Throughout this discussion keep in mind that there is a fundamental difference between mobile phone GPS Tracking and Navigation. GPS cell tracking is typically related to someone maintaining records of either real-time or historical cell phone location, while Navigation deals with the handset user figuring out how to get from point A to point B. Just because a cell phone has GPS doesn?t mean that it can easily be used as a navigation device. Just like phone tracking, navigation requires third-party software.
A couple of important technical capabilities relevant to GPS cell tracking to consider include: Tracking Application “Persistence”. The tracking application on a handset typically must be enabled by the user. Depending on the handset, the application may persist – remaining enabled when the phone is turned on after having been turned off. This feature can be especially usefull if cell tracking is relevant and you do not want to require the person using the phone to turn tracking on and off. Another thing relevant to Tracking Application “Persistence” and handset GPS location is the possibility of wasting the battery. It is important to be able to remotely adjust how often of taking GPS position. Selecting real-time or periodic sampling affects both the accuracy of determining position as well as battery life. One typical way of controlling battery and data use is Passive Tracking. Some smartphone GPS tracking devices will record location data internally so that it can be downloaded when preferred. Also referr
ed to as “data logging,” it can keep position information even when the device has traveled outside the wireless network. Passive tracking is not a universal feature built-in to standard cell phone, but the newest mobile phones tend to offer Passive tracking capability.
A lot of the discussion dealing with cell tracking, mobile GPS and mobile phone track software could be helped by a GPS Satellite primer.
GPS satellites broadcast signals from space that GPS receivers use to provide three-dimensional location (latitude, longitude, and altitude) plus precise time. GPS stands for Global Positioning System and is a system that is made up of 3 main segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment is comprised of twenty-four to thirty-two satellites that orbit the earth at a height of about 12,000 miles. These satellites are also known as as the GPS Constellation, and they make an orbit once every 12 hours. They are not parked over one spot, but rather move 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 flying in the correct path. The satellites have a lifetime of about 10 years until all their fuel is exhausted.
GPS Satellites are not communications satellites. Geostationary or communications satellites are at a much higher orbit of about 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 force of gravity and centrifugal forces are canceled and are in equilibrium. This is the ideal location to park 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 maintain position. This is approximately the same speed as GPS satellites, but since they satellites are 10,000 miles further away they stay in place relative to the earth.
The GPS Control Segment consists of Master Control Station, an Alternate Master Control Station, and numerous dedicated and shared Ground Antennas and Monitor Stations that work together to make sure the satellites are functioning correctly and the information they send to earth is accurate.
The GPS User Segment consists of of GPS receivers taking the shape of mobiles 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, no matter whether within a smartphone, or simply a spucific Portable gps tracking device, estimate position by way of precisely timing the signals transmitted by GPS satellites. This critical information includes the time the message was transmitted, accurate orbital details (technically called the ephemeris), and also the basic system status and rough orbits of all GPS satellites (formally called the almanac).
If satellite signals are not obtainable, or accuracy and precision is less important than life of the battery, using Cell-ID is a useful alternative to GPS smartphone tracking. The location of the mobile phone can be approximated by the cell network cell id, that determines the cell tower the smartphone is using. By understanding the position of the tower, you’ll be able to know roughly the place that the cell phone will be. Nonetheless, a tower can cover a large area, from a few hundred meters, in higher populationdensity regions, to several kilometers in lower density areas. For this reason location CellID precision is lower than GPS accuracy. Having said that location via CellID still delivers a really viable alternative.
A Brief Introduction To Smartphone GPS Tracking
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