GPS on cell phones is what people generally consider when investigating tracking cell phones. GPS (Global Positioning System) using satellites is the most known and more precise means of tracking. But, GPS must have satellites to be in direct line of site of the handset. It doesn’t work really well indoors or in dense metropolitan areas. In the event that the mobile phone is in a structure, for example your school, shopping center, or often sitting in an automobile the signals may not reach the smart phone. Often thick cloud cover and dense trees impedes with signals. Some mobile phones may hold on to the last known GPS position, others may not.
Some important technical capabilities relevant to GPS cell phone tracking to consider include: Tracking Application “Persistence”. The tracking application on a cell phone 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 especially important if cell phone tracking is worthwhile 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 smartphone GPS location is the potential of battery drain. 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 battery life. One common method 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 convenient. Also known as “data logging,” which can maintain position information 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 most up-to-date mobile phones tend to have Passive tracking capability.
A lot of the discussion surrounding cell 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 utilize to provide three-dimensional location (latitude, longitude, and altitude) plus precise time. GPS stands for Global Positioning System and is a system that is composed of 3 main segments: Space Segment, Control Segment and User Segment.
The GPS Space Segment is composed 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 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 positioned 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 last about ten years until all their fuel is exhausted.
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 equilibrium. This is the ideal 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 travel at about 7,000 mph to maintain position. This is just about the same speed as GPS satellites, but since they 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 a host of 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 programs that make them function.
GPS receivers, no matter whether in a handset, or simply a spucific Gps tracking device, estimate position by accurately timing the signals passed on by GPS satellites. This information incorporates the moment the message was sent, specific orbital information (formally referred to as the ephemeris), along with the general system condition and approximated orbits of all GPS satellites (technically referred to as the almanac).
Another way of calculating device location is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation uses signal analysis data to compute the time it takes signals to travel from your smartphone to no less than 3 cell towers to calculate position.
With Mobile Location Services (MLS), the GSM cellular network provider uses triangulation techniques to try to pinpoint the position of the cell phone, its accuracy is proven to be less than than that of GPS. MLS is further affected by the same issues as GPS in the sense of the interference impeding signal strength and the density of GSM towers to help in the triangulation effort. In remote areas location accuracy may be off as much as a mile.
Cell Phone GPS Tracking Basics
No comments:
Post a Comment