GPS on cell phones is what people normally consider any time checking out tracking smartphones. GPS (Global Positioning System) utilizing satellites is the most recognized and more accurate means of tracking. Yet, GPS demands satellites to be in direct line of site of the smartphone. It doesn’t work as well indoors or in dense urban centers. If the handset is inside a building, for instance your office, restaurant, or often riding in a car the signals may not get to the smart phone. At times dense cloud cover and dense trees interferes with signals. Some smartphones will store the last identified GPS position, others may not.
A couple of important technical features and functions related to GPS mobile phone tracking to think about include: Tracking Application “Persistence”. The tracking software on a smartphone typically 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 particularly important if cell phone tracking is relevant 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 cell phone GPS tracking is the potential of wasting the battery. It is important to be able to remotely adjust how often of taking GPS position. Selecting real-time or periodic sampling affects both the accuracy of determining location along with how long the battery will last. One typical means of controlling battery and data use is Passive Tracking. Some smartphone GPS tracking devices will record location data internally so that it can be downloaded when convenient. Also referred to as “data logging,” it can keep position 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 most up-to-date mobiles tend to include Passive tracking capability.
A lot of the discussion dealing with GPS tracking, cell phone GPS and cell phone tracker software could be helped by a GPS Satellite primer.
GPS satellites broadcast signals from space that GPS receivers use 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 is comprised of 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 twice a day. They are not geosynchronous, but rather move at over 7,000 mph. They are solar powered but have battery backup 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 canceled and are in equilibrium. This is the best location to position a communications satellite. The earth rotates at about 1,000 miles an hour, and because of their high earth orbit the geo-synchronous satellites need to move at about 7,000 mph to maintain position. This is just about the same speed as GPS satellites, but since earth-synchronous satellites are 10,000 miles further away they stay in place relative to the earth.
The GPS Control Segment incorporates 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 information they beam down to earth is accurate.
The GPS User Segment consists of of GPS receivers taking the shape of handsets 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, irrespective of whether in a smart phone, or a spucific Gps tracking device, calculate location through precisely timing the signals sent by GPS satellites. This data incorporates the time the message was transmitted, specific orbital data (technically referenced as the ephemeris), and also the basic system condition and calculated orbits of all GPS satellites (formally referenced as the almanac).
Another way of calculating device location 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 cellular phone to a minimum of 3 cell towers to determine location.
With Mobile Location Services (MLS), the GSM cellular 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 also impacted by the same issues as GPS in the sense of the barriers affecting signal quality and the density of GSM towers to assist in the triangulation effort. In rural areas location accuracy may be off as much as a mile.
Smartphone GPS Tracking Intro
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