Throughout this discussion consider that there is a basic difference between cell phone GPS Tracking and Navigation. GPS cell phone tracking is usually related to a third-party keeping records of either real-time or historical handset position, while Navigation deals with the cell phone user figuring out how to get from point A to point B. Just because a smartphone has GPS doesn?t mean that it can necessarily be used as a navigation device. Just like cell phone tracking, navigation requires third-party software.
Some important technical capabilities relevant to GPS mobile phone tracking to think about include: Tracking Application “Persistence”. The tracking software on a mobile phone typically must be enabled by the user. Depending on the cell phone, the application may persist – remaining enabled when the phone is turned on after having been turned off. This feature can be particularly usefull if cell tracking is important and you do not want to require the person using the phone to turn tracking on and off. Another thing related to Tracking Application “Persistence” and smartphone GPS location is the possibility of draining the battery. It is important to be able to remotely adjust how often of taking GPS position. Choosing real-time or periodic sampling affects both the accuracy of determining position along with how long the battery will last. One common means of minimizing battery and data use is Passive Tracking. Some handset GPS tracking devices will record location data internally so that it can be downloaded when preferred. Also referred to as “data logging,” it can maintain location data even when the device has traveled outside the wireless network. Passive tracking is not a universal feature built-in to standard mobile phone, but the latest cell phones tend to offer Passive tracking features.
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 utilize 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 composed 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 are orbiting twice a day. They are not parked over one spot, they travel at over 7,000 mph. GPS satellites are solar powered but have battery backup for when they are in the earth?s shadow. They are positioned 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 are parked in space 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 canceled and are in balance. This is the best location to park a communications satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the geostationary satellites need to travel 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 don?t move relative to the earth.
The GPS Control Segment includes Master Control Station, an Alternate Master Control Station, and a host of dedicated and shared Ground Antennas and Monitor Stations that work together to ensure the satellites are functioning correctly and the information they send to earth is accurate.
The GPS User Segment is comprised of of GPS receivers taking the shape of mobile 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).
Another way of determining cell phone position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation utilizes signal analysis data to compute the time it takes signals to travel from your smartphone to a minimum of three cell towers to calculate location.
With Mobile Location Services (MLS), the GSM cellular network provider utilizes triangulation techniques to try to pinpoint the location of the cell phone, its accuracy is proven to be much worse than that of GPS. MLS is further impacted by factors similar to GPS in the sense of the interference impeding signal strength and the density of GSM towers to help in the triangulation calculation. In rural areas position accuracy may be off as much as a mile.
Cell Phone GPS Tracking Tutorial
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