Black glasses with masking tape holding them together and a pocket protector are no longer a required part of the uniform for GPS owners. GPS has gone mainstream. But if you’re still not up to date on what it is and how it works, and if you’d like some advice on what to buy, this article will bring you up to speed.
A GPS device is like a map on steroids. First of all, it always gives you that little “You Are Here” dot – you no longer need to figure that out for yourself. And all you need to do is tell it where you want to go and it will plot the course for you. It doesn’t end there, however. New GPS units will provide you with voice guided directions for the entire trip, tell you where the nearest gas station is, and will even put you back on course if you take a wrong turn.
GPS stands for Global Positioning System, a system of 28 satellites orbiting earth. It was originally developed for military use, but its uses have spread far beyond just military applications. Your GPS unit can receive signals from these satellites, and by using these signals, calculates your position (within 3-10 meters), direction, altitude, and velocity. Once your GPS unit knows where you are, it can help you get to where you’re going as long as it has mapping software installed. All but the most basic GPS devices currently have mapping software.
Now that you know a little bit about what a GPS device is and how it works, it’s time to educate yourself on the features available and decide which unit will best suit your needs. There is certainly no shortage of GPS devices available, so doing a little research can save you a lot of time and hassle.
Step 1 – Which type of GPS do you need?
There are four main types of GPS units; the car navigation system, the portable outdoors unit, the marine system, and the PDA/GPS hybrid.
If you’re mainly planning on using your GPS to get you from point A to B in your car and don’t think you’d use it for much else, your best bet is the in-car navigation system. These systems can be built in to your car or you can purchase a device that mounts onto your dashboard. Desirable features for the in-car systems are: voice guided directions; detailed built in maps; touch screens; rerouting in case you get off course; and a database with points of interest to help you find the nearest gas station, restaurant, and many more places along your route.
If you’re going to want a GPS device that isn’t limited to the car, then you may want to consider a handheld GPS (http://www.gpsmaestro.com/handheld). These devices are ideal for anyone who loves to hike or bike. Features to look for in a handheld unit are: lightweight, rugged, waterproofing, long battery life, color screens, and mapping features. The handheld GPS units are geared towards people who spend a significant amount of time outside. For example, if you’re out hiking you can easily track where you’ve been; mark your own points of interest; and even find out how far you’ve gone and at what speed. Many new handheld devices offer some navigation features while driving. You can even purchase handheld units that offer built in radios that will not only allow you to communicate with other members of your party, but will also display everyone’s location on your screen.
If being on the water and fishing is your thing then you should probably consider a marine GPS. These units are specifically designed to be on and around water. All of these units will feature waterproofing and should have screens that are easy to read even in bright sunlight. Some other good features to look for are: color chart plotters, onshore and offshore maps, fish hotspots, and sonar capability. You may also want to consider a unit that will function as your car navigator, eliminating the need for two devices.
The final category of GPS device is the PDA/GPS hybrid. This device offers a good combination of the car navigation systems and handheld devices. You’ll get the large screen that you’d find in the car system and the portability of a handheld unit. Also, you get a PDA to help you keep organized. One drawback is the limited selection of these units. Only a few companies have attempted to make an integrated unit, and all have some serious limitations.
If you are considering a PDA/GPS hybrid, I’d recommend you purchase the PDA separately from the GPS. Find a PDA that offers all the features you want in your PDA, then look for a GPS receiver that will attach to your PDA via Bluetooth. The features to watch for are the same as listed for the in car systems. All of the current PDA/GPS devices are better suited towards driving than hiking, although they do offer the portability for outdoor activities if needed. This category probably offers the most potential of the four, but it is also the newest, so watch for significant improvements in this category in the future.
Step 2 – Budget Considerations
If you’re on a budget, then it’s important to decide which features are most important to you. If you want a full featured car navigation system, it can easily run over $1000 (and over $2000 if you want one that’s built in). If, however, it would be more of a toy to play with, then a handheld device could be a better choice as they can be as low as $100 and are rarely more than $500. Marine GPS devices vary widely in prices, but a very good device can usually be purchased for no more than $1000. If the PDA/GPS devices interest you, they typically range from $400-$900.
