smartphone GNSS, with L1 + L5

[Lodro Gyamtso]

Hi Sean,

it was september of 2017, when we read into the press, a message of Broadcomm about new mobile GNSS chip with ability of 2 GNSS frequency. Of course, some of us knows very well, this has to do, ONLY for civilian use. The military and some special people has this capabilities a lot of decades before. From my poor experiance I knew from 2014 the model Trimble R10 for professional use. So, smartphone or military or special people has access to different accuracy.

When I read this news, I visit  Broadcomm web page for more information. I found this info, BCM4775X family it was the ONLY alive production chips and the previously model BCM4774 (into samsung s8) was at the end of production.
As we know from other manufacturers like Intel + AMD or Nvidia + ATI, they produce 3-4 chip families (for price level) . Every family has once again, 3-4 models with disable inside capabilities for differend price level. This help to keep down the manufacture cost.
If I am right to this theory, Samsung forced to use BCM47752 (model BCM4774 has no stock) and no reason to pay more for BCM47755, it is so early for this technology into the customers smartphone. There was not any market competition at this moment.


What we need to have, if we need to work with 2 GNSS frequency. 4 collaborations are needed so that the consumer has the expected results

1a. satellites into the sky
1b. not only from GPS, also from Glonass, Galileo, Beidu
some text from this link www.gps.gov/systems/gps/modernization/civilsignals
"Most of the new signals will be of limited use until they are broadcast from 18 to 24 satellites."
"In 2009, the Air Force successfully broadcast an experimental L5 signal on the GPS IIR-20(M) satellite. The first GPS IIF satellite with a full L5 transmitter launched in May 2010."
"In April 2014, the Air Force began broadcasting civil navigation (CNAV) messages on the L5 signal. However, L5 remains pre-operational and should be employed at the user's own risk until it is declared operational."

2. devices (hardware) must have GNSS receivers with this ability
- today there ONLY 1 smartphone into the market. But with no proof that this feature is working as it should be
- when we are using 2 frequencies, battery consumption is higher

3. android support (operating system)
text from this link https://forum.xda-developers.com/showpost.php?p=76488010&postcount=128
"L5 signals should be visible in GPSTest if the hardware supports it and the device has Android O or later"
Android 9 will have hidden this feature, it's ONLY for developers. So, when everything goes OK, Google will release this specs into next android, the 10 version. Please wait for 1-2 years more

4. when all the rest are OK, navigation software must updated
sygic, tomtom, here, locus maps, etc



https://forum.xda-developers.com/showpost.php?p=76785866&postcount=169
I would     like to answer to this message
The follow smartphone is using uBlox generation 8. Maybe and others. Soon or late there will be a new model with updated specs. But who can spend 1500$ to buy it ????
MobileMapper 50
http://trl.trimble.com/docushare/dsweb/Get/Document-822185/MM50_Android_UserGuide.pdf
page 49
The MobileMapper 50 handheld contain an integrated uBlox Neo-M8T GNSS receiver


https://medium.com/@sjbarbeau/dual-frequency-gnss-on-android-devices-152b8826e1c
into this page, we can find the Xiaomi mi8 news. There is one screenshot from gps test measurements. What is this ???? ONLY 16 meters accuracy ??? what a shame that's terrible.
If we also see the follow video, at this time section 11:03 - 11:59
we can proof the poor GNSS receiver measurements. It has also 16meters accuracy.
https://www.youtube.com/watch?v=BwbRpkUhVFE

[Sean Barbeau]

Yes, the intro of dual frequency into the market hasn't been the smoothest yet, but hopefully things will improve as OEMs get used to the BCM47755 and other chipset become available. 

Also, regarding accuracy:

Note that the accuracy value shown in apps usually comes from the Location.getAccuracy() Android API which has the following definition:

Get the estimated horizontal accuracy of this location, radial, in meters.

We define horizontal accuracy as the radius of 68% confidence. In other words, if you draw a circle centered at this location's latitude and longitude, and with a radius equal to the accuracy, then there is a 68% probability that the true location is inside the circle...

So, the position calculated by the GNSS could have an estimated accuracy of 16 meters (which is what is shown in the app), but a true accuracy of much less than that (even the cm level). You don't know what the true accuracy is unless you give the phone a ground truth value to calculate the actual error against. Obviously, you need to set the ground truth value as close to your actual position as possible, ideally somewhere that has a surveyed latitude and longitude.

I believe the GNSSLogger app has a mode to calculate actual horizontal error, as does another app that I maintain - GPS Benchmark:

https://play.google.com/store/apps/d...chmark.android

I'd like to see benchmarked accuracy from one of these apps before passing judgement on true accuracy. 

Sean

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[Lodro Gyamtso]

Xiaomi Mi 8 Dual Frequency GPS Better Than Others Or Marketing Hype?

https://www.youtube.com/watch?v=ZTEXJHR4tOA

[Sean Barbeau]

Thanks for sharing! I'm glad the people are continuing to give the Mi 8 a hard look when it comes to dual frequency. 

The issue with using general purpose apps to record paths for the purpose of evaluating GNSS is you don't actually know which positioning technology is being used. Google encourages all app developers to used the "fused" Location provider in app, and this method uses a lot of other data in addition to GNSS to "fuse" and a position. You'll need to use a special purpose app that specifically listens to GNSS only (GPS Benchmark, GnssLogger) to look specifically at GNSS accuracy. 

That being said, if you're more concerned with how good the general location accuracy of the phone is for apps like Google Maps, then using apps like Google Fit could give you an idea of that. So, the comparison in the video here seems to indicate that currently overall location accuracy for a hike outdoors is pretty close to other flagships. 

