SUPL Data Validity Period

[Thomas]

Hi,

I was wondering if you could give me information on the validity period of the GPS assistance data?

In other words, how often do you need to download the data? I can't seem to find any documentation on this?

Kind regards,

Thomas

[Martin]

I did some experiments with the SUPL library yesterday and have the same question.
I also could almost not detect a difference in speed to get to a position solution with or without AGPS data.

I am testing here in Brasil and the two networks with LTE-M do not seem to accept PSM and eDRX.
Testing protocol:
1. Let GPS get a position fix without LTE and SUPL (wait for 60 GPS fixes)
2. Sending every thrity second a UDP request and receive a reply
3. In the remaining time try to get a GPS fix
4. If SUPL is allowed it will get pulled during the first cycle 

Without SUPL and the a low 30s cycle GPS is normally lost after about 5 cycles.
With SUPL and a low 30s cycle GPS is normally only lost after 25 cycles.

That means that under these circumstances I need to switch off LTE for a time to recover the GPS signal ...

Best regards
- Martin