Xiaomi released a phone with dual frequency GNSS in 2018 (with the Broadcom BCM4775 chipset), and as far as I know most Android phones have had it since then, or maybe a bit later. If you want to see if your phone supports it, try GPSTest.
Garmin has recently released several watches with it as well, both their high end models and some more affordable ones. They also have an auto mode that switches it on or off depending on if the current environment needs it, to save power when you can have the same accuracy without it.
Personally, I find the accuracy and sensitivity of modern GNSS devices amazing. I remember when you had to wait maybe 10 minutes to acquire a fix, the accuracy was poor and maybe within 10 meters, and if you covered the receiver with clothing you would lose satellite fix. Now my phone gets a good position in a few seconds, I can see which side of the road I ran on, and even with my phone in my pocket I can often get a reasonably accurate track indoors.
The speedup you are noticing is probably mostly due to assisted gps, where your phone gets a location using - partial gps information + wifi location + cell tower location all triangulated. Your eg early 2010 car gps unit didn't have any of the addition ways to speed up the location fix
There are three things that lead to fast lock times for cell phones.
* Ephemeris and almanac data updated via the internet so the receiver doesn't have to wait for either and can immediately know what satellites to listen for and acquire.
* Precise clock via NTP so the receiver has a smaller solve space for its internal clock
* AGPS gives a very good position fix to further help with the initial clock and position solving
Apple has supported GNSS since the iPhone 8/X generation in 2017. This is about L5 GPS which I'm not sure how well this is supported in general ATM as its pretty new
GNSS is a generic term for satellite based positioning systems. It looks like you're referring to the iPhone adding Galileo support in the 8/X.
L5 support has been available in a number of devices for a couple of years now. Garmin was one of the first to use L5 in commercial devices, with their Fenix watches a while back.
The phone I'm currently using, the Pixel 6 Pro uses the L5 band. It's nice and I can definitely tell a difference, but it still struggles due to antenna size.
In my experience, for people doing significant outdoor stuff like backpacking, endurance running, etc, a positioning device from a solid company like Garmin is going to be a good bit better than an apple, Samsung, Google, etc device.
Does the Android OS and apps like Google maps actually use multiple frequencies to get a position fix? I have friends with Samsung phones supporting dual frequency gps yet the GPS accuracy doesn't seem any better than single frequency devices.
It's transparent to the apps, it's included in all GPS (or technically GNSS) locations. GPSTest has a built in accuracy test mode where to can measure your phones location accuracy. Read more about that here: https://barbeau.medium.com/measuring-gnss-accuracy-on-androi...
I noticed a huge difference when I switched from my older phone to my current with dual frequency, and I usually log runs, walks, and bike rides so it's easy to compare the tracks. But maybe my old phone was just bad, my Garmin watch uses single frequency and it's usually quite good anyway. I've seen a few reviews of new Garmin watches and there dual frequency seems to make a small and not always noticeable difference.
They might not notice a huge difference depending on where they use location services. The real accuracy advantage of dual-frequency GPS only become apparent in degraded signal environments, such as next to tall buildings (multipath signal reflections) and under tree canopies. With a clear view of the sky, regular GPS is already quite accurate (especially if the device also supports other GNSS constellations).
The first GPS device I used didn't have any built in maps, only a breadcrumb trail on a monochrome LCD display. It used AA batteries and it was before selective availability was turned off, so accuracy was quite poor compared to today. Late -90s, so around 25 years ago now. If I recall correctly it was a Garmin 38.
Garmin devices have supported downloading satellite ephemeris data from the Internet for several product generations. This greatly accelerates getting a GPS fix. Some models will also get an approximate location via Bluetooth from a paired cell phone.
Long fix times are still an issue today with cameras that lack connectivity.
I had a Garmin Forerunner (I can’t remember the number, 425 maybe?) circa 2007. IIRC it was one of the earliest on-wrist GPS devices Garmin did. Most of the time it would only take a minute. There would be occasions where it took much much longer. Increasingly so by the time I retired in 2018.
My iPhone 13 is rather disappointing in this regard. Even in my garden, with a clear sky, Maps.app will show my location at least 5 m off my actual position.
