GPS receivers: Difference between revisions
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I have a Garmin eMap and a Garmin GPS 25 LVC module, | I have a Garmin eMap and a Garmin GPS 25 LVC module, | ||
and Trimble Ace II and Trimble Lassen SQ modules. | and Trimble Ace II and Trimble Lassen SQ modules. | ||
I recently got a Magnavox | I recently got a [[Magnavox GPS reference station]]. | ||
==== Garmin ==== | ==== Garmin ==== | ||
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|- | |- | ||
| eMap || 15m/2m || 12 || $200 or so || Handheld, accepts RTCM for DGPS. Apparently a bad choice for Rinex software | | eMap || 15m/2m || 12 || $200 or so || Handheld, accepts RTCM for DGPS. Apparently a bad choice for Rinex software | ||
|- | |||
| GPS 10 || 15m/3m WAAS || 12 || $250 || bluetooth module | |||
|- | |- | ||
| GPS 15 || 15m || 12 || || bare module | | GPS 15 || 15m || 12 || || bare module | ||
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[http://www.embedtronics.com/GPS/lassenSQ.html DIY USB Lassen SQ] | [http://www.embedtronics.com/GPS/lassenSQ.html DIY USB Lassen SQ] | ||
[http://www.toppcompanies.com/tds/tds-component-models.htm ToppTec] purveyors of Trimble OEM modules | [http://www.toppcompanies.com/tds/tds-component-models.htm ToppTec] -- purveyors of Trimble OEM modules | ||
====Other links==== | |||
[http://www.delorme.com/ Delorme] -- consumer grade; Earthmates are WAAS enabled but the older Tripmates are cheap on eBay if you just need a NMEA GPS source. | |||
[http://www.leica.com/ Leica]<br> | |||
[http://www.thales.com/ Thales and Magellan]<br> | |||
[http://www.U-blox.com/ U-blox] sells mostly Sony modules.<br> | |||
=== GPS simulators === | === GPS simulators === |
Revision as of 16:57, 25 November 2005
Software
Visualization
GIS
The FreeGIS site http://www.freegis.org/ has the largest collection of freely available GIS/CGPS software. But the collection is not inclusive because policy prohibits them from listing free but protected commercial software.
GISuser has a collection of free tools.
So for example, Trimble's free mission planning program is not available there.
From email: Since 1997, I have implemented sets of Java, Web & Wireless GIS tools. Most of them are free to use. If you are interested, please visit http://www.jshape.com for more information. -- Shiuh-Lin Lee
ERmapper
MapWindow GIS
JUMP
Thuban
Quantum GIS QGIS
gvSIG is a tool oriented to manage geographic information. It is characterized by a user-friendly interface, with quick access to the most common raster and vector formats. In the same view it includes local as well as remote data through a WMS or WFS source.
Forestry GIS (fGIS™) is a compact but robust shapefile editing program, digitizer and GIS data query tool for Windows®
Mobile GIS Software
BBBike
ESRI ArcPad
GiMoDig
GPSDrive
Hoko
Mobile Geographics mapping and navigation for PDAs (This site is PalmOS oriented)
GPS
Transferring data into a GPS
Any platform
Garnix
Windows
Howto [1]
ArcMap extension for Garmin mxgeo (does not work on my computer) ($50 shareware)
Linux
gpsd data collector
http://www.ncc.up.pt/gpsman/wGPSMan.html
http://sourceforge.net/projects/gpstrans
Data formats and protocols
RINEX = Receiver Independent Exchange Format
Using RINEX to do differential postprocessing on your GIS data.
- Collect raw data using Garmin equipment
- Conversion of Raw Observation Data and Navigation Message Data to RINEX See TEQC software and GRINGO software
- Download CORS data
- Postprocess; using P4 (companion to Gringo)
JEEPS is a library that you are supposed to be able to use to build Garmin and post-processing applications. I don't think this means DGPS post-processing though...
Prairie has an intersting collection of information on using Garmin and Rhino products for DGPS. Rhino is a product of US Positioning.
"Proven Success With Rhino" (and therefore probably with RINEX conversion software?)
eTrex, eTrex Summit, eTrex Vista, eTrex Legend, GPS 12, GPS II +, GPS III, GPS III +, GPS V, GPS 16, GPS 16A, GPS 17N, GPS MAP 76, GPS MAP 76S, GPS MAP 176, GPS MAP 176C
NMEA
NMEA = National Maritime Electronics Association
NMEA 0183 standard is the ASCII format for (among many other things) GPS spatial data. You have to pay $250 to get a copy of the 0183 standard, these people don't know about the Internet and open standards yet. (The NMEA 2000 standard is $3800, ha ha ha.) If you are designing a new device and you have the bucks, you have to pony up. If all you want to do is grab data from your handheld and process it, the manufacturer manuals from both Garmin and Trimble are good. (Probably others too, these are just the ones I have read.)
RTCM
RTCM = Radio and Telephony Communications Maritime or something like that.
RTCM is another standards body in the business of selling information that really probably should be distributed for free. The publication set on differential GPS is $100. NTRIP which is the standard for distribution of the data over IP networks (via HTTP) is $50.
