Galileo – 935, Fenix 5 Plus Accuracy Update

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I’ve probably spent a little too long recently looking at GPS (GNSS) plots of numerous runs that I’ve done, attempting to see if GPS+GALILEO offers any improvements over GPS-only or GPS+GALILEO.

In hindsight, the inordinate amount of time I spent looking at google map plots would have suggested, in itself, that there is no obvious answer.

The Obvious Answer

The conclusion that I came to was that:

  • Sometimes, GPS+GALILEO is slightly better at recording a plot showing where I’ve been.
  • Sometimes it’s about the same and
  • Sometimes it’s about the same in places and a bit better elsewhere BUT at the same time a bit ‘jagged’
  • Sometimes it’s truly awful and totally unusable.


Other Factors

Ref: DOP – Dilution of Precision (link to: wiki)

I’ve also used the GPS Plan app on IOS to determine the DOP conditions in various tests that I’ve done over the years. HDOP/TDOP/VDOP/PDOT conditions do vary where I live but the conditions tend to vary within the realms of Excellent-to-Ideal almost all of the time. Indeed on the very few occasions I have had a mere ‘Good’ level of PDOP I still had good tracks in those conditions.

However I’m not entirely sure if the stats I looked at worked out the DOP scores based on the entire constellation of GPS+GALILEO+GLONASS (I assume it did). Which makes the results and my time potentially meaningless and wasted, respectively. Grrr

However,  one thing that did stand out was that the number of available GALILEO satellites varied from 2 to 6 at my location. Quite low I thought (2).

You might have thought that buying a new watch to get access to two more satellites might be somewhat less than cost effective.

But, then again, it’s not the number of satellites that will necessarily give more accuracy. 2 GALLEO satellites in the right place in relation to the other GPS satellites could quite easily be better than 6 GALILEO satellites in ‘unhelpful’ locations.

Some Test Results


The Garmin Fenix 5S Plus (w/GALILEO) does seem to be an improvement over the 5S but is still not comparable to the better Suunto and Polar devices. There seems to be something generally wrong with running tracks that are not sufficiently smooth for my liking.

Jabra Elite Active 65t Review Garmin 5S Plus
5S Plus with Jabra Elite Active 65t

Whereas the Forerunner 935 w/GALILEO was actually pleasantly better than on previous run. I’m going to use my new app to plan the best time to get optimal GALILEO coverage and do a proper test run and see what it comes out with. It might, just might get close to the better Polar and Suunto models..or not. Then again, it’s 2 steps forward and the proverbial one step back. The one step back seems to be in open water performance where it’s defiantly not as good as before which seems to concur with Fenix 5 Plus performances elsewhere (link to

I had completed quite a bit of COROS Pace testing. COROS then released an improved GPS+GLONASS algorithm. Grrrr. But that *DOES* seem pretty good. Surprisingly so. It’s given me some excellent results that DO match the results of the best GNSS devices. #VeryPleasantSurprise

Instant Pace

I seem to be getting slower because of too much fiddling with gadgets. Maybe I should actually spend more time looking at how fast I am running?. Thus I’ve no feedback (yet) on any improvements to Instant Pace accuracy or otherwise. I would imagine that, at best, it might only be very slightly improved.


Take Out

Well I wouldn’t switch to a high-end Garmin right now just because of the GALILEO option. GALILEO wouldn’t be a factor for me AT ALL in a switch/purchase decision. Sure if you want to upgrade form a Fenix 5 to a 5 Plus because it won’t connect to your power meter then go for it….but that’s one of many other reasons to switch or trade up.

Indeed I would say that GALILEO currently has issues on the v2.20 GPS firmware. It’s fine to use it as a toy but it could go badly wrong eg me this week in a ‘C’ race.

If you are a 935 owner and feeling a little left out on the features front then you might want to think about my current, cunning plan. My cunning plan is to switch to a 5S Plus as my tri watch. That’s very much a W.I.P (work in progress) thing right now but that move will give me all the new non-sporty features that, of course, I won’t use too much 😉 But it will retain pretty much all of the sporty stuff that the 935 can do and it will do it in a similar sized/weighted format. Both have GALILEO. More to follow on the 5S Plus Switch.

