Offset calibrations of some WiFi access points with one-sided FTM RTT
requests obtained using the WifiRttScanX app:

Offset is the difference between the reported and the true distance
(i.e. what needs to be subtracted from reported RTT distance).

With respect to Google Pixel 5 and earlier:

AP		freq (chan) offset (m)	st dev	outliers

Google Wifi	2437 (6)	2603.7	2.4	0%
Google Wifi	2462 (11)	2603.1	1.9	4%
Google Wifi	5745 (149)	2706.9	2.4	0%

Google Nest Pro	2412 (1)	2569.4	2.7	1%
Google Nest Pro	2462 (11)	2568.4	2.5	1%
Google Nest Pro	5180 (36)	2435.1	3.3	1%
Google Nest Pro	5745 (149)	2439.2	2.5	0%

Linksys Velop	2427 (4)	2629.3	1.9	27%
Linksys Velop	2452 (9)	2627.7	1.8	5%
Linksys Velop	5180 (36)	2711.2	2.8	0%
Linksys Velop	5785 (157)	2701.7	1.7	0%

Eero		2412 (1)	2548.7	2.1	23%
Eero		5180 (36)	2712.5	4.2	9%
Eero		5745 (149)	2706.6	2.1	11%

Netgear Orbi	2427 (4)	2627.8	3.0	1%
Netgear Orbi	5240 (48)	2711.0	2.5	0%
Netgear Orbi	5785 (157)	2700.3	2.2	0%

Starlink router	2412 (1)	2632.0	2.0	16%
Starlink router	5240 (48)	2705.1	2.8	0%

Aerohive 230	2462 (11)	2574.1	4.7	18%
Aerohive 230	5180 (36)	2410.1	6.7	29%

AeroHive 330	2412 (1)	2431.7	2.4	16%
AeroHive 330	5220 (46)	2386.0	2.5	13%

AeroHive 350	2412 (1)	2433.0	2.0	14%
AeroHive 350	5220 (1)	2435.3	1.9	4%

Aruba 3xx       2462 (11)	2640.6	5.5	33%
Aruba 3xx       5320 (157)	2525.5	8.3	11%
Aruba 3xx       5785 (157)	2784.8	4.0	6%

---

With respect to Pixel 6 and later:

AP		freq (chan) offset (m)	st dev	outliers

Google Nest Pro	2412 (1)	3166.0	1.4	2%
Google Nest Pro	5180 (36)	3039.0	3.9	0%
Google Nest Pro	6935 (177)	1833.0	4.9	2%

---

st dev:	standard deviation of 100 measurements taken at the same distance,
with burst size of 8 (i.e. *not* the st dev reported by the API).

outliers: RTT values rejected for various reasons, mostly because of large 
st dev reported by the API.

The offset calibrations were done with true distances starting at 0.5 m, with
increments of 0.5 m, ending at 8 or 10 m. 
(For the Aruba 3xx, steps were instead 2.1 m and went up to 60 or 70 m)
At each distance, estimated values were read every 100 msec for 10 seconds total.

---

Note: For comparison, two-sided offsets are typically a few meters, often less than one meter.
Note: For comparison, two-sided stdev are typically half a meter to one meter.