rtkviewer fails (update released)

PC=win10, lots of 64bit power, 16 GB ram , 8 T HD, 4k display…
with Norton security.
I just received 2 alphas for evaluation and use; Std and lite set.

  1. rtviewer craches in win 10 after connecting. I tested full screen->crash.
    I can not get or buy the license. I enabled rtviewer in Norton and run it as Admin.

(Also I tested with old win7 having some problems with windows updates and NET.
it gave notice of missing net framework involving internet features.)

  1. I tested standard and lite kit antenna. Both had low accuracy 15-3,5m max 8 satellites. I tested $100 Garmin Glo at the same spot and it gave 1,5m + more satellites, like 11. Glonass is here better than GPS. I do not know if Glonas is used by Alpha now. Garmin uses more satellites even with less signal and Alpha drops level under 30 satellites away. Is there a limitations without license for accuracy and satellites? Or is the receiver just bad?
  • If I buy the licence , do I get this to work? If the software worked?
    I noticed that when antenna was close the Alpha and USB power pack, the accuracy was bad. I thought it could be EMI on GPS frequency. Alpha+powerpack is in plastic box and my intention was to fix the antenna to this box too.
  1. I tested the Android Lefebure NTRIP client also. I could not configure and test yet the local NTRIP correction server fully. Because the Gps position is not accurate. Also the program did not save the setups like NTRIP ‘stream’ and I have to enter setups every time I enter the program. With Huawei M2-801L 8" notepad. I understand it is not your program, but I have no another somehow operational client.

I tested another Android client, RTKGPS+, too, but I could not use it because it could not read/input Alpha data stream as a Rover, propably because NMEA protocol could not be selected amount the selection. After 8 h I gave up this complicated software with limited information.

  1. For now I can use this Garmin Glo and it is smaller and more accurate.

  2. Is there any way to get even 25 cm accuracy with one Alpha + Lefebure NTRIP client and use local NTRIP server, which is very accurate, it is close, gives corrections and base location and is maintained by goverment here.

  3. If this works someday I think I could use 2 Alphas: base + rover with 4G connection on the site and use reference point with base station. But better would be use local public NTRIP with fixed IP server and professional equipment. Now it seems that next week I have to call and order a man with a Trimble to locate the gps coordinates.

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A1: On the RTK Viewer crash issue, might it be possible to try using this version that output additional debug message enabling us to understand the issue : www.polaris-gnss.com/RtkViewer-20181018( ? Please help capture screen image for us.

A2: Alpha by itself is a normal 2.5m CEP accuracy GNSS receiver. Upon first use it has no default data and may have less number satellites initially. After leaving it running for 12.5 minutes collecting full GPS almanac data, it’ll have all in view satellites. There is backup battery inside, so later use it’ll have more satellites than numbers seen on first use.

RTK works with carrier phase measurement, requiring much higher signal level than normal GPS receivers. Garmin GLO is a normal GPS/GLONASS receiver that can work with code phase measurement at lower signal level for meter-level accuracy.

Just for reference, Trimble Leica Novatel RTK receivers all have very poor sensitivity performance when compared to normal meter-level GPS receivers. The operating principle and requirements are different between RTK receiver and meter-level accuracy receiver.

The antenna should be kept at some distance from Alpha to avoid picking up digital noise from Alpha affecting signal reception performance. The distance seen with the photo images in the user guide or blogs provides some idea. With the smaller size UPM-Lite Kit antenna, the circular metal plate placed under the antenna will also give much better signal reception and RTK performance. If you have interest to try, mount the smaller antenna on the provided circular disc and place on your box that has Alpha and power bank inside, it should should have strong signal than without the metal disc. A solid larger size metalic plate covering surface the antenna is placed would also improve signal reception. If you wish to place antenna that close, some experimentation might be needed.

A3: The Lefebure NTRIP client does remember the settings entered. After inital setup once, later use only need to click connect, without needing to re-enter those NTRIP Caster connecting parameters. Not sure if there is something particular about your phone causing needing to re-enter paramater every time.

A5: The shipped Alpha receivers all are in default rover mode. But still need to have RTK Viewer running, getting serial number and have activation key in place to enable RTK function; otherwise it’ll only function as normal 2.5m CEP GNSS receiver.

Thank you for a quick answer.

After connect prgram writes nmea data on a windows then closes it after 2 s, then shows message 2 lines for 2 s then program closes. It does not wtite any debug.
I took a system internal process monitor ( google microsoft procmon.exe ) dump. You can see excatly what .net program does.

download from googledrive (318k) LogfileRTK2.CSV

LogfileRTK2.PML is a procmon file to easyli see the steps

I will remove these after some days. I could email these info or download only to support.

