The BAAM.Tech PPK system uses a GPS base to provide corrections for the aircraft. You can use any base that has GPS L1/L2 and GLONASS G1/G2, BeiDou B1/B2, Galileo E1/E5b and SBAS constellations and can output a Rinex file with a 1 second observation. This will cover most CORS stations, and high-quality base stations. BAAM.Tech also sells an inexpensive base specifically for our PPK system.
· BAAM.Tech Base Station
· Base programmed Geodrive
· Laptop with Swift software
· MicroUSB connection
Test Process #
1. Setup base station outside.
2. Power on base station and verify power and USB light on Geodrive are on.
3. Connect laptop to Geodrive with USB cord connection.
4. Open Swift software.
5. Choose COM port from pop-up and verify connection in status window.
6. Watch graph and confirm satellites are detected.
a. If detected, test is complete.
7. Power off base station and remove Geodrive USB and check for trigger file.
Setting up the Base #
If Using a Base #
- Setup the base.
a. Measure the antenna height.
b. Our PPK software will use the height from the ground to the phase center of the antenna for its calculations.
- Turn on the base and set it up for a 1 second observation static Rinex file.
a. If using the BAAM.Tech base, make sure the USB thumb drive is inserted into the system before it is powered on. Once powered the base station will automatically start recording.
Post Processing #
- Save the aircraft PPK file and base file in separate folders. (We like to rename files to project name, rover, and base folders.)
- Save the collected images to a separate folder by themselves.
- Open the BAAM.Tech processing program.
- At the bottom there is a section to select what folder to save the project to click Browse and select a folder to save the project in.
- Click “Load Rover.”
- In the first box enter the antenna height of the PPK unit. (For the Phantom it is: 0.2038m) (make sure in meters & not feet)
b. Our PPK software will use the height from the ground to the phase center of the antenna for its calculations.a. If using another system enter the antenna height phase center of camera to phase center of antenna.
- Enter the SBP file from the aircraft. (you do not need the nav file below it as the program will automatically do it for you)
- Click load and confirm to convert to a Rinex file.
- Click “Load Base.”
- There are three options for entering the base location. If you read from the Rinex the location will not be as accurate but still useful for testing data in the field.
a. If you do not have your base location, you can use OPUS.
i. Enter the base file in Rinex format. (Use our converter if using our base)
ii. The antenna HXCGP500 NONE.
iii. Enter the antenna height from the phase center of the antenna to the ground.
- Enter your base location information in the following boxes.
- Enter the base antenna height this is the height from the phase center of the antenna to the ground.
- Select your base file. Click load base and confirm you want to convert to Rinex if using the BAAM.Tech base.
- Click Process. The software can take a while to do this step. The dial wheel will be spinning while its processing. The software is not frozen.
- Once that step is complete, go into the folder you saved the project to and open the event positions. You want to make sure the quality are all 1s (fix) or 2s (float). If they are 5, you either do not have the right base file, or you entered the location incorrectly. The majority should be 1s but some 2s are acceptable. Think of the 1s like ground control points if they are evenly spaced throughout the project then you are good, but if you have a full side of 2s you have the problem.
- Make sure the event numbers line up with images taken. If not, see where there are extra ground shots by looking at the altitude and copying and pasting the extra images in those locations.
- Once that all looks good close the event position file and click geotag.
- Enter the image folder location and the event position file. Be very careful, a wrong input will throw off the project.
- Click geotag and wait for the images to finish.
- Once finished, delete the extra images you copied.