DGPS Survey – Veerabhadra Digital Land Survey

DGPS (Differential Global Positioning System) survey is a surveying technique that utilizes a combination of GPS (Global Positioning System) receivers and a reference station to provide more accurate positioning data. The reference station is a stationary GPS receiver with known coordinates, and it broadcasts correction signals to the mobile GPS receivers in the field.

Here’s a general overview of how a DGPS survey works:

Setup: The reference station is established at a known location with precise coordinates. It collects data from the GPS satellites and calculates the difference between the measured positions and the known positions.
Data collection: The mobile GPS receiver, typically mounted on a surveying pole or a surveying instrument, is taken to various locations where data needs to be collected. The GPS receiver in the field simultaneously receives signals from the GPS satellites and correction signals from the reference station.
Differential correction: The mobile GPS receiver compares the correction signals received from the reference station with the GPS signals it receives from the satellites. It applies the correction factors to improve the accuracy of the GPS measurements.
Data processing: After completing the data collection, the collected GPS data is post-processed using specialized software. This software uses the known coordinates of the reference station and the correction information to calculate accurate positions for the surveyed points.

DGPS surveys are commonly used in applications that require high-precision positioning, such as land surveying, construction, mapping, and geodetic control. By using DGPS, surveyors can achieve centimeter-level accuracy in their measurements, which is significantly better than the accuracy obtained with standalone GPS receivers.

It’s worth noting that DGPS relies on the availability of a reference station and the transmission of correction signals. The coverage area of DGPS can vary depending on the location and the setup of the reference station network.