SBAS satellites and other correction systems

[Костя Стаханов (Константин Кривбасс)]

My phone sees these satellites (they come in different types). But I don’t understand if the GPS module works with them? Judging by the fact that there is no U icon in the fifth column, they don’t participate in calculating the location. Are there any phone models that work with these/similar satellites? Or ground-based differential correction systems?

[Sean Barbeau]

See https://issuetracker.google.com/277837966#comment4:

>Due to signal characteristics of SBAS and mobile devices, decoding the Navigation Message and getting a signal of high quality is a challenge. We checked with other chipset manufacturers and no one is using SBAS for positioning at the moment.

Sean

[Костя Стаханов]

Please tell me why MediaTek can give phase measurements, but Qualcom can't? Maybe because of this the GPS GPStest:Navigation app gives results with an accuracy of 1 meter?

С уважением, Константин С

вт, 24 сент. 2024 г., 17:55 'Sean Barbeau' via GPSTest <gpstest...@googlegroups.com>:

--
You received this message because you are subscribed to a topic in the Google Groups "GPSTest" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/gpstest_android/dIIHZUIbF1A/unsubscribe.
To unsubscribe from this group and all its topics, send an email to gpstest_andro...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/gpstest_android/286e0124-8830-4ca9-83dd-f0ce36ddeafdn%40googlegroups.com.

[Sean Barbeau (xWF)]

To my knowledge the only device with a QCOM chipset that has supported ADR/Carrier Phase has been the Pixel 4 and 5 series.

You can look this up in the GPSTest Database - see:
* https://barbeau.medium.com/crowdsourcing-gnss-capabilities-of-android-devices-d4228645cf25

* https://bit.ly/gpstest-device-database

Let me know if you find other examples.

Sean

[Костя Стаханов]

Thanks for the answer Sean! But that's not quite what I was asking - why do you think MediaTek gives out phase measurements, but Qualcomm doesn't? That's the first thing.
And the second thing - maybe because MediaTek gives out phase measurements, smartphones with it show in the program (https://play.google.com/store/apps/details?id=com.chartcross.gpstest&hl=ru  ) an accuracy of 1 meter?

С уважением ,Константин С.

вт, 24 сент. 2024 г. в 19:02, Sean Barbeau (xWF) <barb...@xwf.google.com>:

[Sean Barbeau (xWF)]

> why do you think MediaTek gives out phase measurements, but Qualcomm doesn't? 

I suggest reaching out to the chipset or device OEM and asking this question directly. Please post a response here if you receive one.

>maybe because MediaTek gives out phase measurements, smartphones with it show in the program (https://play.google.com/store/apps/details?id=com.chartcross.gpstest&hl=ru  ) an accuracy of 1 meter?

This value is just an estimated accuracy computed by the chipset and doesn't necessarily represent better real-world accuracy. See https://barbeau.medium.com/measuring-gnss-accuracy-on-android-devices-6824492a1389.

[Костя Стаханов]

They (the manufacturers) will not answer me. Maybe some journalist or organization, but not a private person. I know that the accuracy value there is very approximate, but Qualcomm in the same conditions shows 3-5 meters.

С уважением ,Константин С.

вт, 24 сент. 2024 г. в 19:34, Sean Barbeau (xWF) <barb...@xwf.google.com>:

[Sean Barbeau (xWF)]

Related - a new version of GnssLogger is rolling out now (v3.1.x) that includes a Measurements tab:

https://play.google.com/store/apps/details?id=com.google.android.apps.location.gps.gnsslogger

On this screen you can see the "# usable ADR" signals. On devices that don't support ADR/Carrier Phase this value will be 0.

Sean