Description
GPS is a space-based satellite navigation system. It provides location, date and time. This navigation system made up of network with 24 satellite placed into orbit.
- GPS navigation device provides data in all weather conditions.
- GPS satellite placed in orbit from a distance of 20,000 km above the earth.
- A satellite makes complete two revolutions every day.
- Each GPS receiver gets the information from four satellites.
- GPS receiver is used to calculate the location from the information obtained from four satellites.
- Calculations based on the mathematical principle called trilateration.
Calculating Location
- EXAMPLE
To know the exact location.
There is four person
Person 1= unknown location, (GPS Receiver)
Person 2=Chennai, (Satellite 1)
Person 3=Bangalore (Satellite 2)
Person 4= Coimbatore (Satellite 3) - Person1 ask person2 where am I, he says you are 139km from Chennai.
- Person1 ask person3 where am I, he says you are 215 km from Bangalore.
- Person1 ask person4 where am I, he says you are 391 km from Coimbatore.
GPS Received Data In NMEA Format
- $GPBOD = Bearing, origin to destination.
- $GPBWC = Bearing and distance to waypoint, great circle.
- $GPGGA = Global Positioning System Fix Data.
- $GPGLL = Geographic position,latitude / longitude.
- $GPGSA = GPS DOP and active satellites.
- $GPGSV = GPS Satellites in view.
- $GPHDT = Heading, True.
- $GPR00 = List of waypoints in currently active route.
- $GPRMA = Recommended minimum specific Loran-C data.
- $GPRMB = Recommended minimum navigation info.
- $GPRMC = Recommended minimum specific GPS/Transit data.
- $GPRTE = Routes.
- $GPTRF = Transit Fix Data.
- $GPSTN = Multiple Data ID.
- $GPVBW = Dual Ground / Water Speed.
- $GPVTG = Track made good and ground speed.
- $GPWPL = Waypoint location.
- $GPXTE = Cross-track error,Measured.
- $GPZDA = Date and Time.
Hardware Required
- GPS Module.
- PIC16f877a MicroController.
GPS Pinout
- Vin= +5V.
- Tx= Rx of Microcontroller.
- Rx= Tx of Microcontroller.
- Gnd= Ground.
Circuit
Virtual Circuit