On Sat, Jun 30, 2018, 5:08 PM Lodro Gyamtso <lodrog...@gmail.com> wrote:

Xiaomi Mi 8 Dual Frequency GPS Better Than Others Or Marketing Hype?

https://www.youtube.com/watch?v=ZTEXJHR4tOA

--

[Lodro Gyamtso]

Spectra Precision SP20

It was July 9 of 2018 and Spectra Precision (a Trimble company) announced the latest state-of-the-art device, with high performance GNSS receiver having centimeter accuracy.

Why I am repeat this info? Because this professional device (also expensive) can support 3 frequencies, L1 - L2/B2 - E5.

How big is this device ? It's 5.3 inch only, into a hard plastic case with external GNSS antenna. YES, it use external antenna to succeeds this results.
The truth is, It's a Android 6.0 smartphone with the SoC of Qualcomm snapdragon 410. And of course this old hardware and operating system can collaborates with the embedded special GNSS receiver of 240 channels and 6 GNSS systems.

product announced
http://www.spectraprecision.com/eng/spectra-precision-introduces-the-sp20-handheld-gnss-receiver-with-innovative-camera-enabled-centimeter-logging

product link
http://www.spectraprecision.com/eng/sp20-gnss-handheld.html

brochure
http://www.spectraprecision.com/media/custom/upload/File-1530705167.pdf

manufacture video
https://www.youtube.com/watch?v=hRZ2zOQWMLM

[Lodro Gyamtso]

I would like to continue to my previous post and add my personal thoughts.

Why we must buy a new device and pay a lot of hundreds of dollars for a new hardware and operating system like Xiaomi Mi8 ??? What a new smartphone needs for centimeter accuracy ?
The answer is .... It use ONLY a new GPS module (GNSS I like most to say). In this example it use the latest Broadcom BCM47755.

So, what if we have a small plastic box in our pocket (dimensions like a Nokia 150) with a
- 1200mAh battery
- bluetooth interface
- and of course the U-blox F9 module or Broadcom BCM47755 or similar GNSS receiver

In what cost ???? from 80-120 dollars ....
Yes, that could be the world cheaper answer to all the consumers who don't like to be foolish, from the smartphone manufacturer companies

For example, you can see this video. It's from the previous U-blox 8 module. See how easy is all the project. And don't afraid, the end user (customer) will buy one "ready to use" product "out the box". This video is only a experiment project.
https://www.youtube.com/watch?v=FmdG66kTfsI

[Lodro Gyamtso]

Hi,

before some days (29/09/2018), one German site make a new review for the public. As always, the review is very detail. If we go to GNSS section, we can see how this very promising "dual frequency" device, which is the first all over the world, has fail to the costumers GNSS community.

-the follow text is from the article to proof what I am saying to this post. It's not my opinion, I transfer the facts
but we expected more from a dual-GPS device. Maybe future updates will bring greater GPS accuracy

review link
https://www.notebookcheck.net/Xiaomi-Mi-8-Explorer-Edition-Smartphone-Review.336456.0.html

[Lodro Gyamtso]

I have found another review of Xiaomi Mi 8, compared with 2 Garmin devices. Once again the accuracy is still bad. Obviously this also affects the recording of the route, with the result that we have only a few times a straight line to ours recording track

link
https://www.navigation-professionell.de/en/xiaomi-mi-8-review-gps-galileo-accuracy/

[Lodro Gyamtso]

post 5
My Mi8 also never went below 4m while I am outside and just walking the street. Below 4 only happened after i started driving the car, which is bizarre, maybe it is the way it sweeps the signals. Don't know.


review link
http://en.miui.com/thread-3427566-1-1.html

[Sean Barbeau]

Definitely don't trust the "H/V Acc" field as an accurate representation of position accuracy.  This is provided by the GNSS implementation and in the past on other devices has been notorious for being inaccurate.

For example, horizontal accuracy comes from Location.getAccuracy():

https://developer.android.com/reference/android/location/Location.html#getAccuracy()

...which says:

We define horizontal accuracy as the radius of 68% confidence. In other words, if you draw a circle centered at this location's latitude and longitude, and with a radius equal to the accuracy, then there is a 68% probability that the true location is inside the circle.

That means that there is a 32% chance that the true location is OUTSIDE the circle, which isn't great.  In those cases the value may read "4 meters" but the true value could be much larger than that.

The best way to measure accuracy is using an app that allows you to benchmark accuracy against a ground truth location entered by the user (for example, my old GPS Benchmark app - https://play.google.com/store/apps/details?id=com.gpsbenchmark.android), or another method of doing a controlled test.

The best tests I've seen so far are in the attached presentation from ION GNSS.  The below screenshot is slide 12, which shows some aerial imagery and the Mi 8 data compared to the Samsung S8.  The S8 is older GNSS hardware (2015) so the improved accuracy here may not be entirely from dual frequency, but the Mi 8 does perform better.

Sean

[Sean Barbeau]

For some reason the screenshot didn't come through in the last post.  I've attached it here.

[Lodro Gyamtso]

Hi Sean,
of course it seems logical, every new technologies to be improved compared with old models (designs).

But when we read the review to the previous post from date (Oct 5 2018), into the German site we can find the follow text ...
The GPSMAP 64s accuracy is a tad better
how is this possible ? with one handheld PND device, to a 2/3 of the price of Xiaomi Mi8, with ONLY L1 frequency support, with 3 meters accuracy (into Garmin satellites/dashboard menu) compared with the promised accuracy of 30cm of Xiaomi Mi8 with L1+L5 ?

