Mobile phone GPS is what people normally think of when considering locating mobile phones. GPS (Global Positioning System) using satellites is the most common and more accurate way of tracking. Yet, GPS needs satellites to be in direct line of site of the handset. It doesn’t work very well indoors or in dense urban centers. In the event that the phone is inside a structure, for instance your office, shopping center, or often if driving the signals may well not reach the smart phone. At times thick cloud cover and dense foliage impedes with signals. Some cell phones will store the last identified GPS location, others might not.
Several worthwhile technical capabilities relevant to GPS cell phone tracking to think about include: Tracking Application “Persistence”. The tracking application on a handset usually 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 especially usefull if cell 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 tracking is the possibility of draining the battery. It is important to be able to remotely adjust the frequency of taking GPS position. Selecting real-time or periodic sampling affects both the resolution of determining location along with battery life. One typical means of minimizing battery and data use is Passive Tracking. Some cell phone GPS tracking devices will store location data internally so that it can be downloaded when preferred. Also referred to as “data logging,” which 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 cell phone, but the hottest mobile phones tend to have Passive tracking ability.
A lot of the discussion dealing with GPS 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 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 consists 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 make an orbit once every 12 hours. They are not geostationary, they travel at over 7,000 mph. They 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 last about ten years until all their fuel runs out.
GPS Satellites are not communications satellites. Geostationary or communications satellites are at a much higher orbit of about 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 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 geo-synchronous satellites need to move at about 7,000 mph to maintain position. This is approximately the same speed as GPS satellites, but since geo-synchronous 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 is composed 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 programs that make them function.
GPS receivers determine position by precisely timing the signals sent 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).
If satellite signals are not available, or precision is less important than life of the battery, applying Cell-ID is a viable substitute to GPS smartphone tracking. The position of the mobile phone can be determined by the cell network cell id, that determines the cell tower the cellphone is connected to. By having the location of this tower, then you can know roughly the location where the handset might be. However, a tower can cover a large area, from a couple of hundred meters, in high populationdensity regions, to a few miles in lower density areas. This is the reason location CellID precision is lower than GPS accuracy. Nevertheless location using CellID still presents a really handy substitute.
Mobile Phone GPS Tracking Introduction
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