P3 GPS/Glonass benefits

[edonovanl]

I am trying to understand how the P3s GPS/GLONASS system is better - does it provide redundancy, or just more satellites? During my research I found the following statement:

A GPS & GLONASS GNSS system is not normally any more accurate than a GPS only system under ideal conditions, both systems are very similar 70's technology, but will be more robust in non-ideal conditions when there are a lot of obstructions blocking the receivers view of the sky.

https://answers.yahoo.com/question/...1dJTUMwXzEEc2VjA3Ny?qid=20110515093245AAdXu8f​

For sure, much faster satellite acquisition, and possibly double the number of satellites so more dependable. Any other benefits?

​

 

[N017RW]

I am trying to understand how the P3s GPS/GLONASS system is better - does it provide redundancy, or just more satellites? During my research I found the following statement:

A GPS & GLONASS GNSS system is not normally any more accurate than a GPS only system under ideal conditions, both systems are very similar 70's technology, but will be more robust in non-ideal conditions when there are a lot of obstructions blocking the receivers view of the sky.

https://answers.yahoo.com/question/...1dJTUMwXzEEc2VjA3Ny?qid=20110515093245AAdXu8f​

For sure, much faster satellite acquisition, and possibly double the number of satellites so more dependable. Any other benefits?

​

Multi-constellation systems will always be better than single. There's a number of benefits and you hit all the big ones that matter to the users. That and improved accuracy.

Not sure about faster acq. That depends on the latency of the last almanac and ephemeris data loaded into the receiver's engine and the back-up duration of such data held in memory. Non-existent or invalid data will need to be downloaded prior to 'first fix' and that is at a fixed data rate so acq. time would be similar in those situations.

 

[edonovanl]

N017RW, you can always be counted on for a good comment! The speed of satellite acquisition really doesn't bother me and I don't think is a big deal, but the accuracy and less chance of losing satellites should help, especially new flyers. Personally, I fly mostly in ATTI and only use GPS if I happen to be recording video, which is rare...

 

[N017RW]

N017RW, you can always be counted on for a good comment! The speed of satellite acquisition really doesn't bother me and I don't think is a big deal, but the accuracy and less chance of losing satellites should help, especially new flyers. Personally, I fly mostly in ATTI and only use GPS if I happen to be recording video, which is rare...

Thank you.

One benefit of age is experience.
I'm not versed in everything r/c but a lot of my other interests are at work here and where possible I like to provide a link to my info. or other supporting documents.

C ya' 'round.

 

[Entropy512]

Out of curiosity - does anyone know if the P2V+ GPS receiver supported WAAS?

Given the rather poor TTFF it had, it seems like it was a pretty basic/crappy unit.

Ephemeride retention along with WAAS would make for some great improvements if those are in there in addition to GLONASS support.

My experience has typically been that for some reason, it takes MUCH longer for receivers to lock on to GLONASS sats than GPS sats - this has been the case for both Broadcom GPS receivers (original Galaxy Note) and Qualcomm's GPSOne solutions.

 

[N017RW]

Out of curiosity - does anyone know if the P2V+ GPS receiver supported WAAS?

Given the rather poor TTFF it had, it seems like it was a pretty basic/crappy unit.

Ephemeride retention along with WAAS would make for some great improvements if those are in there in addition to GLONASS support.

My experience has typically been that for some reason, it takes MUCH longer for receivers to lock on to GLONASS sats than GPS sats - this has been the case for both Broadcom GPS receivers (original Galaxy Note) and Qualcomm's GPSOne solutions.

According to the uBlox NEO-6 data sheet... Yes.
(P2s actually have the NEO-6Q)

I'm sorry I too lazy to post a link (I'm using a downloaded copy) but if you Google you'll find it.

The (P2) TTFF issue is further exacerbated by the low capacity of the supercap used for memory back-up.