Mobile phone GPS is what consumers generally consider any time looking at tracking cell phones. GPS (Global Positioning System) utilizing satellites is the most well-known and more accurate way of tracking. Still, GPS requires satellites to be in direct line of site of the mobile phone. It doesn’t work particularly well indoors or in dense metropolitan areas. If the cell phone is inside a structure, for example your house, restaurant, or often if driving the signals may not reach the mobile phone. From time to time heavy cloud cover and heavy foliage impedes with reception. Some cell phones may retain the last known GPS location, others might not.
A few worthwhile technical features and functions relevant to GPS phone tracking to think about include: Tracking Application “Persistence”. The tracking application 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 require the person using the phone to turn tracking on and off. Another thing relevant to Tracking Application “Persistence” and handset GPS location is the potential of over using 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 location 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 store location data internally so that it can be downloaded when convenient. Also known as “data logging,” which can keep location information even when the device has traveled outside the wireless network. Passive tracking is not a universal feature built-in to standard smartphone, but the newest cell phones tend to have Passive tracking features.
Much of the discussion dealing with cell tracking, cell phone GPS and mobile phone track 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 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 in medium earth orbit MEO. These satellites are also known as as the GPS Constellation, and they make an orbit once every 12 hours. They are not geostationary, but rather move at over 7,000 mph. They are solar powered but have battery backup 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 flying in the correct path. 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 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 move at about 7,000 mph to maintain 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 functioning to specification and the information they send to earth is accurate.
The GPS User Segment is composed 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 programs that make them work.
GPS receivers sometimes take a long time to become ready to use after being turned on because it must acquire some basic information in addition to capturing GPS satellite signals. This slow start can be caused when the GPS smartphone has been unused 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 location more quickly.
Another method of calculating cell phone location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation utilizes signal analysis data to calculate the time it takes signals traveling from the smartphone to a minimum of 3 cell towers to estimate position.
With Mobile Location Services (MLS), the GSM cell network provider uses triangulation algorithms to determine the location of the cell phone, its accuracy is proven to be much worse than that of GPS. MLS is further impacted by the same issues as GPS in the sense of the barriers impeding signal quality and the density of GSM towers to assist in the triangulation calculation. In rural areas position accuracy may be off as much as a mile.
Smartphone GPS Tracking Information
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