Throughout this discussion consider that there is a basic difference between handset GPS Tracking and Navigation. GPS cell phone tracking is usually associated with a third-party maintaining 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 cell phone 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.
A few important technical features and functions relevant to GPS cell tracking to think about include: Tracking Application “Persistence”. The tracking application on a smartphone typically must be enabled by the user. Depending on the device, the application may persist – remaining enabled when the phone is turned on after having been turned off. This feature can be especially usefull if mobile phone tracking is important and you do not want to require the person using the phone to turn tracking on and off. Another issue related to Tracking Application “Persistence” and mobile phone GPS location is the potential of draining 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 resolution of finding position along with how long the battery will last. One typical way of minimizing battery and data use is Passive Tracking. Some mobile phone GPS tracking devices will store location data internally so that it can be downloaded when preferred. 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 mobile phone, but the hottest mobile phones tend to offer Passive tracking features.
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 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 includes 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 geosynchronous, they travel 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 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 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 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 travel at about 7,000 mph to sustain 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 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 to specification and the data they send to earth is accurate.
The GPS User Segment made up 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 sometimes take a long time to become ready to navigate after being turned on because it must acquire some basic information in addition to capturing GPS satellite signals. This slow start is sometimes caused when the GPS mobile phone has been turned off for days or weeks, or has been transported 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 satellite signals and calculate initial position faster.
Another way of formulating mobile phone position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation uses signal analysis data to determine the time it takes signals to travel from the smartphone to at least 3 cell towers to estimate position.
With Mobile Location Services (MLS), the GSM cellular network provider utilizes triangulation techniques to try to pinpoint the location of the mobile phone, its accuracy is proven to be less than than that of GPS. MLS is further impacted by factors similar to GPS in the sense of the barriers impeding signal quality and the density of GSM towers to help in the triangulation calculation. In remote areas location accuracy may be off as much as a mile.
Mobile Phone GPS Tracking Information
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