Trimble Lassen
 |
 Trimble Lassen iQ Micro12 Channel 46240 20 GPS $15.00 Time Remaining: 1d 23h 13m Buy It Now for only: $15.00 |
 Trimble Lassen iQ SQ SMA Transition cable P N 58541 05 129mm HFL to SMA $3.50 Time Remaining: 22h 41m Buy It Now for only: $3.50 |
 Trimble Lassen iQ Micro12 Channel 46240 00 GPS $15.00 Time Remaining: 12d 6h 51m Buy It Now for only: $15.00 |
 Trimble Lassen iQ Micro12 Channel 46240 10 GPS $15.00 Time Remaining: 27d 10h 9m Buy It Now for only: $15.00 |
 Trimble Lassen iQ LP board module SQ GPS ANTENNA $21.98 Time Remaining: 19d 6h 57m Buy It Now for only: $21.98 |
 TRIMBLE LASSEN SK 8 GPS RECEIVER 12504 MHz 38115 20 BRAND NEW $37.04 Time Remaining: 2d 1h 3m Buy It Now for only: $37.04 |
 Trimble Navigation GPS SMB Antenna for BMW Lassen SK II $17.99 Time Remaining: 10d 5h 36m Buy It Now for only: $17.99 |
 GPS Antenna for Trimble Lassen iQ LP board module SQ $9.60 Time Remaining: 24d 15m Buy It Now for only: $9.60 |
 Trimble Lassen iQ Micro12 Channel 46240 05 GPS $15.00 Time Remaining: 12d 6h 54m Buy It Now for only: $15.00 |
 Trimble Lassen SQ Low Power Micro 8 Channel GPS module $15.99 Time Remaining: 15d 17h 45m Buy It Now for only: $15.99 |
 Trimble Lassen iQ LP board module SQ GPS ANTENNA $21.98 Time Remaining: 22d 13h 10m Buy It Now for only: $21.98 |
 Trimble Lassen iQ LP board module SQ GPS ANTENNA $21.98 Time Remaining: 14d 11h 1m Buy It Now for only: $21.98 |
 GPS Antenna for Trimble Lassen iQ LP board module SQ $13.20 Time Remaining: 2d 20h 22m Buy It Now for only: $13.20 |
 Trimble Lassen iQ LP board module SQ GPS ANTENNA $21.98 Time Remaining: 5d 13h 19m Buy It Now for only: $21.98 |
 Trimble Navigation GPS SMB Antenna for BMW Lassen SK II $17.99 Time Remaining: 19d 6h 59m Buy It Now for only: $17.99 |
 Trimble Navigation GPS SMB Antenna for BMW Lassen SK II $17.99 Time Remaining: 22d 13h 18m Buy It Now for only: $17.99 |
 Trimble Navigation GPS SMB Antenna for BMW Lassen SK II $17.99 Time Remaining: 5d 13h 19m Buy It Now for only: $17.99 |
 GPS Antenna for Trimble Lassen iQ LP board module SQ $9.99 Time Remaining: 18d 14h 3m Buy It Now for only: $9.99 |
 55db GPS Antenna for Trimble Lassen LP SQ Board Module $13.20 Time Remaining: 18d 12h 36m Buy It Now for only: $13.20 |
How to build a DGPS system with low cost GPS receivers?
DGPS
I have an idea for increase the accuracy of GPS measurements with low cost receivers.
-One unit will be connected to a computer and will be set in a fix known point that I will use to measure the difference of Latitude, Longitude and Altitude all the time and keep a log of the readings.
-The second unit will be moving in the field taking measurements of the points.
-When the readings from the field are concluded, the data will be put together with the Home unit and the correction to each reading will be the difference given by the reading of the home unit at that time.
How good or bad is the idea and where can I get more details. This is a project for precision agriculture in a third world country. I’m aware that there are systems of the shelve that do this. I’m trying an economic solution with recreational units or something like this unit, Trimble Lassen iQ Micro12 Channel 46240-20 GPS attached to an arduino board.
I don't wish to sound like a nay-sayer, but how accurate an offline fix does agriculture need?
Most commercially available units have WAAS/EGNOS decode feature which gives standard deviation fix accuracy to 2m real-time.
I think yours is a fine idea to give centimetre fix accuracy off-line.
I've used a similar method to correct for selective availability (back in the day).
Two computer systems, both logging NMEA messages from bog standard GPS receivers. One fixed at a defined location (placed on a triangulation point) the other roving unit used to log data points around a woodland. Logs were then compared offline, time-stamps aligned and SA difference computed.
I hope you manage to make this commercially viable.
Cheers.