Soon GPS will become almost as basic as the telephone, or more likely included with every smartphone. GPS can calculate locations accurate to a matter of just a few meters. In fact, incredibly with advanced forms of GPS it is possible to achieve measurements to less than a centimeter!

In a sense it’s like assigning every square meter on earth its very own address. GPS receivers have become very economical as they have been miniaturized to just a few integrated circuits. Nowadays days GPS is becoming integrated into cars, boats, planes, construction equipment, movie making gear, farm machinery, laptop computers and especially cell phones.

Tracking mobile phones is a popular topic with a lot of interest. A lot of the discussion surrounding cell tracking, cell phone GPS and mobile phone track software applications could be helped by a GPS Satellite primer and glossary.

GPS stands for Global Positioning System. GPS satellites broadcast signals from earth orbit that GPS receivers use to determine three-dimensional location (latitude, longitude, and altitude) plus precise time. The GPS system is made up of 3 main segments: Space Segment, Control Segment and User Segment.

The GPS Space Segment incorporates twenty-four to thirty-two satellites that orbit the earth in medium earth orbit MEO. These satellites are referred to as the GPS Constellation, and they are orbiting once every 12 hours. They are not geosynchronous, they travel at over 7,000 mph. GPS satellites are solar powered but have battery reserve for when they are in the earth’s shadow. They are placed so that at any given time there are at least 4 satellites ‘visible’ from any point on earth. Small rocket boosters on each satellite keep them properly positioned. The satellites last about ten years until all their fuel is exhausted.

GPS Satellites are not communications satellites. Geostationary or communications satellites use a higher altitude 22,300 miles above the equator. These satellites are used for weather forecasting, satellite TV, satellite radio and most other types of global communications. At exactly 22,000 miles above the equator, the earth’s gravitational force and centrifugal forces are offset and are in balance. This is the best location to position a communications satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the geo-synchronous satellites need to move at about 7,000 mph to keep position. This is just about the same speed as GPS satellites, but since geo-synchronous satellites are 10,000 miles further away they stay in place relative to the earth.

The GPS Control Segment is comprised of Master Control Station, an Alternate Master Control Station, and a host of dedicated and shared Ground Antennas and Monitor Stations that work together to make sure the satellites are working to specification and the data they send to earth is accurate.

The GPS User Segment is composed of of GPS receivers taking the shape of cell phones and , laptops, in-car navigation devices and hand-held tracking units along with the people that use them, and the software applications that make them work.

GPS receivers determine location by precisely timing the signals transmitted by GPS satellites. This data includes the time the message was transmitted, precise orbital information (the ephemeris), and the general system health and rough orbits of all GPS satellites (the almanac).

Consider that there is a basic difference between cell phone GPS Tracking and GPS Navigation. GPS cell tracking is typically associated with someone maintaining records of either real-time or historical mobile phone position, while Navigation deals with the smartphone user determining how to get from point A to point B. Neither use works without some sort of third-party software program.

An impressive software package that features remote control of smartphone~cell phone~mobile phone~handset~device settings, and combines Cell Phone Tracking~Mobile Phone Tracking~Phone GPS Tracking with SMS text message, Call Log, MMS multi-media message monitoring, and a web account for storage and review is PhoneBeagle.

Global Satellite System Glossary of basic terms.

GPS The Global Positioning System is made up of 24 GPS satellites, portable GPS receivers, and various ground-based support facilities.

GPS receiverThe either a standalone handheld device or electronic unit mounted on a vehicle dashboard or other movable item such as a shipping container, and now particularly common to be found inside phone handsets . Abbreviated “GPS” in common use.

Global Satellite System Frequently Asked Questions

Why does GPS receiver only work outside?
GPS satellites are positioned in their orbits to be sure that from any point on earth there are a minimum four satellites in site at all times. Although the satellites send signals by radio wave, they needs a clear of site to the receiver. Once the GPS satellite drops behind the horizon, or a building, or even heavy cloud cover, the radio signal may not reach the receiver.

What do the satellites do?
The GPS satellites are broadcasting the time. Both the satellite and the GPS receiver use atomic clocks for extreme accuracy. By measuring the difference between the time given by the satellite and the time in the GPS receiver, the GPS can calculate the distance from the satellite.

How does the GPS satellite know where it is?
The satellites keep position archived inside in calculated tables. But they can deviate off course over time. To correct this, the satellite communicates with fixed reference stations located around the world. Each time it connects with the ground stations, the satellite adjusts its internal position tables.

Does a GPS receiver transmit information back to the satellite?
No, they don’t do that. GPS equipped mobile phones will transmit data but not to the satellite.