Offline AGPS sync?

deserthike20

I’ve been testing my S9 Peak regarding offline syncing of activities and routes to the phone app. There is some really useful stuff there for when there is no mobile data or WiFi available!

I’m about to do a week long mountain hike so I wanted to see if it possible to sync the cached AGPS file from the phone app back to the watch while being offline. This could be useful if the watch crashed for some reason……

So while completely offline I did the 10 second upper button push to clear the AGPS file on the watch and attempted to resync with the app. Both iOS and Android appear to sync the file (they both say Optimizing GPS Performance) but the watch never seems to get it. Under settings it just says N.A.

Once back online it syncs immediately as excepted and shows up in the watch……

Is this by design or does the Suunto phone app never really store that file to sync back if offline?

inkognito

@deserthike20

Just some thoughts:

If I remember this correctly, it can take up to 15 minutes for the watch to process the Assisted GPS data downloaded from the phone. Meanwhile it shows N/A. Well, I have S9, S9P might be faster, but I don’t know…
Assisted GPS is just a faster way to get the GPS almanac and ephemerides data. These are also broadcasted by the satellites, but it takes up to ~ 12.5 minutes to download the almanac via GPS signal (using single chanel).

So, in theory, you should be able to get all the data via GPS only within 15 minutes, which is comparable to processing of the Assisted GPS data downloaded from your phone. So, in practice, I don’t think that the sync you describe would really help you

Anyone to provide better info? I’m just a humble solid-state physicist

deserthike20

@inkognito Thanks for that. I do remember reading that the watch need some time to process that file.

I’ll try your idea and download it over GPS alone. I’ve actually never had the watch crash its just sometimes things happen when you really really don’t want them to.

isazi

@deserthike20 I’ve done week long trips with no internet, pretty sure your watch will work fine, especially considering you start and stop at the same location (I guess). Worst scenario, you’ll need to wait a minute for a good GPS lock.