Probably there are others reasons about that.
Some device vendors do a better job at optimizing their GNSS design (e.g. GNSS antenna, RF path, antenna isolation between GNSS and WWAN and WiFi/BT etc.)
this answer is from one email I received from qualcomm, 2 years ago
For me this the only reason (hardware design), why the static accuracy compared or/and the recording track into a navigation device, has this results.

[Lodro Gyamtso]

Xiaomi Mi Mix 3

according to gsmarena this new device support

dual band GPS/Galileo, also single-band GLONASS/Beidou

review link

https://www.gsmarena.com/xiaomi_mi_mix_3_handson-review-1844.php

[Sean Barbeau]

Thanks for sharing!  I added it to the bottom of my article:

https://medium.com/@sjbarbeau/dual-frequency-gnss-on-android-devices-152b8826e1c

Sean

--

[Lodro Gyamtso]

Huawei Mate 20 Pro

I have found one review for this device into German language
www.notebookcheck.com/Test-Huawei-Mate-20-Pro-Smartphone.337772.0.html

I hope soon, there will be a smartphone review using dual frequencies (L1 + L5), having better accuracy and track recording compared to Garmin devices with only L1 signals.
And something else.  What will be into near feature, if Garmin decide to release new PND models with dual frequencies (L1 + L5) ? No more smartphone devices for the enthusiast of navigation ?

[Lodro Gyamtso]

Huawei Mate 20 Pro

today I had the luck to test this device (for free) with the help of one retail shop. I made 2 tests using the GPSTest app, one indoor and one outdoor of the shop. Both of them was made without stoping the app of running. All of test was made in static conditions (pedestrian - no movemend)

indoor
- the device was into demo stand, with power cord and anti-theft capabilities
- into 4 seconds there was location found
- satellites was 24/34
- H/V Acc : 4.0/0.0m
- C/NO : less of 30
- C/F : EMPTY
- ID : there was ONLY unique numbers / flag
- no SBAS

outdoor
- satellites was 27/34
- H/V Acc : 4.0/0.0m
- C/NO : some of them was over 40
- C/F : EMPTY
- ID : there was ONLY unique numbers / flag
- no SBAS

[Lodro Gyamtso]

Snapdragon 855 Mobile Platform

according to manufacture site, this new SoC has "Dual frequency GNSS". This new ability for qualcomm chips is internal the SoC, not like Xiaomi and Huawei smartphone models they are using one more chip (from broadcom) to add "Dual frequency GNSS" to the device capabilities. I believe, soon or late, this feature will pass to the mid and low end SoC of the company.

text from qualcomm site

Location

Satellite Systems Support: GPS, GLONASS, Beidou, Galileo, QZSS, SBAS, Dual frequency GNSS

links

site

https://www.qualcomm.com/products/snapdragon-855-mobile-platform

Product Brief

https://www.qualcomm.com/media/documents/files/snapdragon-855-mobile-platform-product-brief.pdf

[Sean Barbeau]

Lodro,

You beat me to it! :)

I read some of the press coverage yesterday but no one had mentioned dual-frequency GNSS.  I had it on my TODO list to check the actual specs today - so that's a welcome suprise!

I've updated my dual-frequency GNSS article to include the Snapdragon 855 (under Galaxy S10 section):

https://medium.com/@sjbarbeau/dual-frequency-gnss-on-android-devices-152b8826e1c

Sean

[Lodro Gyamtso]

Hi Sean,
maybe this has to do because my country has GMT time +2 ???

It's very strange, for those who saw the presentation of Qualcomm last days, there was not any reference to this NEW capability into the SoC. They spend too many time for the 5G modem ...
In the other hand, last year the competitors have succeeded to inform the people for the next step of technology into the navigation. I am talking about ST Microelectronics, u-blox and Broadcom.

Unfortunately we have to wait until the 4-6 month of 2019, when the new devices with 855 appear in the stores. Only then we can see if this solution is working as it should be. I am saying this because the other competition with Broadcom has failed (for now) to his promises to the buyers.

[Lodro Gyamtso]

I want to remind to users with android 9 devices and also with hardware support for dual frequencies for GNSS receivers, to look for the follow setting.  It's inside "developers menu". I don't know how this option affects the measurements results (I don't own a device with this capabilities), but you should give it a try

[Sean Barbeau]

The official statement from Google is that this setting should turn off duty cycling to allow carrier-phase measurements (applicable to single or dual frequency), but I don't know if it has any other effect.

Sean

On Sun, Jan 27, 2019 at 12:47 PM Lodro Gyamtso <lodrog...@gmail.com> wrote:

I want to remind to users with android 9 devices and also with hardware support for dual frequencies for GNSS receivers, to look for the follow setting.  It's inside "developers menu". I don't know how this option affects the measurements results (I don't own a device with this capabilities), but you should give it a try

--

[Lodro Gyamtso]

screenshot from Xiaomi Mi8

[Lodro Gyamtso]

Xiaomi Mi 9 is one device with the Snapdragon 855 SoC. This SoC has internal support for dual band GNSS signals. There no extra info if this product use the internal GNSS receiver or the external Broadcom GNSS receiver as like Xiaomi Mi 8 did last year.

Into this first review, we can see and hear from time 10:36 at the follow video
- static accuracy from 3-5 meters
- there are double id's 25,26,32 from GPS (USA)

video link
www.youtube.com/watch?v=tp1wFof8ZfM

[Lodro Gyamtso]

we have a new video for Xiaomi Mi 9. This time the reviewer is using the app GPSTest from Sean Barbeau.

video link
www.youtube.com/watch?v=C3GZUFZQPUk
time 3:14

P.S.
the CF for Glonass has issue ???

