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GPS Solution - GPS can measure the moving direction of a rigid object

Январь 12th, 2016 by homesecuirtycameras and tagged , , ,

Currently, GPS ( tracking platform ) is the best known and most used satellite positioning system. Over the past 30 to 40 years, several other positioning solutions have been deployed for use in various scenarios, based on various approaches, using infrared, ultrasound, image processing or electromagnetic waves. Positioning or location can be understood as the unambiguous placement of a certain individual or object with respect to a known reference point. This reference point is often assumed to be the center of the Earth coordinate system. In practice, Mobile Positioning and Tracking João Figueiras and Simone Frattasi the reference point can be any point on the Earth that is known to the system and which all the coordinates can relate to. Although the position itself is obviously a very important source of information, this position must be related to a specific time to be even more useful.

In particular, when we consider tracking systems, time information is a key necessity, not only for knowing the position of a certain device at a specific time, but also for inferring higher-order derivatives of the position, i.e., speed and acceleration. Thus, “tracking” is a method for estimating, as a function of time, the current position of a specific target. “Navigation” is a tracking solution that aims primarily at using position information in order to help users to move towards a desired destination. The sever has associated a relational database to store all information about users, devices, and sessions, and a spatial database to support the storage of spatial information, such as the GPS magnetic tracker fixes from all the mobile devices. The location-based application here also responds to queries sent from the “control station,” or main monitoring station, to obtain the GPS fixes of a particular user or group of users and display their positions in a graphical user interface in real time.

GPS also employs TOA ranging and threedimensional positioning model to calculate user position. The measurement of vehicle GPS tracking device positioning model is similar to two dimensional positioning model. Assume that each satellite transmits a unique ranging signal in space. A satellite has a clocks synchronized with others clocks built on other satellites. The clock synchronization and orbit plane of these satellites are monitored and controlled by the control segment (MCS).

GPS also can measure the moving orientation (direction) of a rigid object, e.g., a vessel, an aircraft, etc. A GPS receiver also has a clock synchronized to GPS system time. Ranging signals transmitted from GPS satellites contain time information. It enables the receiver to measure the propagation time of the ranging signal left the satellite based on satellite clock time. We can find that the user position would be at two possible points, and only one of the points is the correct user position. For the user position, it is generally locates on the surface of the earth. Therefore, the lower one of two points will be the true position. In order to measure the more accurate user position, the fourth satellite will be applied to calculate and fix the user’s altitude. In addition GPS can determine the user velocity. The most popular used method is based on estimating the Doppler frequency of the received GPS signals.

More GPS Tracking Solution at http://www.jimilab.com/ .

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Using GPS Tracking Device will enhance your basic navigational skills

Декабрь 29th, 2015 by homesecuirtycameras and tagged , , ,

Most GPS receiver cases have a loop on the back to hold the case on a belt. If you’re wearing shorts or tights and don’t have a belt, waist packs for carrying a radio or a cassette/CD player are an option. These packs can accommodate larger GPS receivers. They’re not very noticeable when you’re working out because they’re designed not to bounce much. Small fanny packs and waist packs that carry water bottles also carry a GPS receiver. If the GPS receiver is small, try carrying it in your front pants pocket. I’ve carried a GPS while running and cross-country skiing in trail-running shorts and tights with zipper pockets. Although satellite reception is sometimes lost while under heavy tree cover, the GPS receiver records track data as long as I have a mostly clear view of the sky.

Using GPS will greatly enhance your understanding of the map-and-compass technique, but it’s wise to hone basic navigational skills before or in conjunction with use of a GPS tracking device. When out in the field, you will develop your own style of GPS use. You may want to plot a course ahead of time, upload it to your GPS, and follow that. You may want to upload only key points of your journey such as crucial trail intersections, waterfalls, high points, or shelter locations. You may want to carry the GPS along without uploaded data and navigate without the aid of pre-plotted track points or waypoints. Or you may just want to have the GPS to turn on once or twice a day to check your position against a map.

The Timex Speed + Distance system is a cigarette pack-size GPS magnetic tracker that straps on your arm and transmits data to a special wristwatch. You can look at your watch and see how far you’ve gone and how fast you’re going. Timex updated the system in 2003, adding more components and calling it Bodylink. In addition to the GPS receiver and watch, the Bodylink includes a heart-rate monitor (the GPS receiver, watch, and heart-rate monitor ) and a data recorder that collects data from both the GPS receiver and the heart-rate monitor. You can connect the data recorder to your personal computer to upload your workout data and analyze it with the included software.

Even with vehicle GPS tracking device technology becoming better every day, it is still a good idea to have backup navigation. Having a paper map, a simple compass,and knowledge of manual navigation is a good, safe practice of prudent navigators! Remember, GPS is a complement to navigation and should not be the only navigational tool you use.

The main disadvantage to carrying your GPS receiver on or below your waist is that it’s not the best place for satellite reception. There’s a good chance that you’ll lose the signal in areas with reduced satellite coverage. If you use a hydration pack or a lightweight backpack, you can get your GPS higher for better satellite reception by mounting the case either on one of the front shoulder straps or putting the GPS receiver in the upper, top pocket of your backpack. (It isn’t as accessible in the backpack pocket but should get good satellite reception.

More GPS Tracking Solution at http://www.jimilab.com/ .

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