What is static observation?
Static observation is a commonly used method in geographical surveying and navigation for accurately measuring the coordinates of points. In static observation, a receiver remains stationary at the observation point and collects satellite signal data over a period of time. These satellite signals contain navigation information transmitted by satellites, and by analyzing these signals, the coordinates of the receiver’s location can be calculated. Static observation typically requires a longer observation time to enhance measurement accuracy.
The advantage of static observation is its ability to achieve relatively high precision, but the trade-off is the longer observation time required and the need to ensure the stability of the receiver’s position during the observation period.
How to choose an observation site?
Sites for static should be chosen for their suitability for observations. A good site should have the following characteristics:
✓ No ob Document structions above the 15° cutoff angle.
✓ No reflecting surfaces (Lake, glass, etc.) that could cause multipath.
✓ Safe, away from traffic and passers-by. Possible to leave the receiver unattended.
✓ No powerful transmitters (radio, TV antennas, etc.) in the vicinity.
The computation of a baseline in data processing requires that the coordinates of one point (reference) are held fixed. The coordinates of the other point (rover) are computed relative to the “fixed” point.
How to Plan the Network?
A network consists of a set of baselines between network points. The design of the network will affect the results that are obtained from the survey. The following principles are recommended for good network design:
✓ Locate control of sufficient quality close to the project area
✓ Use good network geometry
✓ Build network redundancy
✓ Recommended networks
Recommended networks
➣ One receiver, the base receiver, is set up over a known point. The other receiver, the rover receiver, is set up over a point whose coordinates are unknown. They collect simultaneous observations at both the base and rover receivers for a certain period of time.
➣ Two receiver, the base receiver, is set up over a known point. The other receiver, the rover receiver, is set up over a point whose coordinates are unknown. When first unknown point is finish, not remove the base receiver and move the rover receiver to other unknown point.
➣ One receiver, the base receiver, is set up over a known point. It keeps continuous observation. The other receiver, the rover receiver, is set up over a point whose coordinates are unknown. They collect the observations in unknown point one by one around the base. In this way, it is more efficient, however the network geometry and reliability is poor and precision is not high.
Recommended observation time
The recommended synchronization observation time as below. For the PPK base station, the sample interval must set as 1s.
| Baseline Distance (km) | Approximate Time | Elevation Mask Angle (degree) | Sample Interval (s) |
|---|---|---|---|
| > 50 | ≥ 4 h | 15 | 10-30 |
| > 30 | ≥ 2-3h | 15 | 5-15 |
| > 15 | ≥ 1-2 h | 15 | 5-15 |
| > 5 | ≥ 30 min | 15 | 1-30 |
Static Field Step
✓ Set up the receiver and anchor legs so they will not move throughout the survey
✓ Measure and record slant height or bottom height
✓ Record station information, location, times and antenna height
| Station Marker | K001 |
|---|---|
| Antenna height (slant or bottom) | 1.372m |
| Receiver SN | T31U03356 |
| Start time to End time | 8:30-9:20 |
✓ Turn on the receiver, long press the static button to start the static. For different models of SinoGNSS receivers, please refer to user manual for the buttons and LED indicators
✓ Long press the static button or turn off the receiver when you have completed surveys
Above are the steps of how to do static observation. In the next blog, we will introduce the methods of SinoGNSS K8 receivers to manage static parameters.
cr: Static observation (1)_ComNav Technology Ltd