[Sean Barbeau]

Very cool! Thanks for sharing.

Yeah, strange, looks like the CF for GLONASS isn't being recognized. I can't see the value in the video but hopefully someone will share a screenshot soon. 

Sean

--

[Lodro Gyamtso]

1575.420

[Sean Barbeau]

Oh, looks like this is the new GLONASS CDMA L1 signal, as mentioned in:

https://gssc.esa.int/navipedia/index.php/GLONASS_Future_and_Evolutions

I've opened an issue to add support in GPSTest:

https://github.com/barbeau/gpstest/issues/264

Thanks for taking the screen grab!

Sean

[Lodro Gyamtso]

Hi Sean,
what do you think about a new ability to GPSTest app. Some how, the user can see the

- Coding
CDMA
FDMA

- Frequency
1.563–1.587 GHz (L1)
1.215–1.2396 GHz (L2)
1.164–1.189 GHz (L5)

- something else ???

without the need of android studio, real time into the field. Maybe with a new screen or one hidden menu or multi tap the screen or ....

[Lodro Gyamtso]

                                                                                                click to see into full size
Samsung Galaxy S10

as we all know there are to versions, one with 855 SoC and one with 9820 SoC. I have found the teardown of European model with 9820 SoC. Unfortunately we can see the Broadcom BCM47752, the same as we can found into the previous model Samsung Galaxy S9.
When we read the text into the web page of this site, there is "Broadcom is onboard with its BCM47753K0BIG GNSS receiver"

According to Broadcom page info or pdf manual there is no BCM47753 chip. I hope this is a typo error from the site of teardown and the real chip is the BCM47755

site of teardown
www.chiprebel.com/galaxy-s10-teardown/

[Lodro Gyamtso]

Samsung Galaxy S10

it seems we have to wait one more year to see (???) dual band GNSS support from Samsung flagship models ....

[Lodro Gyamtso]

click images to see into full size

Xiaomi Mi 8

review link

www.notebookcheck.net/Xiaomi-Mi-8-Smartphone-Review.413848.0.html

this model was the first smartphone ever, to support dual band GNSS. Up today, there a lot of enthusiast people they pay a lot of money to see with GPSTest application the L1 + L5 signals. But for what reason ? If there is no "cm accuracy" why to lose our money ??? And for not only this model !!!

[Sean Barbeau]

what do you think about a new ability to GPSTest app. Some how, the user can see the
- Coding
CDMA
FDMA
- Frequency
1.563–1.587 GHz (L1)
1.215–1.2396 GHz (L2)
1.164–1.189 GHz (L5)

Yes, I'll need to address this somehow as part of https://github.com/barbeau/gpstest/issues/264.

[Joop van der Velden]

Hi guys,

I was wondering if the Qualcomm 855 spec of "dual frequency" is really meant to be Dual Band (L1 + L5, or upper and lower L band), 

or simply the 2 different frequency's on which Glonass and GPS/Galileo operate within the upper L1 range?  (1560 - 1610MHz) 

See the frequency graph at https://gssc.esa.int/navipedia/index.php/File:GNSS_navigational_frequency_bands.png

Anybody who can clarify this?

Op maandag 18 maart 2019 17:26:50 UTC+1 schreef Sean Barbeau:

[Joop van der Velden]

Oh, after some more reading i can answer my own question...:)

Appearantly the 855 soc  really is dual band gps reception.

Op dinsdag 19 maart 2019 12:41:17 UTC+1 schreef Joop van der Velden:

[Lodro Gyamtso]

Samsung Galaxy S10 - Exynos 9820

text from the site review

The S10 uses BeiDou, GLONASS, and GPS for location services just like the Galaxy S10+. Unfortunately, it does not support SBAS or dual-GPS as the Mate 20 Pro does, which can improve location accuracy. Our review unit found a satellite fix quickly and accurately both indoors and outdoors. The device achieved a sat fix with up to 6 metres accuracy outdoors and 8 metres indoors, but generally took a few seconds to pinpoint our location having found a satellite to which it could connect.

review link
https://www.notebookcheck.net/Samsung-Galaxy-S10-Smartphone-Review.414549.0.html

[Lodro Gyamtso]

                                                                                                         click to see into full size

into the theory of electronics, when we want to receive (or transmit) one frequency, we need into the input of our device, a component which is called "antenna".

This BIG area of frequencies is separated into small areas, calling "bands". Unfortunately for all of us, every band accordingly to wave length needs a dedicated antenna, as for the frequency to serve.

Into ours category the same theory exist. As you can see into the picture I have , this is one example (construction) of a dual band antenna, before the GNSS signals get into the receiver chip.

That's why I don't believe over 1 year now, when I read into various forums, people who are discussing that when the change the "GPS.xml file" to devices like Samsung S9 or S10 with Broadcom BCM47752, they can manage fool the manufacture and the device receive "multi band" signals.

[Lodro Gyamtso]

Huawei P30 Pro Smartphone Review

 

The P30 Pro supports BeiDou, Galileo, GLONASS, GNSS and GPS for location services. We could not test whether the device supports SBAS though. It is worth noting that the P30 Pro supports dual GPS when being used in North America or Europe.

Our review unit finds a satellite fix quickly even when being used in buildings, which is impressive. The device can find a fix with up to 4 metres accuracy regardless of where it is being used, although we noticed that its accuracy fluctuated more indoors than it did outdoors.

