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How to use this information for navigation?In the first (non-mapping) GPS receivers this information was made visible on a small LCD screen. A small computer program in the receiver translated the information about subsequent positions into dots on the screen. This way you can see where you came from and were you actual are, as well as the track that you followed to come to your actual position. As long as you move, the system can also calculate the direction in which you move, by comparing subsequent positions. If you project your direction over a longer distance, you can even see where you are heading. This seems maybe rather abstract, but with some smart extra possibilities of the internal program and only some external buttons for the user, you can indicate waypoints or save waypoints at specific points along your track, which facilitates navigation. You can also plan ahead and create a Route, along which you want to do a future travel. It would be of great help if you were somewhat familiar with the different GPS Terms. In normal circumstances you will use these techniques with a (topographic) map of the region where you want to travel (drive, hike, walk), but in emergency situations you can very well use it to your advantage, even if you do not have a map. At least it will prevent you from walking around in circles. The more you exercised with your particular GPS receiver, the more you will be able to get out of it. Wouldn't it be nice to have maps incorporated?To a certain extend, yes. Here is where mapping GPS receivers come in, but this is not perfect. First, the maps used in these receivers are in proprietary format, which means that you can only use Garmin maps in Garmin receivers and Magellan maps in Magellan receivers, etc. Second, for two thirds of our planet's surface, you will not find maps in these formats. And third, it is wiser to have a GPS receiver AND a good paper map for your trip in unknown territory. After all, electronics can break down and the batteries can get discharged. On the other hand you can always use a mapping GPS receiver as a non-mapping receiver, without background map. Other possibilities to apply GPS NavigationBefore we continue, let us be clear about one aspect. Most of the above mentioned mapping and non-mapping dedicated GPS receivers are waterproof and rather ruggedized. This means that they are the devices of choice for a tough hike in mountainous territory and/or in bad weather. Modern pocketPCs and Palm PDAs have fast microprocessors and a lot of internal memory and have expansion slots for CF and/or SD memory cards. With the right GPS Software, you can run all kind of GPS Navigation applications on these devices. They can get the GPS information from several different sources (See also page on GPS Types): 1) The above mentioned dedicated GPS receivers can almost all output the GPS information via NMEA-0183 sentences. A cable between such a GPS receiver and your pocketPC allows you to run many GPS programs. You can use your own scanned maps or maps downloaded from the Internet, in areas for which your dedicated mapping GPS receiver does not have maps. And when none of your programs has maps for the area you are in, you can always use your dedicated GPS receiver to do Blank Map GPS Navigation. But carrying two devices, connected by a cable is often a burden, especially when you have to take them out of your car and reinstall them several times a day. You know that if you do not take them out when you leave the car, they will be stolen. 2) GPS Mice, aka "Smart Antennas", are complete GPS receivers without a user-interface. They are also connected to your pocketPC by a cable and get their power from the pocketPC, but you can not use them independently, without the pocketPC. 3) Bluetooth GPS receivers have the big advantage that they connect with the pocketPC without a cable. The disadvantage is that you have two independent devices, each with its own battery, which need to be recharged. Setup of a BT connection often is more troublesome than a cable connection. 4) GPS receivers in the form of an extended CompactFlash(CF) card make that the pocketPC and the GPS receiver form one unit, but you have to sacrifice a CF slot. If it is the only slot for storage cards in your pocketPC, where will you store your maps? GPS receivers in the form of an extended Secure Digital(SD) card have the same pros and cons. Before buying one you should verify that the SD slot is capable to handle a GPS receiver. It needs to have SDIO capability. A very practical GPS Navigation solutionPocketPCs with incorporated GPS receiver have it all. No two devices, no cables or other communication links and most have a SiRF Star III GPS chip, which is considered as one of the better, if not the best, on the market today (See article pocketPC GPS Navigation). And if you really want an all-in-one device you could opt for a pocketPC phone with incorporated GPS receiver, like the ETEN G500 or the Fujitsu Siemens LOOX T830. Passive GPS NavigationPortable car GPS Navigation systems like the TomTom Go Series, Navman