GPS on cell phones is what people commonly think about when considering locating cell phones. GPS (Global Positioning System) using satellites is the most recognized and more accurate way of tracking. But, GPS needs satellites to be in direct line of site from the mobile phone. It doesn’t work particularly well indoors or in dense cities. If the cellphone is in a structure, for instance your office, restaurant, or often if driving the signals may well not reach the mobile phone. At times heavy cloud cover and thick trees impedes with signals. Some smartphones will preserve the last identified GPS location, others may not.
Some worthwhile technical features and functions related to GPS cell tracking to consider include: Tracking Application “Persistence”. The tracking software on a smartphone typically must be enabled by the user. Depending on the mobile phone, the application may persist – remaining enabled when the phone is turned on after having been turned off. This feature can be especially important if phone tracking is important and you do not want to instruct the person using the phone to turn tracking on and off. Another issue related to Tracking Application “Persistence” and smartphone GPS location is the potential of over using 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 finding location along with how long the battery will last. One common way of minimizing battery and data use is Passive Tracking. Some cell phone GPS tracking devices will store location data internally so that it can be downloaded when convenient. Also known as “data logging,” it can maintain location 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 latest mobiles tend to offer Passive tracking features.
A lot of the discussion dealing with cell tracking, mobile GPS and cell phone track software could be helped by a GPS Satellite primer.
GPS satellites broadcast signals from space that GPS receivers utilize to determine 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 primary segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment made up of twenty-four to thirty-two satellites that orbit the earth at a height of about 12,000 miles. These satellites are referred to 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. They are solar powered but have battery reserve for when they are in the earth?s shadow. They are positioned 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 have a lifetime of about 10 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 equilibrium. This is the ideal location to place a stationary satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the earth-synchronous satellites need to travel at about 7,000 mph to sustain position. This is approximately the same speed as GPS satellites, but since communications satellites are 10,000 miles further away they don?t move relative to the earth.
The GPS Control Segment is composed of Master Control Station, an Alternate Master Control Station, and numerous dedicated and shared Ground Antennas and Monitor Stations that work together to ensure the satellites are working correctly and the information they send to earth is accurate.
The GPS User Segment consists 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 function.
GPS receivers determine location by precisely timing the signals sent 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).
Another method of formulating mobile phone location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation utilizes signal analysis data to determine the time it takes signals to travel from your telephone to no less than three cell towers to calculate location.
With Mobile Location Services (MLS), the GSM cellular network provider uses triangulation techniques to determine the position of the mobile phone, its accuracy is proven to be much worse than that of GPS. MLS is also impacted by the same issues as GPS in the sense of the interference affecting signal quality and the density of GSM towers to assist in the triangulation effort. In remote areas position accuracy may be off as much as a mile.
An Introduction To Mobile Phone GPS Tracking
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