We also subjected the P30 Pro to a short bike ride to test its location accuracy against our trusty Garmin Edge 500 bike computer. The two devices plotted us having travelled almost the same distance, with the P30 Pro claiming we cycled 50 metres further than the Garmin did. The two devices recorded roughly the same altitude information too, although our review unit tracked us more accurately overall, in our opinion. In short, the P30 Pro is ideal for all general navigation tasks and even as an alternative to a bike computer too.

for full review read the link
www.notebookcheck.net/Huawei-P30-Pro-Smartphone-Review.415336.0.html

[Lodro Gyamtso]

as we can see this is probably a type error from the author of review
 

[vitob...@gmail.com]

This is my test with Huawei P30 Pro

In open sky there are a lot of satellites

If possible I ask two feature:

Lat/Long in DMS needs more accuracy to display seconds with decimal units;

Project Lat/Long into UTM also.

[Lodro Gyamtso]

when I carefully observed the photos in the previous post about the Huawei P30 Pro device, I found that
- navstar system has only 4 working satellites per hemisphere around the earth
- galileo system has only 6 working satellites per hemisphere around the earth

as we all know, a full operating GNSS system need 12 satellites. Don't forget this, when you will buy a device with dual band support.

[Lodro Gyamtso]

I mean ... per hemisphere around the earth

[Sean Barbeau]

Thanks for the screenshots!

Re: additional formats, there is an open issue here:

https://github.com/barbeau/gpstest/issues/242

Sean

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[gpsfan]

Great group and great topic !

Trying to sum up the smartphones that have L1/L5 support shown in GPSTest at this point, it seems we have

- Xiaomi MI8 - QC845 with BCM47755

- Xiaomi Mi Mix 3 - QC845 with BCM47755

- Huawei P30 Pro - using native QC 855 dual band support ?

In theory the Xiaomi Mi9 with QC855 should work too but GPSTest does not show L1/L5 support ?

[Lodro Gyamtso]

on 20/4, qualcomm announced the SoC 735. Into the specs (picture) we can see it has "iZat 9", just like the SoC 855. So, it's logical for us to suppose it will have "dual band GNSS". If this is true, now we can have "dual band" GNSS into mid-range price level of smartphone. And the next step is this to continue into the other series of low-end SoC.
For the moment there is no official announcement about the thoughts i made, so we must hold our happy.

Please, don't confuse the multi band support with the "cm accuracy". Qualcomm has never official announcement "cm accuracy" for iZat technology it has.

[Lodro Gyamtso]

who many GNSS channels mush have a modern dual band smartphone device

- GNSS receiver channels per hemisphere
GPS L1+L5 = 12+12 = 24
GALILEO E1+E5 = 12+12 = 24
QZSS (local system) L1+L5 = 4+4 = 8
GLONASS 12
BEIDOU 12
SBAS 3 (more all less)

24+24+8+12+12+3 = 83 at least

there are times i have saw into my device 15 satellites into GPS system or 16 satellites of Beidou system. Not always, but periodically

[gpsfan]

That's good news if Dual-Band is coming to the QC735, still it seems that the phone makers need to add the proper software/hooks/interface for dual-band to work since all the QC855 phones (like the Mi9 apparently) don't show L1/L5 in GPSTest.

Do you agree with my list above of phones currently showing L1/L5 with GPSTest ?

[Lodro Gyamtso]

about dual band smartphone devices
- i think Android 10 it will ready to full support this new feature. With version 9, google - manufactures - sw developers, all of them, do there own tests before they supply end users (customers)

about satellites
- Galileo will full operate at year 2020+
- Navstar (GPS) will full operate at year 2022+

about your list
- please answer what do you mean ?
1. it's your favorite list ?
 or
2. what's into the market for all of us ?

why you are searching for a dual band smartphone device ? what it will be the profit for you using this new feature ?

[gpsfan]

Yes, what's available on the market right now for all of us. Judging by your answer it seems I may have forgotten a few ;-)

[Lodro Gyamtso]

searching GSMarena or manufactures web pages, this list support dual band GNSS. Maybe every device with those GNSS chips could able to have the same features, but .... ???

GNSS chip Broadcom 47755
 Xiaomi
- Mi 8
- Mi 8 Pro
- Mi 8 Explorer Edition
- Mi Mix 3

GNSS chip Kirin 980
Huawei
- Mate 20
- Mate 20 Pro
- Mate 20 X
- Mate 20 RS Porsche Design
- Huawei P30 Pro
- Huawei P30

Honor
- View 20
- Magic 2
- Magic 2 3D

GNSS chip Snapdragon 855
Xiaomi
- Mi 9
- Mi 9 Explorer

Samsung regional USA/LATAM, China
- S10e
- S10
- S10+

[gpsfan]

Thanks for the list, I guess I wasn't clear in what I was trying to do, i.e. list out the current smartphones that are confirmed to show L1/L5 in GPSTest (and therefore properly configured by the manufacturer for all apps that use GPS) and AFAIK it's the only 3 that I'd listed but I may have missed others ?

[Lodro Gyamtso]

one new model has added at list to support dual band GNSS.