Please keep the files till next Tuesday. Will have our engineering look into it next Monday.

Thank you.

Here is windows error log. of the unhandled exception and program close. Helps programmer. ( as pdf) sorry it is in finnish but data is clear.

kohteessa System.Number.ParseSingle(System.String, System.Globalization.NumberStyles, System.Globalization.NumberFormatInfo)
kohteessa System.Convert.ToSingle(System.String)
kohteessa StqMessageParser.NmeaParser.ParsingNmeaGsa(System.String, NmeaType)
kohteessa StqMessageParser.NmeaParser.Process(Byte[], Int32, NmeaType ByRef, System.String ByRef)
kohteessa StqMessageParser.MessageParser.PrasingMessage(Byte[], Int32)
kohteessa StqMessageParser.MessageParser.Parsing(Byte[])
kohteessa RtkViewer.DeviceInformation+ParserClass.RunParser()
kohteessa System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)…

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I believe jjk is referring to https://www.maanmittauslaitos.fi/en/maps-and-spatial-data/positioning-services/dgnss-service (correct me if I’m wrong).

I would also like to know if it is possible to connect with Alpha as a rover to the DGNSS network or to one of its Geo++® GNSMART (http://www.geopp.de/gnsmart/) based mountpoints listed in ?

These DGNSS service do not support below RTCM 3.2 messages for RTK operation:

1074/1075/1076/1077 for GPS MSM4/MSM5/MSM6/MSM7 Observations
1084/1085/1086/1087 for GLONASS MSM4/MSM5/MSM6/MSM7 Observations

Thus will not work with Alpha RTK Receiver.

BTW, single-frequency DGNSS at most gets sub-meter accuracy, 25cm accuracy is not possible. Dual-frequency DGNSS could get 30 ~ 40 centimeter level accuracy.

Here is a short sample data from USB=COM3-Alpha port as text.
I will remove it after a week…
( perhaps it has something to do that number 1,00 ( local finnish) and 1.00 (english) is parsed differently and causes exception)
I though I tested with US english ( desimal separator dot) but windows wanted to install OS in finnish even though I hate it and selected as US english). I try later this again.
Decimal is data is dot and separator is comma. As it should be.
-Anyway it is good practice to handle all exceptions in .NET or the program crashes if there are any anormalities (try{} catch{…} )

-I did not yet 'parse ’ your replay starting from RTCM 3.2 … Anyway I can not change satellites not network nor windows

RTCM 3.2 or 3.3 is used and can be selected. 3.2 messages are

Message type Interval Content
1006 10 s Reference station information
1071 1 s GPS code observations and differential correction
1081 1 s Glonass code observations and differential correction

Use of DGNSS service

The differential corrections are sent over the internet according to Ntrip protocol (Networked Transport of RTCM via Internet Protocol).
And this seems to work in Android Lefebure NTRIP client ( I guess. ) Without RTK. Anyway I receive data.
(I think I can use that data with RTKGPS+ , too. Only it cannot input Alpha data (in NMEA format?) and I cannot define Antenna type in software. (public domain library) It can only input trimble, ubox … etc protocols.

Although the message is formatted according to NTRIP protocol, Message 1071 and 1081 are not supported by most RTK receivers, among them it includes ublox NEO-M8P, also the SkyTraq S1216F8-RTK module that Alpha uses.

I could now run rtkviewer when I changed in wondows that desimal separator is dot. There is the problem. Net uses \cultural\ parsing. The numbers are parsed wrong then. This affects all programs and I have to change it back after rtkviewer.

The 1071 and 1081 are coming from internet, from DGNSS service or base station. Not from satellites? It is Lefebure clients problem? I quess.

Is there a way to test this Alpha RTK mode without buying $190 lisence ?
To see that I can get more precise location with this system. I have no idea if the base works in kinematic mode now or just differential.
I could use use 1 now and finally 2 if it works.
best deal for R&D now and future deals later. without public box.

Thank you for the information on decimator separator issue. Our engineering is looking into the problem.

1071 and 1081 comes from DGNSS base station. These messages are not recognized by many RTK receivers, including Alpha.

Alpha can work with Trimble/Leica base station with Virtual Reference Station (VRS) service. A pair of Alpha in base/rover GPS/GLONASS RTK mode can work up to 7Km baseline distance for non-Asian customers, and 10Km baseline distance in GPS/Beidou RTK mode for Asian customers.

Besides $190/Unlimited usage plan, there is also the $40/Month option available.

Latest version RTK Viewer should have fixed the reported crash issue, connect issue, and exit issues.

download instructions version RTK Viewer

Run your existing RTK Viewer, it’ll update automatically when detecting new version available; the PC the RTK Viewer is executed will need to be Internet connected.