Trimble TSIP, proprietary binary format
Selected GPS Hardware
My interest is in learning how to do as much as possible for the least cost. I have a Garmin eMap and a Garmin GPS 25 LVC module, and Trimble Ace II and Trimble Lassen SQ modules. I recently got a Magnavox GPS reference station.
Garmin
Model | Accuracy | Channels | Price | Comments |
---|---|---|---|---|
eMap | 15m/2m | 12 | $200 or so | Handheld, accepts RTCM for DGPS. Apparently a bad choice for Rinex software |
GPS 10 | 15m/3m WAAS | 12 | $250 | bluetooth module |
GPS 15 | 15m | 12 | bare module | |
GPS 16 LVS, 16 HVS, 16A 3.3-6V / 6-40V / 8-40 V |
15m / <3m WAAS / 3-5 USCG RTCM | 12 channel | 2 serial ports, deck mount | |
GPS 17 | $200 | basically the same as a GPS 16 but in a white, pole mount case | ||
GPS 18 | 15m / 3m WAAS | 12 | $130 | CMOS serial or RS232 or USB hockey puck |
GPS 25-LVC (3.6-6V), -LVS(3.6-6V RS232), -HVS(6-40V RS232) | 15m / 5m DGPS | ? | bare module; capable of raw data output (pseudorange and phase) | |
GPS 35 / 36 | 15m / 5m DGPS | ? | 35 = mouse style, 36 = pole mount |
The GPS 17 is designed for marine applications but is often pressed into service in backpack style data collectors.
Trimble
GPS modules
Model | Accuracy | Channels | Connectors | Price (est) | Comments | |
---|---|---|---|---|---|---|
Pathfinder Pocket | 10m/2m DGPS | 8 | 2 RS232 via one DB9, SMB 3.3v, power | $500 | includes an external antenna. | |
M-Loc | 10m (no DGPS) | 12 | 3.3v 35mW(68mW)
25 x 25 x 6.9 mm |
$45 | FirstGPS software runs on host processor | |
Lassen SQ | 6-9m,no DGPS | 8 | 8 pin header, H-FL-R-SMT | 3.3v/100mW(133) 26x26x6 mm, 5.7g |
$45 | Use w/RF transition cable |
Lassen IQ | ??,no DGPS | 8 | 8 pin header, H-FL-R-SMT | ??3.3v/100mW(133) 26x26x6 mm, 5.7g |
?? | Updated more accurate version of SQ; need to look up and add specs |
Ace II | 25m/2m DGPS | 8 | 8 pin (2 CMOS TTL serial) SMB 5v/25mA | 5v / 95mA / .47W 82.6 x 46.5 x 11.5 mm |
cheap | Discontinued but I got one from eBay for $10 |
Ace III | 25m/2m DGPS | 8 | 8 pin (2 CMOS TTL serial) SMB 5v/25mA | 5v / 95mA / .47W 82.6 x 46.5 x 11.5 mm |
$80 | |
Lassen SK-8 | 25m/2m DGPS | 8 | 8 pin (2 CMOS TTL serial) SMB 5v/25mA | $ | Discontinued; use SKII | |
Lassen SKII | 25m/2m DGPS | 8 | 8 pin (2 CMOS TTL serial) SMB 5v/25mA | 5V / 95mA(120mA)/ .47W(.60W) | $80 | |
Lassen LP | 25m/2m DGPS | 8 | 2 serial and power via 8 pin header, MCX/3.3v 12mA | 3.3V / 55mA(67mA)/ .182W(.221W)
66.167 x 31.75 x 12 |
$55 | Low power; can be programmed to power up/down on schedule |
Style | Gain | Connector | Price |
---|---|---|---|
Micropatch | 26dB | 5m cable with MCX | $17 |
Hardmount micropatch | 26dB | TNC | $ |
Bullet | 35dB | 22m cable with SMB adapter | $ |
ToppTec -- purveyors of Trimble OEM modules
Other links
Delorme -- consumer grade; Earthmates are WAAS enabled but the older Tripmates are cheap on eBay if you just need a NMEA GPS source.
Leica
Thales and Magellan
U-blox sells mostly Sony modules.
GPS simulators
People make boxes that simulate NMEA-capable devices to allow testing when the actual data stream is not available and to enable regression testing.
NMEA data stream
The virtual serial port idea
Can I make a virtual serial port driver under Linux and fool VMware into using it??? Hmmm...
Yes. It's quite doable. You can hook a named pipe up as the serial port in the VMWare configuration settings and then write a program to read and write data on the pipe.
Another project, damn.
GPS mission planning software
A GPS mission consists of three phases. planning, execution, and post-processing. Mission planning software packages run on a desktop system at your office and assist with planning and post-processing phases.
The two commercial programs that I know of are tightly integrated with the field software so they are not all that useful unless you buy in to the whole enchilada -- data collector, proprietary data collector software, and "office" software.
The two programs are Trimble GPS Pathfinder Office for use with Trimble data collectors and TDS SoloOffice which works with TDS SoloField.
Planning for a GPS mission should include checking for suitable conditions. This includes knowing that the satellites will be positioned propitiously when you will be in the field.
I use Trimble's free planning program for this. You can download it from [insert Trimbles download site]. The bad part is that it is available only for Windows systems but it's handy enough that I use it anyway.