Throughout this discussion consider that there is a basic difference between handset GPS Tracking and Navigation. GPS phone tracking is usually related to a third-party keeping records of either real-time or historical smartphone position, while Navigation deals with the smartphone 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 mobile phone tracking, navigation requires third-party software.
Several important technical capabilities relevant to GPS cell phone tracking to consider include: Tracking Application “Persistence”. The tracking application on a device 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 important if cell 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 smartphone GPS location is the possibility of battery drain. 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 finding location as well as battery life. One typical means of controlling 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,” it can keep location data even when the device has traveled outside the wireless network. Passive tracking is not a universal feature built-in to standard handset, but the newest cell phones tend to have Passive tracking capability.
Much of the discussion dealing with GPS tracking, mobile GPS and cell 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 stands for Global Positioning System and is a network that is composed of 3 main 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, they travel 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 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 gravitational force and centrifugal forces are canceled and are in equilibrium. 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 geostationary satellites need to travel at about 7,000 mph to maintain position. This is approximately the same speed as GPS satellites, but since stationary 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 a host of dedicated and shared Ground Antennas and Monitor Stations that work together to ensure the satellites are functioning to specification and the data they send to earth is accurate.
The GPS User Segment includes 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 longer to become ready to navigate after being turned on because it must acquire some basic information in addition to finding GPS satellite signals. This delay is sometimes caused if the GPS mobile phone has been unused for days or weeks, or has been transported a far 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 capture satellite signals and determine initial position faster.
Another method of calculating device position is Triangulation or Mobile Location Services (MLS). Cell Tower Triangulation employs signal analysis data to calculate the time it takes signals to travel from your smartphone to no less than three cell towers to calculate position.
With Mobile Location Services (MLS), the GSM cellular network provider utilizes triangulation techniques to compute the location of the mobile 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 strength and the density of GSM towers to help in the triangulation calculation. In rural areas location accuracy may be off as much as a mile.
An Overview Of Mobile Phone GPS Tracking