Throughout this discussion keep in mind that there is a basic difference between handset GPS Tracking and Navigation. GPS mobile phone tracking is typically related to a third-party keeping records of either real-time or historical smartphone position, while Navigation deals with the handset 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 phone tracking, navigation requires third-party software.
A few important technical features and functions related to GPS cell phone tracking to think about include: Tracking Application “Persistence”. The tracking software on a cell phone typically must be enabled by the user. Depending on the smartphone, the application may persist – remaining enabled when the phone is turned on after having been turned off. This feature can be particularly handy if mobile phone tracking is relevant and you do not want to instruct the person using the phone to turn tracking on and off. Another issue relevant to Tracking Application “Persistence” and cell phone GPS tracking is the potential of wasting the battery. It is important to be able to remotely adjust the frequency of taking GPS position. Choosing real-time or periodic sampling affects both the accuracy of finding position as well as how long the battery will last. One typical means of controlling battery and data use is Passive Tracking. Some mobile phone GPS tracking devices will record location data internally so that it
can be downloaded when convenient. Also known as “data logging,” it can keep position 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 hottest mobiles tend to have Passive tracking ability.
A lot of the discussion surrounding cell tracking, cell phone GPS and mobile phone tracking 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 is an acronym for Global Positioning System and is a system that is composed of 3 primary segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment incorporates twenty-four to thirty-two satellites that orbit the earth in medium earth orbit MEO. These satellites are referred to as the GPS Constellation, and they are orbiting once every 12 hours. They are not geostationary, they travel at over 7,000 mph. They are solar powered but have battery backup 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 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 force of gravity and centrifugal forces are offset and are in balance. 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 sustain position. This is just about the same speed as GPS satellites, but since stationary satellites are 10,000 miles further away they don?t move relative to the earth.
The GPS Control Segment made up of Master Control Station, an Alternate Master Control Station, and a host of dedicated and shared Ground Antennas and Monitor Stations that work together to make sure the satellites are working to specification and the information they beam down to earth is accurate.
The GPS User Segment is comprised 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 function.
GPS receivers determine location by precisely timing the signals sent by GPS satellites. This information 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 formulating mobile phone position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation utilizes signal analysis data to compute the time it takes signals traveling from the cellphone to a minimum of three cell towers to calculate location.
With Mobile Location Services (MLS), the GSM cellular network provider utilizes triangulation algorithms to estimate the location of the mobile phone, its accuracy is proven to be less than than that of GPS. MLS is also impacted by factors similar to GPS in the sense of the barriers impeding signal strength 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.
Smartphone GPS Tracking Basics
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