GNSS chip Snapdragon 855
Oppo
- Reno 10x zoom

[Lodro Gyamtso]

OnePlus 7 Pro Smartphone Review

www.notebookcheck.net/OnePlus-7-Pro-Smartphone-Review.420598.0.html

text from review site

The 7 Pro uses BeiDou, dual-channel Galileo, GLONASS, dual-channel GPS including A-GPS and SBAS for location services. These allow our review unit to achieve a satellite fix with up to 6 metres accuracy outdoors, which is comparatively inaccurate for a flagship smartphone.

what can we say for this accuracy ??? I hope there is a bad measurement

 

[Joop van der Velden]

Lenovo Z6 can also be added

https://www.gizmochina.com/2019/05/13/lenovo-z6-pro-youth-edition-gps-accuracy/

Lenovo Z6 Pro Youth Edition to have GPS positioning accuracy of 1m

Op dinsdag 23 april 2019 09:50:27 UTC+2 schreef Lodro Gyamtso:

[Lodro Gyamtso]

Lenovo Z6

i just read this article, from previous post. The review is using GPS Test from Chartcross Limited. With this app we can not see decimal digit after the value of meters. So, we can not be sure if the measurement will be 0.6 meters or 1.4 meters. With this working theory the app will show 2 meters when the real value will from 1.5 - 2.4 meters.

Any way, 1 meter into the screen, it is better from others competitions with 6 meters. And of course not only this is happening here. The measurement is NOT static, is when we are in movement, maybe with car, i believe. See the picture and read the text below ...

With this, the accuracy level of positioning reaches 1m level. The “57” in the lower right corner shows that the test conducted at a speed of 57 km/h and also reveals that it is not in a stationary state.

 

[gpsfan]

But that's just "theoretical" accuracy, not the "real" accuracy that you can determine with the beta version of GPSTest using a known good position.

[Lodro Gyamtso]

Sorry my friend, but you have confused the 2 types of accuracy. The first one is static accuracy and the second one is when we are moving - traveling. Into the previous post I was talking, this example was when a vehicle was running with 57 Km/h. What are you talking about "a known good position". This is something probably you want  for your personal needs. For the most of the people i know, they need a personal navigation device to travel from one place to another. That's why we need to know how good is the GNSS receiver accuracy for traveling conditions.

About the Lenovo Z6 Youth Edition, there is no other information about the hardware specs. Probably it will use "dual band support", but it's unknown the receiver code name. The rumors says it will be into mid-range device price. And this is good news for all us.

P.S.
if the news are real, this will be the first "bellow meter" accuracy device smartphone into the world

[Lodro Gyamtso]

Lenovo Z6 Youth Edition
news link
https://sparrowsnews.com/2019/05/21/lenovo-z6-youth-edition-specifications-announced-snapdragon-710-triple-camera/

text from link

Lenovo Z6 Youth Edition will be equipped with Qualcomm Snapdragon 710 processor, using the domestic Beidou third generation system dual-frequency high-precision positioning chip
The data shows that the HD8040 is the world’s first multi-system multi-frequency high-precision SoC chip that supports the new Beidou-3 signal system.

Allystar  HD8040
www.gpsworld.com/allystar-launches-multi-band-multi-gnss-chip-for-devices/

reading this news, we can see that we have the first smartphone into the world using Dual band of
GPS/QZSS
GALILEO
BEIDOU

[JLR]

From a Oneplus 7 Pro, (US) with 9.5.3 firmware

[Lodro Gyamtso]

                                                                                                         click image to see into large size


video link
www.youtube.com/watch?v=m-HWOoigQu4

Redmi K20 Pro

1. it support dual band

2. GPSTest shows hertz data into CF column

[Devdass Krishnan]

What is the difference between the Lenovo phone that you mention and the ones from the list above?

 

[Devdass Krishnan]

I'm also wondering about SBAS vs Dual Band. How available is SBAS technology in smartphones for a pedestrian to use?

[Devdass Krishnan]

What's the difference between the Lenovo Z6 Youth Edition and those from the list that you added above? I thought that there were other phones that uses Dual Band, no?

[Lodro Gyamtso]

I will answer with one post to all of 3 questions you have.

1. Lenovo Z6 Youth Edition is the first smartphone in the world
- dual band of 3 systems: GPS, GALILEO, BEIDOU
- the company with a video presentation, show to people that the device has 1 meter accuracy when we are moving with speeds over 60 km/h

2. for everyday driving or pedestrian use, at the city or the mountain, from one A point to the B point, we can use a smartphone device having only one band (L1) GNSS receiver of multi systems (like GPS, Glonass, etc.), at the price level of 99 dollars. Let professional people to buy an expensive device (like Trimble) to have this high price equipment for those jobs.

3. when into the future, after 5-10 years, the devices of dual band (or multi band) with multi satellites systems has low cost (100-200 dollars) prices and of course the consumers have the proofs that everything is working as like the company's marketing promises, then go and buy one new smartphone.

[gpsfan]

Where is this video presentation showing 1 meter accuracy moving at 60 kph ? Doesn't seem like it would be something very easy to prove, hope they're not just showing the "hardware accuracy" value like GPSTest does and that is just a statistical accuracy based on PDOP.

[Lodro Gyamtso]

Lenovo Z6 Youth Edition China Launch event

23:15 -31:16

https://www.youtube.com/watch?v=ZbNDJtzzl0E

[gpsfan]

Would have been nice to get a time in that 41 minute video...so here it is https://youtu.be/ZbNDJtzzl0E?t=1719 and yes that's just what GPSTest by Chartcross reports, "Hardware Accuracy" which is a theoretical accuracy based on the "geometry" of satellites used in the fix (what used to be known as PDOP and the more satellites you have the better the theoretical accuracy) and proves absolutely nothing like I've already told you.

