GPS technology in the Soil and Water Conservation

Global Positioning System (GPS) widely used in national defense, transportation, resource exploration, leisure and tourism, science experiments, water conservancy and other fields; GPS technology in the investigation of land resources, soil erosion, construction measurement, monitoring and evaluation of ecological environment and so on have been widely used. GPS successfully applied to soil and water conservation management to the high-tech development, implement the scientific concept of development is an important measure is to promote the only way for the construction of water information.

    1, GPS principles

    1.1GPS Overview

    Global Positioning System (NavigationSatelliteTimingandRanging / GlobalPositioningSystem) referred to as GPS, satellite navigation for the use of time and distance measurements to form a global satellite positioning system.

    The basic principle 1.2GPS

    Global Positioning System (GPS) navigation satellites is a radio navigation system, in space or on the ground, just use a GPS receiver to detect signals 3-4 satellites connected to the receiver, the receiver can calculate accurately location latitude and longitude, altitude, time, velocity and other parameters.

    1.2.1GPS principle components

    GPS system consists of GPS satellite constellation; ground monitoring system; GPS signal receiver of three parts.

    GPS Satellite Constellation: GPS constellation of satellites and the work of the work by the 21 satellites and three spare satellites, denoted by (21 +3) GPS constellation (the beginning of the 21st century will be the development of 24 +3 GPS satellite constellation.)

    Ground monitoring system: GPS navigation and positioning are known dynamic point; satellite position is based on the ephemeris satellite launch and orbital satellite motion described __ parameters calculable;