COROS Pace Review M1 Multisport

If you are thinking of avoiding Garmin and getting a COROS Pace tri watch then that is starting to look like a more and more sensible move as the weeks go by. Especially with the apparently improved GPS+GALILEO. The lack of ANT+ support in last week’s firmware update was a cause for concern, although I was pre-warned of that. ANT+ is now scheduled to ‘later this month’ and ‘later this month’ is fast approaching. Maybe they’re actually testing it first to release sans-bugs??? Do companies actually do that any more 😉

Edited after a truly bad GALILEO experience


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Mirko Surf&Run

In august should become “usable” the 4 Galileo satellites that were launched in december 2017, they are now in the status “under commisioning”. See
But 6 satellites in view are quite a good number, it seems that we won’t see other substantial accuracy improvement any time soon without using other gnss technologies 🙁
Unfortunately I can’t find any detailed review about the Xiaomi Mi8, first android smartphone with a dual frequency Galileo chipset. The first tests seem to show (perhaps) that the android app are still not ready to take a real advantage of the second Galileo frequency (frequency E5b). See “Dual-frequency GNSS on Android devices” of Sean Barbeau .
In the 8 July Sean wrote that till today no one has done an accuracy test of the dual frequency galileo with the xiaomi Mi8.

Mirko Surf&Run

The Xiaomi has inside the famous dual frequency gnss chipset of Broadcom BCM47755 and can give simultaneous reception of GPS, GLONASS, BeiDou (BDS), Galileo (GAL), and SBAS satellite systems. Important for us in Europe, it can receive the dual frequency of GPS (L1 and L5) and dual frequency of Galileo (E1 and E5a). The GPS constellation has fewer dual frequency satellites, because the older satellites have just one frequency. But the newer GPS satellites have also dual frequency like Galileo. In the website I cited above, you can see which GPS satellites have dual frequency in a screenshot of a xiaomi MI8 of a user who uses the app gpstest You can see that he can receive a lot of satellites with dual frequency. If I understand correctly, the big problem with the Xiaomi Mi8 now is not the DOP stuff, but the firmware that is not yet ready to use these dual frequency, if I understand correctly the website i cited above. Probably it’s not so easy to use this second frequency. I read somewhere in the web that the Xiaomi Mi8 is now wildly inaccurate (I read 16 meter accuracy, while in comparison the single frequency gps… Read more »

Mirko Surf&Run
here they say that with the new firmware xiaomi mi8 has 4 meters accuracy
the user can see 3 dual frequency galileo satellites and 3 gps dual frequency satellites (and other single frequency) and the PDP is good

Mirko Surf&Run

Correction, I wanted to write PDOP not PDP

Mirko Surf&Run

In the same web site cited above of Sean Barbeau, a user (Marco Samuel in Austria) on 25th July tested the Xiaomi MI8 (firmware MIUI version next to the GPS antenna of a dpgs receiver NovAtel with an accuracy of 2 cm. He says that it does not seem that dual frequency gps is working at the moment in the phone xiaomi MI8 (in the graphics we see that errors is about under 5 meters, I think that for a stationary gps receveir in open sky with just one frequency accuracy should be about the same).


Marco Samuel used firmware MIUI9 (in particular
Another user in the xda-developers forum, Rodfrang, had good accuracy of 1-2 meter walking and driving a car changing the firmware from 9 to the firmware MIUI 10 (in particular MIUI10.8.7.6 China beta ROM ). This new firmware gave in the phone the icon “Dual GPS”


Thanks for this review. It confirms my choice. I was in doubt whether to choose Suunto 9 or Fenix 5X Plus. I choose Suunto 9, because i value accuracy the most 🙂


where do you find information about coros new firmware releases? thanks 🙂


ok, thank you very much 🙂

Guillermo Guerini

Last week, after updating my 935, I decided to use “GPS only” instead of “GPS + Glonass” or “GPS + Galileo”. To my surprise, the results were much better. I live in Boston and there aren’t many tall buildings here. I usually run by the Charles River so 80% of my run are wide open for miles. When I run by the river, both “GPS only” and “GPS + Glonass / Galileo” track the route perfectly. But until I get to the river, I run by many buildings and the “GPS only” works better (but it’s not perfect). I will give Galileo another try when the new Galileo satellites are launched. For now, I will stick with GPS only.

Mirko Surf&Run

Strange, in theory in open field (when you run by the river) the option GPS only should give the same accuracy than GPS+Galileo. Near building Gps+Galileo should give better results because there are more satellites and the PDOP should be better (the position of the satellites) than GPS alone.
As always, theory is different that reality.


From my tests , Fenix 5S Plus (Galileo) owns both FR935 or Fenix 5 in terms of accuracy (there is no comparison (firmware 3.20) and I have actually compared the same track. I was very impressed by the accuracy of the 5S Plus , sometimes detecting even change of direction for like 1-2 meters and I compared both morning tracks and evening (to see if galileo positioning makes a difference)

I am not even sure how it can be possible to get better results than that.

