NEWSLETTER [Stay Up-To-Date]

GPS Partner Location Tracker / Logger. Can be placed in car, motorbike, handbag, etc. more >


GPS Senior Phone Tracker, to monitor and track the Elderly or Disabled person.

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GPS Watch Phone Tracker for monitoring, supervising and tracking of the Elderly or Disabled person.

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GPS/GSM Tracker for monitoring and tracking your Child, Partner, Elderly or Disabled person.

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Kid Phone Tracker for monitoring & tracking your Child. Alerts you on your mobile phone.

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GPS Vehicle Tracker. Track and protect your vehicle, with alerts on your mobile phone.

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GPS Pet Tracker Monitor, track and protect your pets from getting lost or stolen.

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GSM House Alarm. Will alert you via SMS or MMS on your mobile of an intruder.

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GPS/GSM Tracker for monitoring and tracking your Child, Partner, Elderly or Disabled person.

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Driver Fatigue Alarm is a wireless device to keep the driver awake when driving.

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3G-Alarm Camera shows video alerts on your mobile phone; worldwide use.

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Vehicle Tracker with GPS location tracking, vibration and crash alarm on your mobile.

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Automatic Video Recorder with integrated CMOS Camera and PIR detector.

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This GSM-Alarm Camera shows photo and SMS / email alerts on your mobile phone.

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GPS Watch Phone Tracker for monitoring, supervising and tracking of the Elderly or Disabled person.

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WHAT IS GPS (Global Positioning System)?
Basics of GPS

The Global Positioning System (GPS) is a satellite-based locating and navigating system consisting of a network of 24 orbiting satellites that are eleven thousand nautical miles in space and in six different orbital paths. The satellites are constantly moving, making two complete orbits around the Earth in less than 24 hours; that's about 2.6 kilometers per second. Depending on the type of receiver and certain other conditions, it is possible to achieve real-time position accuracies within meters or even centimeters, with position calculations several times per second.

Each satellite weighs approximately 1 tone and is about 5 meters across with the solar panels extended. Transmitter power is only 50 watts, or less!

The GPS constellation of satellites was declared operational in late 1995 and consists of 24 satellites orbiting Earth to provide worldwide coverage, 24 hours a day, free of charge. GPS receivers are passive, so the system can serve an unlimited number of users.

Navigation using GPS
GPS receivers ascertain their position and height by measuring the signals from three or more satellites simultaneously and determining their position using the timing of these signals. GPS operates using trilateration, which is the process of determining the position of an unknown point by measuring the lengths of the sides of an imaginary triangle between the unknown point and two or more known points. In the GPS system, the two known points are provided by two GPS satellites. These satellites constantly transmit an identifying signal. The GPS receiver measures the distance to each GPS satellite by measuring the time each signal took to travel between the GPS satellite and the GPS receiver.

The formula for this is:  Distance = Velocity * Time

Velocity of the GPS signal is the speed of light, approximately 300,000 Km/s. GPS transmissions occur on two frequencies: 1575.42 and 1227.60 MHz.

GPS satellites send two signals: a carrier and a pseudo-random code. The signals are timed by an atomic clock in the satellite, and the GPS receiver generates a matching code timed by its own synchronized clock. The time it takes for the signals to reach the receiver indicates how far away the satellite is. This calculation is generally performed using the pseudo-random code signal, but for better precision, the carrier signal can be used instead. To make position calculations, GPS receivers use signals from four or more GPS satellites. The first three satellites are used to triangulate a position. The fourth is used to improve the position's accuracy by factoring in the time offset between the satellite system's clock and the GPS receiver's clock.

Receivers vary in the precision of their data and in their ability to overcome adverse signal conditions. Some can process their readings instantaneously, while others merely collect data for post-processing. A good quality GPS receiver delivers data that is robust, reliable and repeatable.

How accurate is GPS, really?
A typical GPS receiver provides 10-15 meter accuracy, depending on number of satellites available, and the geometry of those satellites. To get within a centimeter or two, they must use correctional information and computing, as well as using more sophisticated radio reception techniques. Similar correctional information is also available for a typical GPS receiver. Then the accuracy can be improved to one or two meters (in some cases under a meter) through a process known as Differential GPS (DGPS). DGPS employs a second receiver at a fixed location to compute corrections to the GPS satellite measurements. How are these corrections provided to your GPS receiver? There are a number of free and subscription services available to provide DGPS corrections.

HOW DOES GPS WORK?
GPS Enabled Mobile Phone / GPS Device

When you turn on your GPS unit or GPS enabled mobile phone for the first time, it starts to search for satellites; A GPS receiver's job is to locate four or more of these satellites, figure out the distance to each satellite, and use this information to determine its own location. Once the receiver makes this calculation, it can tell you the latitude, longitude and altitude of its current position. To make the navigation more user-friendly, most receivers will download this raw data into map.

A standard GPS receiver will not only place you on a map at any particular location, but will also trace your path across a map as you move. The receiver stays in constant communication with GPS satellites to see how your location is changing. With this information and its built-in clock, the receiver can give you valuable information.

Each of these solar powered satellites circles the globe making two complete rotations every day. The orbits are arranged so that at anytime, anywhere on Earth, there are at least four satellites "visible" in the sky. When the GPS Receiver needs to acquire the serial number, orbit and frequency of each satellite and store them, then the GPS chip in your receiver will use the signal received from the satellites to calculate your coordinates.

While determine your position, the GPS chip will store two types of data:

  • The serial number,orbitand frequency of each satellite
  • The coordinates of your last location

 Next time when you start your GPS tracker device, it does not need to search the satellites again, it can use the information stored previous, and need less time to acquire your current position. That is why when you go through a tunnel or pull out of a garage, you can get your current coordinates quickly.