The only way to VALIDATE these claims is comparing the GPS position reported by the device to the ACTUAL KNOWN position. Which is exactly what the beta version of Sean Barbeau's GPSTest app does. And it also compares it to the "hardware" accuracy and you'll see with the first test reports that it's (as exptected) quite different.

[Lodro Gyamtso]

as i have told you, gpsfan, i interesting for measurements when we are "in motion". if you like static measurements, it's something you have to make conversation with other people.

If you can found any other smartphone device at a cost of 160$, to have 1 meter accuracy when the car is running from 60-70 km/h, using GPS Test from Chartcross, please let us know this info. For me, it's OK

have a nice day

[gpsfan]

I'll give it a last try...you need to understand that the "accuracy" reported  by standard GPS software like GPSTest by Chartcross has no connection to REALITY, it is just a theoretical calculation likely based on PDOP so the more satellites in the fix (and dual channel systems will have a lot by design), the lower that number will be, even if it uses bounced signals (multipath). Do you really believe a smartphone behind the dash of a car can get 1 meter accuracy in downtown Manhattan ? If you do I have a few bridges available for sale ;-)

If you're serious about GPS accuracy, and I would think everyone in this group is, download Sean's GPSTest (the reason this NG exists BTW) app and do some testing. Even if you're static in downtown Manhattan (or in any urban setting with multipath) there is no way you're getting 1 meter accuracy and that app will show that very well.

[gpsfan]

SBAS is not really about accuracy, it's more about integrity in the sense that the SBAS satellites will transmit any failures in the standard GPS satellites in real time so that receivers stop using them to prevent the risk of calculating an erroneous position.

[Devdass Krishnan]

Does SBAS not significantly increase accuracy?
Are there any examples out there of smartphones using SBAS for positioning?

[DK]

Here is a screenshot I have just taken. Where I am, SBAS is in a trial phase: https://www.linz.govt.nz/data/geodetic-services/australasian-sbas-trial

Is there any way for me to find out if my phone is utilizing the SBAS corrections?

On Sunday, 9 June 2019 11:38:56 UTC+12, DK wrote:

[DK]

[Lodro Gyamtso]

Hi DK,

what is the model of your device

about SBAS read this

[Lodro Gyamtso]

I want to say once again, professional devices like Trimble or Spectra Precision, using Android platform and they having SBAS capabilities. They announce 50cm accuracy for this devices. But they cost a lot of thousand of dollars for this accuracy.

SBAS is using also into aircraft navigation.

SBAS has L1 + L5

[DK]

My device is an LG G6. I want to make an app that keeps track of which parking spot the user has parked in, but to do so reliably, one would need precision below 1m because of the size of a carpark.

I'm trying to think of all the ways to achieve this. I'm new to positioning technologies so I'm learning as I go. I was under the impression that SBAS can send corrections to a device to enable it to achieve sub meter accuracy - it doesn't seem that easy in practice. It is also essential that the user only relies on their phone and not another external dongle.

Dual Band location tracking seems promising because there is finally an example of this being achievable in the recent Lenovo smartphone. I'm wondering if I could replicate the results in my country.

[Lodro Gyamtso]

Hi DK,
i want to share with you my personal thoughts.

You want to make a project alive, but you need a hardware specification of cm accuracy, that the today's amateurs smartphone don't have. Probably you have to wait for 2 things
1. when this smartphone exits
2. when the 7.000.000.000 of possible Android users, buy there new devices
because when those 2 things happens, your app will be accepted

on more thought
Let we say that I have this cm accuracy smartphone.
Why don't we use the internal Google maps, or a good navigation software like Sygic or Tomtom Go for this purpose ?
Don't forget that the today's navigation app can do this job (store location) and of course much more.

[DK]

It don't think the application will need cm precision, I think half the width of the carpark will suffice (roughly 2.5/2 = 1.25m). I think the idea will need some physical testing to see if it is achievable with 1m precision.

Do you think the Lenovo Z6 Youth will be more accurate in China than it would be elsewhere?

Also, how far do you think we are from being able to use a smartphone with the ability to receive RTK corrections?

[Lodro Gyamtso]

into my life, i will welcome every improved and cheap technology.

1. for the present
from my personal experience, i will accept the 3 meter accuracy from L1 band smartphone devices. It will be OK to could found the car into one open area parking. And if there are side by side 2 same car models with the same color, I will chose what is mine from the license plate. The odds for something like this is rare

2. i don't believe that the beidou satellites transmit accurate signals when they are above the Asia regional and they have poor accuracy when they are above USA

3. RTK
i am using a smartphone device for navigation reasons, without sim card, into airplane mode. Signals, only from satellites. For the future, i will wait to see, what the new techologies will offer to the costumers and i will accept only what is free of charge, just like now.

[J. B.]

Samsung Galaxy S10 SM-G9730 TGY Versión Hong Kong - Snapdragon 855

Hi,
all this is very interesting
Here I put a capture of the model mentioned above S10 G9730 TGY

regards

[DK]

Hello all.

Does anyone know what the most accurate dual band smartphone is?

I've seen the screen shots from the Lenovo Z6 youth showing +-1m accuracy
https://www.gizmochina.com/2019/05/13/lenovo-z6-pro-youth-edition-gps-accuracy/

but I was wondering if anyone can support these results or have something more solid?

[Lodro Gyamtso]

Hi DK,

for me, the most accurate multi band GNSS smartphone is the Trimble TDC150

[Dean Z]

On Tuesday, June 25, 2019 at 3:46:23 AM UTC-5, Lodro Gyamtso wrote:

Hi DK,

for me, the most accurate multi band GNSS smartphone is the Trimble TDC150

Hello. Could you please say how accurate is the TDC150?