You are complaining about the “smoothness”. That I believe is also the result of the processing factor ( like Garmin Connect or Strava) not just the watch. I am very pleased with what I got with my fenix 5s Plus considering all my tracks are city based.


too bad I can’t upload pics to see what huge difference it was in terms of accuracy. Even the Edge 520 fails in terms of accuracy compared to the 5s Plus.


Btw , if it wasn’t clear enough – Fenix 5 andd 935 did not have the update that added Galileo option.


Nope , as I don’t have the Fenix 5 , FR935 and Edge 520 anymore and they didn’t have Galileo back then but I do cycle at the same exact hours each day and have the same path so I know when one would give me inaccuracies. Frankly my 5s Plus provided the most consistent and accurate results with Galileo.

For some reason my evening results are better than the ones in the morning (gps / galileo positioning?) idk. – 5s Plus – Edge 520 – FR935

5s plus > Fr935 > Edge 520.

Mirko Surf&Run

I can’t try this app because I don’t have Iphone with ios. But I presume that the app gives the DOP value and the number of satellites only in open sky. Near building the number of satellites is less and the DOP increases a lot. Or the app can evaluate also the presence of building?

Mirko Surf&Run

GSAT0216, GSAT0217 and GSAT0218 (SV ID 25, 27 and 31) are now usable as from 2th august. They were launched 15th december 2017.
See Galileo constellation information status report.
There are now 17 Galileo satellites in “usable” status.

Mirko Surf&Run
In this thread we see that the Galileo ID25 satellite appears now in the app Gpstest.
They are finding accuracy of the dual frequency xiaomi mi 8 between 0,5 m and 4 meters while driving. The problems on the phone firmware are still not completely resolved (I don’t understand very much what is the issue, it seems a bit complicated).

Mirko Surf&Run

Sorry the5krunner, with the three new usable Galileo satellites, I think it’s time you do another update of your GPS+Galileo test 😉

Mirko Surf&Run

When you do the next test, can you control with some app at the beginning and at the end of the run how many Galileo satellites are in view in open sky, and report it in your review?


With the url that a user gave to control the number of satellites in a location and in a certain time (see the the first post “Galileo: is it rubbish?”,, I see that in London right now should be 6 Galileo satellites (actually appear a total of 8 satellites, but Gal E22 is not usable – see and Gal E21 is the fourth satellite that was launched on december 2017 but unfortunately is still “under commisioning” and still not “usable”.) Gal E21 should in theory become usable in a short period,because it’s 7 months that it is “under commisioning”, the other three that were launched together are still usable from the beginning of august. I see that the satellite Gal E21 has an height over the horizon of 85°, while the other have an height over the horizon between 9° and 38°. Gal E 21 should be very important because it’s exactly over our head, so it should be always be visible, no problems with building. It should be also very important for the DOP factor, because with this satellite we can have a good geometry. The5krunner, maybe you should wait that Gal E21 becomes usable, before making… Read more »


Satellite Gal E21at 18:34 o’clock today has now an elevation of just 0° above the horizon direction ENE, and probably in a short time it will not be in view any more.
Now there are two other Galileo satellites high in the sky (GAL4 height 77° direction SSE, GAL 11 height 72° direction SSW). But the position vary quickly.
You are right, on satellite more or less doesn’t make a huge difference.
I forgot that Galileo satellites are not geostationary like ad example WAAS satellites, but they move quick in relation to the rotation of the earth, so we have above our heads always different satellites.


Right now in London of the new three satellites that became “usable” on the 2th of august, only GAL27 is visible (it has an height over the horizon of 25° and direction ESE), the other two satellites (GAL25 and GAL 31 are not visible, probably they are now visible from other continents).

Mirko Surf&Run

21:30 o’clock on 6th august 2018 location London.
9 Galileo satellites in view, but Galileo 21 is under commisioning and Galileo 22 is not usable, so real satellites in view are 9-2=7
About the 4 satellites that were launched in decembre 2017
Satellite Galileo 21 (the satellite still under commisioning) is 4° above the horizon and direction NNE
Satellite Galileo 25 is always not visible
Satellite Galileo 27 is no more visible
Satellite Galileo 31 is now visible (25° above the horizon direction ESE)
It seems to me that of these 4 new satellites, in average 2 are in view. The satellites and their position change very rapidly during the day.

