Throughout this discussion consider that there is a basic difference between cell phone GPS Tracking and Navigation. GPS cell tracking is typically related to someone keeping records of either real-time or historical mobile phone location, while Navigation deals with the smartphone user determining how to get from point A to point B. Just because a smartphone has GPS doesn?t mean that it can easily be used as a navigation device. Just like cell tracking , navigation requires third-party software.
A few important technical features and functions relevant to GPS cell phone tracking to consider include: Tracking Application “Persistence”. The tracking software on a handset usually 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 handy if mobile phone tracking is relevant and you do not want to require the person using the phone to turn tracking on and off. Another issue relevant to Tracking Application “Persistence” and smartphone GPS location is the possibility of battery drain. It is important to be able to remotely adjust how often of taking GPS position. Choosing real-time or periodic sampling affects both the resolution of finding location as well as battery life. One typical means of controlling battery and data use is Passive Tracking. Some smartphone GPS tracking devices will store location data internally so that it can be downloaded when preferred. Also referred to as “data logging,” which can maintain position data 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 cell phones tend to include Passive tracking capability.
Much of the discussion surrounding cell tracking, mobile GPS and mobile phone tracker 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 primary segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment consists of twenty-four to thirty-two satellites that orbit the earth in medium earth orbit MEO. These satellites are also known as as the GPS Constellation, and they are orbiting once every 12 hours. They are not geostationary, but rather move at over 7,000 mph. GPS satellites are solar powered but have battery reserve for when they are on the dark side of the earth. They are placed so that 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 runs out.
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 force of gravity and centrifugal forces are offset and are in equilibrium. This is the best location to park 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 move at about 7,000 mph to keep 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 comprised 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 functioning correctly and the data they send to earth is accurate.
The GPS User Segment includes of GPS receivers taking the shape of smartphones and , laptops, in-car navigation devices and hand-held tracking units along with the people that use them, and the software programs that make them work.
GPS receivers sometimes take longer to become ready to use after being turned on because it must acquire some basic information in addition to finding GPS satellite signals. This slow start is sometimes caused when the GPS device has been unused for days or weeks, or has been moved a significant distance while turned off for. The GPS must update its almanac and ephemeris data and store it in memory. The GPS almanac is a set of data that every GPS satellite transmits. When a GPS receiver has current almanac data in memory, it can acquire signals and find initial location more quickly.
If satellite signals are not available, or accuracy is less important than life of the battery, employing Cell-ID is a good alternative to GPS mobile phone location. The location of the handset might be computed by the cell network cell id, that identifies the cell tower the smartphone is using. By understanding the location of this tower, then you can know roughly the location where the handset will be. However, a tower can cover a large area, from a couple of hundred meters, in high populationdensity regions, to a few miles in lower density regions. This is why location CellID accuracy is lower than GPS accuracy. Having said that monitoring via CellID still provides quite a viable substitute.
Cell Phone GPS Tracking Introduction
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