So my 2 year old Android device already had a feature that was only now implemented by Apple in their top of the line products. Neat.
Does anyone have personal experience of how dual-frequency improves GPS? As I'm not really using GPS a lot, I'm not sure I noticed a difference from my previous devices (I live in EU, so also no high rise skyscrapers here)
I doesn't matter if your device had it for 99999 years and is therefore 'way cooler', what matters is how far along the GPS satellites are, and at this stage there isn't even one complete deployment, it's still being deployed.
Android has copy and paste before iOS but you wouldn’t want to brag about it just because. It didn’t work well at all till iOS came out with their implementation
"Neat" but if it isn't even noticeable to you, the end user, then perhaps that's why Apple waited. After all, it would require die space, antenna and power.
Though the table could use an update, I've tried to add new devices I got my hands on because (conversely) I'd like to know the accuracy of a device before buying it with mapping in mind.
What I found interesting is that
> As of 2021, some recent smartphones claim to support Galileo but in fact do not work with it. This includes the Fairphone 3 and 3+; Motorola Moto G Power and Moto G30. On the other hand, the Xiaomi Mi A2 Lite does not claim Galileo support (including on the manufacturer's own page), yet it works. The Samsung S10e is also confirmed to work.
The spec sheet doesn't always match reality unfortunately (or, for Xiaomi, fortunately!).
Most phones since 2013 or so for GLONASS, and most after 2017 or so for GALILEO, at least in the US. These constellations needed US approval to be allowed as supplemental data, and it still requires an initial lock to GPS before feeding them in. GLONASS is only one of the constellations not broadcasting a civilian second band.
Additionally, Beidou is still banned and blocked in firmware while in US even though the satellites are broadcasting, since this constellation lacks US approval (partially because the other constellations are 1-way systems broadcasting to receiver and Beidou is a two-way system, that can be used for tracking and likely emergency response). Here's some slides about BeiDou's technical details, specifically note the 2-way messaging since all anyone's been talking about is Spacex/Globalstar: https://www.gps.gov/cgsic/meetings/2020/geng.pdf
They do more than just average the systems - they can use information from one to get a lock on satellites from another, they can in some cases use just one or two satellites from a system even when a lock requires 4 or more satellites.
Considered that I follow hardware development fairly closely, I didn't even know this was not a thing on iPhone. And now Apple is making a big deal about it.
Could anyone shares any thoughts as to why Apple only include it now? And not earlier?
Does anyone here have any insights or opinions on L5 only navigation? oneNav seems to think it's better than L1+L5, citing lower complexity and power usage, but with maintained accuracy. Sounds too good to be true, will devices skip the L1 band eventually?
GPS assumes* light travels in a straight line, which it doesn't due to atmospheric effects and reflections off buildings. L5 is a second frequency from the same satellites, which is affected by these problems differently, so the chip can compare the differences between the two signals and guess what's up with the atmosphere and buildings / throw out the dumber looking signal. It's also mostly independent so it's more data. L5 is also a bit less affected by atmosphere inherently.
The upshot is much better accuracy in urban canyons, and a small improvement where GPS was already good.
* Obviously people making chips and apps know this and try to mitigate it.
I’ve anecdotally found that GPS is much worse in dense cities like New York than in sparse ones like Tucson. Hopefully my next phone will give me better location results.
The short of it is that for the past two decade or so the us govt has been rolling out a new signal that the latest series of GPS satellites transmit that uses 1. more bandwidth, 2. more transmit power, 3. in a protected region of spectrum, 4. using modern encodings and error correction. This makes it a lot easier to pick up the signal from noisy environments.
Honest concern: how do we know that Apple isn't going to secretly share this data anyone who asks for it politely? I know they've been very good at maintaining privacy-first appearance, but where is too much good stuff a bad combo?
Seriously though, I love iPhones as the next guy, and find them very convenient, but are we trading convenience for carrying an unbound GPS tracker in every pocket, and if so, how do we change course? Is it even possible these days to unsubscribe from Apple/Google without feeling like one's living back in the stone age?
