GPS - How to test GPS signal quality, fix, record number of satellites in use and signal level of each ?

Author

How to test GPS signal quality, fix, record number of satellites in use and signal level of each ?

darius

2007-09-25, 10:33 pm

Hi,

I am looking for any working bluetooth scanner application
to test signal quality of my bluetooth gps units
and record data (number of satellites, signal level for each satellite
+ timestamp + geoposition)
to let me make decision which one gps bt unit is best for my intended
use.

One such application is Bluetooth Network Scanner but I get (126)
error code while trying to run it in discover mode (one module is
missing ).
Open source application, applet, API for PDA GPS running Win Mobile,
Windows 2003, Symbian gps -enabled gsm phone or Debian/Linux Nokia
770/800 is sought.
Logger function is of interest to let me scan and record signals
coming from some gps units at the same time.

Such application is already built in into most bluetooth- enabled
devices but no logging option or multi-scanning is offered.
Nokia 770/800 and other WiFi enabled PDAs, laptops run such
application to scan wireless networks.
But what I need is logging/recording function to record data coming
from some bt gps units at the same time.

Thanks for your kind advise.

Darius

Darius

2007-09-26, 12:33 pm

On Sep 26, 3:44 pm, DavidM < newsNO@_SPAMdjmorgan
.org.uk> wrote:
> darius wrote, On 25/09/2007 22:50:
>
>
>
> Not sure about comparing BT signal strength, I've not seen any software
> that can generate a quantitative strength value.
> As for comparing GPS signal strength, accuracy and data logging you
> could tryhttp://www.visualgps.net/VisualGPS/default.htm, it does all
> that and more.
>
> I doubt PDAs would be able to connect more that 1 or 2 devices at a
> time. PCs can connect multiple devices. If each BT device is attached to
> the computer separately and assigned a different com port number it
> should work OK. VisualGPS should run as multiple applications (although
> I've not tried that), each version running on the PC would need to be
> looking at a different com port.
>
> David
>
> --
> DavidM newsNO@_SPAMdjmorgan
.org.ukwww.djmorgan.org.uk

Thanks David,

I kept using VisualGPS to test my usb and rs DIN gps units.
As you have mentioned it I downloaded the latest free version 3.3.3
and there is a problem with virtual serial port.
BlueSoleil bluetooth driver for XP Windows installs bluetooth dongle
at port No. 7
Setting VisualGPS for the same port hangs it on.
Ok. Looking for virtual serial ports for my usb dongle I can't set a
port number above 8 in VisualGPS setting's window.
It hangs on on any port set.
Have you ever succeeded to connect bluetooth gps unit to VisualGPS ?

>From official webpage of VisualGPS:

GPS Receiver connected to a RS-232 port with NMEA 0183 output - NMEA
demo file included for those who do not have a GPS receiver

Ok. I am connecting my bluetooth gps unit to a virtual serial port not
directly to RS-232.
It shouldn't be a problem as I can connect my usb gps unit to work
with VisualGPS.

Still looking for how to set up to be working.
There is no chance to kill VisualGPS process, each time I have to
reset my PC.

Thanks.

Darius

Darius

2007-09-26, 3:33 pm

On Sep 26, 7:24 pm, DavidM < newsNO@_SPAMdjmorgan
.org.uk> wrote:
> Darius wrote, On 26/09/2007 18:02:
>
>
> I have got my Royaltek BT GPS to work with VirtualGPS, but remember now
> that I had the same problem as you. Windows put my BT GPS in com30. The
> work around that I used was to go into Windows device manager and find
> the GPS device, there should be a com port selector. I changed it to
> something that virtualGPS would like, probably 6. Windows bitches that
> changing com ports can cause errors, but I had no problems. VirtualGPS
> then worked OK. I've not had any system hangs with VirtualGPS in Windows
> XP. I don't use any extra drivers, only Windows standard BT tools.
>
> In case your BT GPS is sirf based, have you tried SiRFDemo?http://www.sirf.com/free_demo.htmlit lets you play with all the
> settings and look at the data streams.
> "SiRFDemo
> After installing on a Windows PC, SiRFDemo can be used to talk with
> SiRF-based GPS receivers and: see satellites being tracked, monitor
> their positions, and even measure signal strengths. If you're so
> inclined, you can even log data and change receiver settings."
>
> Don't enable static navigation like it did, it stopped all my software
> from seeing the device, easy to change back once I recalled my mistake.
> BT GPS devices always appear completely passive, but with this software
> you can get right inside them and really mess stuff up :)
>
> --
> DavidM newsNO@_SPAMdjmorgan
.org.ukwww.djmorgan.org.uk

Thanks David.
SirfDemo is really great application.
I am not sure if my bluetooth gps units are Sirf or not but they work.
I can select nmea mode and nothing hangs up.
I have selected serial port used by bt driver running on PC
(BlueSoleil) and it works great.

What I mean about scanning bluettooth devices like gps is Kismet
wireless scanner and other hotspot scan options in WiFi enabled
devices (laptop, PDA ..).
What I get is signal level and a name of a hotspot to select.
I would like to scan some bluetooth gps units to see which one works
better, gets fix faster and satellite signal is stronger.
The problem is successful pairing on both sides to be able to read
nmea messages.
Maby there is a software option to switch bluetooth gps unit into
brodcasting mode to give up manual pairing.
I have to know how to read mac address of gps unit in discovering mode
first.

Darius

Darren Griffin - PocketGPSWorld.Com

2007-09-28, 7:33 am

> Darius wrote, On 26/09/2007 19:52:[color=darkred
]
>
>

If all you are seeking to achieve is a performance comparison of the
GPS itself then why not use tools such as Winfast Navigator. This can
be used to repeat cold/warm starts etc.

--
Darren Griffin
PocketGPSWorld - www.PocketGPSWorld.com
The Premier GPS Resource for News, Reviews and Forums

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