That would give you a single RTT data point, which you could combine with the non-RTT measurements to enhance the precision. The router is often either the AP itself, or linked to it through a wired connection.
Thinking more about it, you could even use an ARP ping (like the "arping" tool) to try to ping the AP directly, even if it's not the router.
- qrv3w 9y agoYes you can do that but that runs up against the problem of "processing time" in the router. A router might process a simple echo request for +/- 1 millisecond. Since 1 nanosecond = 1 foot, this variability already makes the distance measurement meaningless for indoor positioning. The way to do it accurately requires using something like 802.11mc [1] which can vary accurately measure time using frame collisions. [1] http://ieeexplore.ieee.org/document/6805649/ http://ieeexplore.ieee.org/document/6805649/