1 of 11

Real-time or Post-Processed?

Depends on the accuracy you need for the project

2 of 11

If you want the best possible GNSS accuracy

2 WEEKS BEFORE, MARK (TENT POLE, REBAR, ETC.) AND COLLECT 2HRS+ BASE STATION DATA

DURING COLLECT 4HRS+ BASE STATION DATA, ROVER DATA 1MIN+

POST-PROCESS 2 WEEKS AFTER

3 of 11

RTK, PPK, PPP

RTK- Real-time Kinematic

Realtime corrections are sent to the rover or drone from the basestation connected to the internet

PPK- Post-processing Kinematic

You collect the data without any internet connection, then post-process it after the fact

PPP- Precise Point Positioning- You can get accuracy with a wait

FINAL: the accuracy is about 2 cm, available 13-15 days after the end of the week

RAPID: the accuracy is about 5 cm, available the next day

ULTRA RAPID: the accuracy is about 15 cm, available every 90 minutes

Stop and Go Kinematic- Drone stops for each picture for retrofitted RTK

This is mainly for when you want RTK but you do not have a hotshoe attachment on the camera.

4 of 11

GNSS Configuration Options

CORS, Base (4hr), and Rover (1min)

CORS and Rover (1 min)

CORS, Base (4hr) and RTK UAS

5 of 11

Retrofitted RTK

6 of 11

How do I connect to RTK?

  • In most cases need cellular to access internet
  • Have to have an account with Network Transport of RTCM (Radio Technical Communication for Maritime Services) over internet protocol (NTRIP) or Virtual Reference Station (VRS), can use Emlid Caster for free
  • Montana has a system- free for educational for now
  • Most are subscription based

7 of 11

8 of 11

What is a Baseline?

OR

Distance from CORS to Base

Hopefully less than 100km

Distance from Base to Rover

Ranges up to 8km

Put Base on top of a hill or building if possible

Works best in line of sight

9 of 11

Why Baseline Matters

10 of 11

More Baseline Stuff

11 of 11

Why Baseline Matters

  • Base to Rover
    • 8km max in good line of sight with base on a building
    • About 5km if base is on a hill and rover on a plain below with good line of sight
    • About 1km if line of sight is poor, in the forest, etc.