Mirko Surf&Run

I think that in the spreadsheet of result you should also exclude the satellites with an elevation above the horizon less than 10° or 15°. I think that under that elevation it’s very difficult to see during the run these satellites. I don’t know if the Ios app exclude automatically the satellites under that height. Right now in London (22:28 the 15th august) there are 8 Galileo satellites, but I would exclude GAL E24 and GAL E30 because they have an height of 1° and 12° respectively and so I think they are too low on the horizon. I would say that right now there are 8-2=6 usable Galileo satellites that can be viewed by the gps receiver of the sport watches.
I’m surprised how quickly the satellites are moving, just one hour of time gives a noticeable difference of the satellites in the sky.

Mirko Surf&Run

Looking at the images of the satellites in the website that Luis Pinto suggested (>spacecraft->Satellites in your sky) I think that in open sky the DOP is always good for all constellations in every moment of the day, because all the three constellations (GPS, Galileo and Glonass) have a good number of satellites and with a good position in every moment of the day. The problem is that DOP becomes very important near buildings and near other obstacles like mountains that don’t let see some satellites any more. What we need is an application that shows how DOP varies along a track during a run and register it so we can read these values in a graph after the run. It would be nice if there is an IQ app so that we can see the DOP value in Garmin Connect for the entire run, like for example we see the cadence. I think that the firmware of Garmin should know what is the DOP number second after second, because when the firmware chooses which satellites to use, perhaps it takes his choice not only evaluating the strength of the signals of the satellites, but perhaps it takes the satellites… Read more »

Mirko Surf&Run

I just saw with better attention the ios app gps-plan : it seems that it gives good graphs of the DOP values . But if you run with your iphone, the DOP value increases near building? If so, it seems the app we were looking for.
Are you sure you can’t choose which constellation to use in the settings of gps-plan?
For example if you run with the Fenix 5s with “gps only”, maybe you can run with your iphone near the fenix and select in the app gps-plan the option: turn off galileo and turn off glonass.
In the second run, with the Fenix 5s with gps+galileo and the iphone you switch off only glonass.
But you should run also with your phone, because DOP values changes near building (I tested it with the android app gpstest).
If you can’t switch off some constellation in gps-plan, it is nethertheless a good graph to look into.

Mirko Surf&Run
In this comment Barbeau, the author of the android app gpstest, explains how to get the dop value with NMEA strings that gps receiver use.
Extract:” GSA – GPS DOP and active satellites. This sentence provides details on the nature of the fix. It includes the numbers of the satellites being used in the current solution and the DOP. DOP (dilution of precision) is an indication of the effect of satellite geometry on the accuracy of the fix. It is a unitless number where smaller is better. For 3D fixes using 4 satellites a 1.0 would be considered to be a perfect number, however for overdetermined solutions it is possible to see numbers below 1.0.”
Is there already a Connect IQ app that can show DOP value? Or if it doesn’t exist already, maybe a smart developer can write a good IQ app for Garmin?
Dom? McBadger? 😉

Mirko Surf&Run

In the garmin forums they write that garmin doesn’t allow to have dop values with ciq app. Extract of the forum: “04-29-2017, 12:34 AM ***QUESTION***Originally posted by kangsterizer When Glonass is in use I believe it works like any other device.. its GPS + Glonass, not GPS or Glonass. Having more positioning data just means more precise / accurate geolocation in this case. Basically you might have 5m accuracy on GPS, and 1m if you turn on Glonass (this is a fictious example). Most recent phones have GPS and Glonass with apps where you can test exactly the same thing as well, though it’d be interesting to have an IQ app on the watch that shows the satellites locked that are GPS vs Glonass and/or accuracy (I don’t know if that already exists/is possible on the watch) ***ANSWER***You’re right, it’s either GPS or GPS+GLONASS. Having GLONASS enabled as an additional source of information can improve position accuracy in situations where GPS coverage is poor due to the number of visible GPS satellites. If GPS performance is poor due to environmental factors (high rise buildings, underpasses, dense wet foliage overhead) then GLONASS is likely to be affected in the same… Read more »

Mirko Surf&Run

I remembered wrong and what I writed about QZSS is not correct. But I’m not interested in QZSS because these satellites are visible only in regions near Japan, so if you want correct information see wikipedia.