Thank you 

[Lodro Gyamtso]

Hi Dean Z,

for more detail info, you can visit trimble web page. There are all the suitable specification about this product.

except this, into my country there are 3 local distributors. All of them can present this model, and they also can rent this device for a least one week. Search into your country for local distributor

[Dean Z]

Lodro,

Yes. I know. But you said it is the most accurate for you. I am asking what accuracy you are getting, please?

[DK]

Any new news regarding the sub 1m accuracy of the Lenovo Z6 Youth?

[Joop van der Velden]

Op donderdag 27 juni 2019 18:49:04 UTC+2 schreef Dean Z:

This is not a smartphone, it is a surveying device.  It has special hardware and - with the correct subscriptions / contracts - you can use precise positioning.

Don't compare it with a smartphone with L1 + L5 capability.

[Lodro Gyamtso]

Hi Joop van der Velden,

Trimble TDC150 is 100% android smartphone, just like Hiaomi MI8 or Lenovo Z6 Youth. Those last 2 models, use additional GNSS hardware for better accuracy, just like Trimble TDC150. Of course, into the market there are too many models of android smartphone or android tablets, with very carefully design from the manufacture, for better results into navigation needs. A lot of them has also rugged construction

According how many money we can spent, we will have the best results

[Sean Barbeau]

IMHO the Trimble TDC150, while technically an Android smartphone, falls into a different category than other general-use phones.  It's a GNSS receiver first and a smartphone second, vs. other general use devices like the Xiaomi Mi 8 and Lenovo Z6 Youth that are smartphones first and GNSS receivers second.  Main factors that put it over the line for me is form factor (TDC150 has a giant external hardware bulge while other devices have GNSS integated into normal phone chipsets), Android version (it's an obvious outlier with Android 6), and price (I couldn't find an exact price, but I'm guessing well upwards of $1k USD).

Sean

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[Lodro Gyamtso]

Hi Sean,

i am glad you can "see" the model TDC150 as a android smartphone. I am agree with all of your conclusions and i add some me too.

1. into the market there are a lot of price levels. So, when some users needs into one device (like a smartphone) the best of one specification (location measurement), this device will have the right price according the technology it will use to perform as it should be.
What kind of people need or could pay for this price ? That's why, I am very confused when some amateurs android users, want to pay some hundreds of dollars and demand so great accuracy.

2. big dimension for a smartphone
of course, when we need good signal from the antenna of our device.

3. android 6
how the trimble company has managed to make one product to have mm (0.001m) accuracy with this old android ?
Is it the only one ? no, it isn't.

[Lodro Gyamtso]

About the price of Trimble TDC150, into my country it start at 3000 euro + taxes (24%) for accuracy of "sub meter". This is when we need accuracy only from satellites
There are 2 more accuracy levels (with RTK signals) and more money. The user has to install one access code into the device to upgrade the measurement accuracy.

[Lodro Gyamtso]

i will add some more info about what need a smartphone today, also the cost into my country, to manage to access high level of location accuracy, with the help of RTK (data)

device
as an example, i talk about model Spectra Precision SP20. This model is identical to Trimble TDC150.
Spectra Precision company is a division of Trimble company

Spectra Precision SP20 (2999 euro + 24% taxes)
without RTK subscription, this device has 50cm accuracy using only GNSS + SBAS satellites

RTK
except the cost of the subscription, the smartphone must have one sim card inside, with a valid number and internet data. This is a extra cost.
It will work Ok, when we are into the city, but what about when we are into the mountains ? Do we have internet ?


RTK subscription cost

RTK accuracy per month
- 30cm = 130 euro + 24% taxes
- 7/2 cm = 270 euro + 24% taxes
- 1cm =  440 euro + 24% taxes


RTK accuracy "no time limit" **** (for all the life of our device)
- 30cm = 1300 euro + 24% taxes
- 7/2 cm = 2680 euro + 24% taxes
- 1cm =  4400 euro + 24% taxes
**** this means, if we crash / broken our device, we must pay again the same price for this subscription, when we buy a new one device


software
- Spectra Geospatial Survey Mobile Software = 825 euro + 24% taxes
- Mobile Mapper Field Android = 440 euro + 24% taxes


personal thoughts
is there any possibility for the amateurs smartphone customers into the future to have better accuracy access, using so cheap android smartphones devices ?
---------------


this picture is from the trimble dtc150 manual, when we use the internal GNSS test software to determine the receiver accuracy

click on the image for bigger size

[Joop van der Velden]

Interesting details, thanks.

But I wonder what integration times are necessary for these accuracy's?

I mean - even with the cheapest smartphone I can get cm accuracy after months of averaging :)

[DK]

Nice research.

I still wonder if there are any smartphones out there that can take either SBAS or RTK corrections without looking huge an ugly.

The Lenovo Z6 Youth accuracy is really great. I hope that people can test their Z6's and show the results from around the world. I wonder if its only sub 1m accurate for the Beidou constellation.

[Dean Z]

DK, What is the the Lenovo Z6 Youth accuracy?

[Lodro Gyamtso]

Hi  Dean Z,

you can see my post No2 on Jun 8
I hope those measurements from Lenovo company to be real. We are all waiting to see someone else review (GNSS tests), from a youtuber or customer for this device

[Kurt Keller]

side by side comparison
left Xiaomi Mi 8 right vs. Lenovo Z6 lite (youth) on the left
What does the 0.0 E V. Acc mean? 
Lenovo is supposed to have dual frequency, but I don’t see any L5, E5a values.