iCN Series and others apply GPS Navigation in their internal programs. Together with their maps and street database, they are able to guide you from A to B, according to your preferences. But we can not say that the user applies GPS Navigation to find his way. Most users probably know nothing about navigation and certainly not about GPS Navigation. As long as you stay on the road, these devices do a wonderful job to guide you from one destination to another. But as soon as you leave the paved road, they will tell you "Go back to the road". However, you should be well aware that they still know exactly where you are, but your position does not correspond with information in their database anymore. This means that in case of an emergency, you can always switch them on, wait for a good GPS fix and go to a page called "GPS" or "Satellites" or similar and you can read your position. If you are lucky enough to have cell phone coverage, even if your cell phone does not have a GPS chip, you can still communicate your position to the competent services, who will apply GPS Navigation to find you rather fast. On pocketPCs you can run AutoRouting software like TomTom Navigator, Destinator, CoPilot Live, MapSonic, Route 66 and others. They do the same great job as the dedicated devices, with the extra advantage that for off-road usage, you can run other programs that allow you to do real GPS Navigation to find your way in the middle of nowhere. More and more cell phones are equipped with a GPS chip and more and more phones allow you to use the GPS information, other than for E-911 services alone. If the GPS chip in the phone supports Assisted GPS (A-GPS) and the cell phone carrier offers this service, the GPS reception will be superior to all the above GPS solutions. The Time-to-first Fix (TTF, the time it takes the receiver to calculate a valid GPS position after it has been switched on) will be reduced to only a couple of seconds and it will be able to capture GPS signals where others let you down. For example in narrow streets with high buildings or in dense forests. Most of the above AutoRouting GPS Navigation software for the pocketPC can also run on modern cell phones. In this case the phones will need a storage card to load the maps. But there are also services that load the maps from a server via data communication with the phone. The big advantage is that you will always have the most up-to-date maps and do not need huge storage capacity on the phone. Of course you will have to pay for this service. Active GPS Navigation for cell phonesIn May 2005 Sylvan Ascent Inc. launched the TopPhone GPS topographic mapping software for the US. It provides detailed USGS Topographic maps, and all the usual GPS capabilities such as waypoints, trips and routes. The maps are downloaded automatically into your phone as needed. Maps are stored for later use, so TopoPhone can be used even out of cellular range. In June 2006 Augmentra Ltd has released ViewRanger, its off-road GPS mapping, navigation and information application, for the latest Symbian V9 S60 3rd Edition mobile phone handsets, such as the Nokia N80, 3250 and N91. ViewRanger uses Ordnance Survey Landranger (1:50 000) maps for the UK. GPS TrackingWe already saw that the combination of a GPS receiver and cell phone technology (A-GPS) offers a better solution than GPS alone. These two technologies also make it possible to track a device with a GPS receiver and a cell phone modem in the right combination. See GPS Tracking Explained. Other Positioning SystemsGPS can not do all the positioning tasks alone. Sometimes it needs the help of other technologies and in yet other cases only other technologies can do the task. See Different Positioning Systems. GPS ExercisesFor those who would like to experiment a bit with active GPS Navigation we have made some basic GPS Exercises to get you started. After these you can enjoy the modern Treasure Hunting, called GeoCaching. More InformationThere is much more to GPS and this site covers a lot more. We invite you to have a look in the NavBar at the top left of every page and look for subjects that might interest you. Under the button New Articles you will find articles that could be of importance for you. And if you want to be informed about the latest developments in the field of GPS and wireless technologies, you will find even more on the GPS/GSM News page. Disclaimer We have done the utmost to present all information on this site as accurate as possible, but as we depend on so many different sources for this information, we shall have neither liability nor responsibility to any person or entity with respect to any loss or damages arising from the information on this site. We advise you to double check with manufacturers or retailers before deciding to purchase a product and especially a chain of products i.e. a GPS receiver plus a pocketPC plus certain software or maps and we invite you to contact us in case that you should discover something incorrect in our information. copyright © 2003-2008 GPS-practice-and-fun.com All Rights Reserved
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