Mirko Surf&Run In the official japanese page of qzss, we can see important information and we can see what could be achieved with Galileo when Galileo will be fully operational. QZSS is not yet fully operational in Japan, but they are still testing it (they use the words “start of trial-service”) and I just read that they stopped their services because there are some hardware problems with some satellites. The only satellite that is geostationary is QZS-3, the others not. But QZS-3 is now not operational because it has problems. But the important thing is that these services are freely available to the users, when they are avalilable. When QZS-3 was functioning, it started his trial services in december 2017 The most important services are: 1- Satellite Positioning, Navigation and Timing Service (PNT) 2- Sub-meter Level Augmentation Service (SLAS) 3- Centi-meter Level Augmentation Service (CLAS) The question now are three: 1- When will start Galileo similar services (SLAS and CLAS) ? Officially they say in 2020 with the E6 frequency, but maybe they are quicker. 2- Will these services be freely available without fee for the users? 3- There is a chance that sport watches could benefit of these additional services?… Read more »

Mirko Surf&Run
Beautiful description of the service of QZSS SLAS (Sub-meter Level Augmentation Service), that could be useful for sport watches.
In short, they say that it’s a more affordable way to have sub meter accuracy compared to dual frequency. They say that dual frequency receiver are expensive.
If I understand correctly, it’s a similar service that WAAS and Egnos satellites are giving now in America and Europe.
If also Galileo gives a similar service it would be nice, because WAAS and Egnos are too low on the horizon (they were designed for airplanes) and they are hard to see for the normal user (for the runner or hiker). If also Galileo begins to give this service (like QZSS is trying to do in Japan), we are sure to also receive this service also in difficult environment.
The Fenix 2 used WAAS. Fenix 5 is not known, maybe yes o or maybe not (perhaps Garmin thinked that WAAS doesn’t give a good advantage for sport watches, so Garmin decided to not use WAAS any more).


I have to do another correction, I writed that the chinese Beidou satellites are not geostationary. I just read in Wikipedia that some Beidou satellites are geostationary, but the most are not geostationary.

Mirko Surf&Run

Sometimes Europe can be very stupid

Mirko Surf&Run

I had a discussion about Garmin Fenix and WAAS with Dom in the DCRainmaker review of the Garmin EDGE 130. At the end we couldn’t find a definitive answer. Maybe you or DCR could further investigate about it. I think that it’s quite important because Galileo declared that in 2020 it will give an error correction service with centimeter accuracy for free with the E6 frequency – maybe also before 2020, they are probably choosing who will give this type of service or are preparing the ground infrastructure (PPP – Precise Point Positioning). In order to use the PPP service, you need a PPP enabled device. Someone told me in that thread that centimeter accuracy is “overkill” for a sport watch and it is definitely; PPP has also big problems in urban environments because if it looses the track, it has long convergence time (10 – 15 minutes) before it gains the centimeter accuracy again. In the meanwhile it functions like a normal device with standard accuracy. But if Galileo gives also a submeter accuracy service, similar to that that WAAS in North America and QZSS in Japan are giving now, it would be a more economical solution to obtain… Read more »

Mirko Surf&Run

I just read that also the chinese Beidou satellites constellation gives a similar service like WAAS and QZSS.
The accuracy of Beidou for civilian user is 10 meter, with the error correction service accuracy is under 1 meter. This error correction is given by some geostationary satellites and is given only in regions near China.
I’m wondering if also Galileo is planning to give an error correction service like WAAS that could give submeter accuracy. Till now unfortunately I couldn’t read anywhere that this will be provided.
But if Galileo planned to give in 2020 with the E6 frequency centimeter level accuracy for PPP enabled receivers, perhaps they are also planning to give submeter accuracy for normal receivers with an error correction service like WAAS.
Come on Europe, Japan and China can’t be more intelligent than you…


I’m controlling Tokyo for some times with the website “”. It is true, there is always one QZS satellite with a minimum height of 80° above the horizon in Tokyo.
Europe, this is how you must give a SBAS correction service!
The name QZSS ” Quasi-Zenith Satellite System ” corresponds to reality. Japanese are very clever!
I wish that Galileo begins to give this type of service (SBAS) indipendently, without the support of WAAS and EGNOS.
I don’t know if it is possible, because QZSS has a dedicate frequency to transmit the sub-meter error correction service (frequency L1S). Till now, it seems to me that Galileo has not a dedicate frequency to transmit an error correction service. Or maybe Galileo could transmit this error correction service inside the code of the normal frequency E1?

Mirko Surf&Run

Polar GPS sensor G1 and G5 had the possibility to use WAAS and EGNOS. But when they used WAAS, it was no possible to utilize an energy save mode for the battery.
I think that the G1 and the G5 sensor are no more in production.
It is to verify if the new gps sensor of Polar are compatible with WAAS (for what it’s worth, because the visibility of WAAS satellites is not good).

