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GPS COMMUNICATION

Sunita Sarpotdar
Center-In Charge
Bai R.F.D. Panday Girls' High School

GPS and Spy Satellite technology is set to change communication and remote sensing. You can use it for defending your country for vehicle-tracking, adding the physically challenged or making driver-less cars.
Global Positioning Systems are used to communicate with Spy Satellites. A typical system consist of receiver, a transmitter and GUI on PDA (Personal data Assistant).
Generally satellite use this technology for communication. Spy satellites are hybrid of many satellite technologies. They are the series of technologies located at different latitudes and longitudial position around the globe that can capture live events and even have ability to read the letters on one rupee coins found on the street. These satellites are equipped with powerful digital cameras (of high focal length) as well as night vision cameras used to capture images and types of materials that may be moved at night in order to capture 3d image of an object, dat from only one satellite is insufficient. In such cases data from two or more satellites located near one another is superimposed on to selected object to produce 3D image.
A GPS is capable of sending and receiving signals from and to Spy satellite GPS accuracy is based on number of Spy satellites orbiting above specific location on the earth. The GPS finds its location by receiving processed information from 3 satellite located near each other.
Spy satellites use a simple technique to determine the positioning or extra location of an object. First they measure the distance from a point to object in focus and focal length with latitude and longitude position. The approximate location of an object currently in focus can be determined by producing similar information obtained on same subject from nearby Spy satellite. The location of the source object in focus can be computed.

HOW GPS WORK:
The satellite receiver, transmitter and PDA application forms a GPS unit. The GPS unit is linked to the Spy satellite. The communication from the GPS receiver/transmitter to the PDA is done either with infrared com port or standard com port is selected for communication it becomes wireless communication (between GPS receiver and transmitter along with PDA application)
When user makes query about location from PDA application PDA sends the query to com port which is connected to GPS transmitter hardware. In the GPS transmitter obtained query signal from PDA is modulated to the required frequency and send to nearby transmitter base station. Where it is processed and sends to Spy satellite.
PDA and GPS transmitter can also transmit signals directly to spy satellite. The Spy satellite then processes the request. When request is processed the result is sent back to the source GPS unit. The receiver can pick up the signal, demodulates it and sends data to the PDA. NMEA 0183C National Marine Electronic Association is one of the standards followed by GPS. The GPS unit normally produces positional information to NMEA standard. This is text based standard that has lines of data about location transmitted from GPS unit to PDA.

CONCEPT OF SPY SATELLITE
Series of satellite located on different longitudinal and latitudinal position around the globe to capture events.
They uses the very high focal length digital cameras and night vision cameras.

HOW TO CAPTURE 3D-OBJECT
Nearby satellites captures the images with digital cameras and superimposed to form images.

E.G. of GPS
NIME 0183C- National Marine Electronic Association. The GPS unit normally produces positional information to the NMEA standard. This is a text based standard that has lines of data about its location transmitted from GPS unit to PDA.