DroneDeploy / OneSky Analytics
GPS Forecast App
OneSky's GPS Forecast app lets DroneDeploy users quickly understand the health and availability of GPS prior to flying. The forecast is provided for 1 hour from the current time and predicts the maximum number of satellites that can be expected as well as the Horizontal Dilution of Precision (HDOP) of the navigation solution provided by those available satellites.
How Does It Work?
Once you have installed the OneSky GPS Forecast app from DroneDeploy's App Marketplace, you simply click the OneSky app from any flight plan to reveal the GPS forecast for that particular flight.
You will notice a series of charts showing a 1-hour forecast of GPS health & availability metrics.
What Does It All Mean?
Satellites Available: The graph showing number of satellites available will indicate how many satellites your receiver should be able to "see" in the sky from its current position.
HDOP: This value (Horizontal Dilution of Precision) is a common metric used to represent the overall horizontal positional certainty. In other words, with the given number of satellites available and their positions in the sky relative to the receiver, how "accurate" are the resulting Latitude and Longitude values from the GPS receiver. HDOP helps to quantify that accuracy. In general, values less than 1 are ideal, while values greater than 2 are not recommended for precision navigation.
Our analytics are based on continually updating and predicting the locations of each satellite in the various GNSS satellite constellations (GPS/GLONASS/GALILEO/Etc.). In order to determine which satellites your receiver will "see" involves accurately predicting the motion of all of the satellites in relation to the receiver's location on Earth. Other considerations are included such as minimum elevation angles from the receiver, number of receiver channels, and various noise factors.
Interested in using our analytics for your own applications? We offer this same analysis as an API for integrators and developers. Visit our Software as a Service site for more information or take a look at the API Documentation.