Mirko Surf&Run

h t t p s : / /
Always in the page of Sean Barbeau of the first post, we see that a user on the 24th august writed that the Broadcom chipset BCM47758 will be installed in the watch Samsung Gear.
This chip can give simultaneously dual frequency GPS and Galileo.
After the big delusion of the Xiaomi Mi8, we’ll see how if this watch well behave.

Mirko Surf&Run

I agree that the big con of dual frequency is the battery hit. I think that the bigger impact on battery is not dual constellation (for example GPS+Galileo), but the use of multiple frequency (for example two frequency, L1 and L5 for GPS and E1 and E5 for Galileo). I think that during tracking the firmware decides which satellites to use (choosing the strongest signal or the best position), so having the choice of one or two constellation of satellites doesn’t change much the power consumption, because I think that for watches at the end of the story the firmware just use 4 satellites (GPS or Galileo)x 1 frequency = 4 signals. With dual frequency the firmware have to track 4 satellites x 2 frequency = 8 signals, so maybe circa the double power requirement. NOTE: this is just my pure speculation and not supported by technical data Broadcom for his chipset BCM47755 (for phone) and BCM47758 (for watches) declared that the power consumption is low, and not greater of the current single frequency chipset, for two reasons: 1- new production mode of the chip with less nanometers . 2- they said that they wanted to fix the satellite signal… Read more »

Patrick Sledge

How accurate is the GPS in terms of measuring the correct distance vs mapping coordinates. For example, if I run three miles, and the surface that I am running on is accurate and measured, but GPS is reading a distance shorter than actually ran.

I have the Fenix 3 and I am willing to upgrade to the 5x plus but I won’t until reviews on the distance accuracy can be adequately answered or more people purchase this version of the watch and give an honest assessment. I currently have to run measured routs to ensure I am running correct distances whether its on a track, course or street. Correct distances are my main concern.

Mirko Surf&Run

Galileo GSAT0215 (also known as Galileo E21 – space vehicle ID ) is usable from 12th october 2018.
There are now 18 usable Galileo satellites.

DATE GENERATED (UTC): 2018-10-12 10:30

NAGU NUMBER: 2018023
START DATE EVENT (UTC): 2018-10-12 08:07


Mirko Surf&Run

Font Sean Barbeau
Huawei Mate 20 and Mate 20 Pro

Huawei launched the Mate 20 and Mate 20 Pro on October 16, 2018, and — tl;dr — it supports dual-frequency! However, there is a twist. Instead of using the Broadcom chipset, these devices use the Kirin 980, which is also being marketed as the “World 1st 7nm Mobile AI Chipset”. But, more importantly for this article, the Kirin 980 website says:

The GPS is supported by industry leading L1 + L5 dual frequency ultra-precise positioning to give you a more accurate target location when using map navigation, even in complex terrains.

And, the Mate 20 Pro site says:

By leveraging L1&L5 dual frequency simultaneously, HUAWEI Mate 20 Pro allows you to always find the destination with great accuracy even in city centres surrounded by skyscrapers or highway interchanges.

And it looks like dual-frequency extends to Galileo and QZSS too, according to the specs:

GPS (L1 + L5 dual band) / AGPS / Glonass / BeiDou / Galileo (E1 + E5a dual band) / QZSS (L1 + L5 dual band)

Mirko Surf&Run

Now people in USA will have similar results of people in Europe with GPS+Galileo enabled with the Garmin watches, probably before Garmin watches in the USA didn’t use Galileo satellites even if the option GPS+Galileo was enabled.
Perhaps Polar will now give the option GPS+Galileo in the Polar Vantage?
Unfortunately from your reviews it doesn’t seem that single frequency Galileo helped GPS to increase accuracy in sport watches. But maybe we have to blame the chipset and power saving mode of the watches and not Galileo. Maybe in sport watches the weakness depends not on the satellites, but on the swinging of the arm while running and on the power save mode for better battery life .

Mirko Surf&Run

John, a user in the DCRainmaker Garmin130 comments, shared this link:
Extract from GPSworld:
“While private users were free to use the European GNSS, with this ruling entities such as telecommunications companies can now also use Galileo.”
Gpsworld says that this limitation was not for private users, so maybe garmin watches could receive Galileo satellites also before the FCC rule of 15 november 2018.

Mirko Surf&Run

I mean in the USA, no problem here in Europe