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Garmin has recently released several watches with it as well, both their high end models and some more affordable ones. They also have an auto mode that switches it on or off depending on if the current environment needs it, to save power when you can have the same accuracy without it.
Personally, I find the accuracy and sensitivity of modern GNSS devices amazing. I remember when you had to wait maybe 10 minutes to acquire a fix, the accuracy was poor and maybe within 10 meters, and if you covered the receiver with clothing you would lose satellite fix. Now my phone gets a good position in a few seconds, I can see which side of the road I ran on, and even with my phone in my pocket I can often get a reasonably accurate track indoors.
https://www.androidauthority.com/dual-frequency-gps-878169/
https://play.google.com/store/apps/details?id=com.android.gp...
* Ephemeris and almanac data updated via the internet so the receiver doesn't have to wait for either and can immediately know what satellites to listen for and acquire.
* Precise clock via NTP so the receiver has a smaller solve space for its internal clock
* AGPS gives a very good position fix to further help with the initial clock and position solving
L5 support has been available in a number of devices for a couple of years now. Garmin was one of the first to use L5 in commercial devices, with their Fenix watches a while back.
The phone I'm currently using, the Pixel 6 Pro uses the L5 band. It's nice and I can definitely tell a difference, but it still struggles due to antenna size.
In my experience, for people doing significant outdoor stuff like backpacking, endurance running, etc, a positioning device from a solid company like Garmin is going to be a good bit better than an apple, Samsung, Google, etc device.
I noticed a huge difference when I switched from my older phone to my current with dual frequency, and I usually log runs, walks, and bike rides so it's easy to compare the tracks. But maybe my old phone was just bad, my Garmin watch uses single frequency and it's usually quite good anyway. I've seen a few reviews of new Garmin watches and there dual frequency seems to make a small and not always noticeable difference.
Long fix times are still an issue today with cameras that lack connectivity.
Dead Comment
It says that GPS has added a new band (L5) that works better indoors. Combining it with traditional L1 gives better results. L5 is not fully deployed.
A totally excellent list of supported and tested devices is at the latter part of this article.
https://barbeau.medium.com/tl-dr-dual-frequency-gnss-on-andr...
Deleted Comment
My iPhone 13 is rather disappointing in this regard. Even in my garden, with a clear sky, Maps.app will show my location at least 5 m off my actual position.
Dead Comment
Does anyone have personal experience of how dual-frequency improves GPS? As I'm not really using GPS a lot, I'm not sure I noticed a difference from my previous devices (I live in EU, so also no high rise skyscrapers here)
Though the table could use an update, I've tried to add new devices I got my hands on because (conversely) I'd like to know the accuracy of a device before buying it with mapping in mind.
What I found interesting is that
> As of 2021, some recent smartphones claim to support Galileo but in fact do not work with it. This includes the Fairphone 3 and 3+; Motorola Moto G Power and Moto G30. On the other hand, the Xiaomi Mi A2 Lite does not claim Galileo support (including on the manufacturer's own page), yet it works. The Samsung S10e is also confirmed to work.
The spec sheet doesn't always match reality unfortunately (or, for Xiaomi, fortunately!).
Additionally, Beidou is still banned and blocked in firmware while in US even though the satellites are broadcasting, since this constellation lacks US approval (partially because the other constellations are 1-way systems broadcasting to receiver and Beidou is a two-way system, that can be used for tracking and likely emergency response). Here's some slides about BeiDou's technical details, specifically note the 2-way messaging since all anyone's been talking about is Spacex/Globalstar: https://www.gps.gov/cgsic/meetings/2020/geng.pdf
Could anyone shares any thoughts as to why Apple only include it now? And not earlier?
https://onenav.ai/solution/
The upshot is much better accuracy in urban canyons, and a small improvement where GPS was already good.
* Obviously people making chips and apps know this and try to mitigate it.
Seriously though, I love iPhones as the next guy, and find them very convenient, but are we trading convenience for carrying an unbound GPS tracker in every pocket, and if so, how do we change course? Is it even possible these days to unsubscribe from Apple/Google without feeling like one's living back in the stone age?