Step 3 – Where to Buy
Finding the right store to purchase your GPS device can be difficult. Most stores only carry one or two kinds of GPS. For example, if you go to a sporting goods store you’re likely to find the handheld GPS units and marine GPS units but not the car navigation or the PDA/GPS hybrids. I actually prefer shopping online for GPS units as the prices will likely be lower, and you’ll be able to read user reviews of the items before you buy. Just make sure that if you have a problem with your GPS you are able to return it.
Owning a GPS can be extremely helpful, especially if you tend to get lost a lot or if your glove compartment is overflowing with outdated maps. They can also make planning a long trip to an unfamiliar area a breeze. Deciding which GPS to purchase can be difficult, but as long as you make a list of the features you absolutely must have then all you have to do is find the units that match your budget. Read reviews from other owners and you should have no trouble at all. Once you purchase your own GPS unit, you’ll wonder how you ever lived without one.
By: Gary Ruplinger
Archive for February, 2010
GPS Buying Tips For Technophobes
February 23rd, 2010Garmin Nuvi 660 Rated As Consumer Reports Best Buy!
February 21st, 2010
The Garmin Nuvi 660 performs well in all categories. The price point on this unit is very affordable. It has the highest overall rated very good score of all the GPS units indicating an exceptional value by “Consumer Reports”. Ratings of excellent for entering destination, information for driver, portability and color display. Ratings of very good for use of controls, routing options, routing time and mount design. All with a retail price in the $ 350.00. A tested battery life of approximately 4.5 hours, weight of 6.7 ounces, screen size of 4.4 inches, Bluetooth hands free calls (Allows the user to make and receive telephone calls using the unit’s internal speaker, microphone and screen.) and spoken street names (Commonly referred to as “Text-to-Speech,” this feature allows the driver to confirm directions with street signs without looking at the screen) It can also dial phone numbers of point of interest locations. This feature requires a Bluetooth compatible phone as well.
These results are the most current ratings from “Consumer Reports” magazine of the GPS units that are considered portable in auto GPS navigation systems. You can remove them from one vehicle and use them in another vehicle. The most recent use that I have heard of is by delivery people, which makes a great deal of sense. I have also had some very positive comments from two different older ladies about ease of use when traveling from rural areas about two hours outside a large city via much more rural roads and back without getting lost at all. This eased their minds about traveling these roads alone and getting home safely.
By: Diana Zagouris
Posted in Article
Tags: Battery Life Best Buy Compatible Phone Consumer Reports Magazine Destination Information Free Calls Garmin Nuvi 660 Gps Units Interest Locations Internal Speaker Navigation Systems Nuvi 660 Older Ladies Point Of Interest Portability Rural Roads Speaker Microphone Street Names Street Signs Text To Speech
GPS Ionospheric Delay – The Problem and Solution
February 21st, 2010
GPS ionospheric delay is one of the most common issues with the gps navigation systems. Inconsistencies of atmospheric conditions affect the speed of the GPS signals as they pass through the Earth’s atmosphere and ionosphere. Correcting these errors is a significant challenge to improving GPS position accuracy.
These effects are smallest when the satellite is directly overhead and become greater for satellites nearer the horizon since the signal is affected for a longer time. Once the receiver’s approximate location is known, a mathematical model can be used to estimate and compensate for these errors.
Because ionospheric delay affects the speed of microwave signals differently based on frequency – a characteristic known as dispersion – both frequency bands can be used to help reduce this error. Some military and expensive survey-grade civilian receivers compare the different delay in the frequencies to measure atmosphere dispersion and apply a more precise correction.
This can be done in civilian GPS receivers without decrypting the P(Y) signal carried on L2 by tracking the carrier wave instead of the modulated code. To do this on lower cost receivers, a new civilian code signal on L2 called L2C was added to the satellites. This new signal allows a direct comparison of the L1 and L2 signals using the coded signal instead of the carrier wave.
The effects of the ionosphere generally change slowly and can be averaged over time. The effects for any particular geographical area can be easily calculated by comparing the GPS-measured position to a known surveyed location. This correction is also valid for other receivers in the same general location.
Several systems send this information over radio or other links to allow L1 only receivers to make corrections. The date is transmitted via satellite system and transmits it on the GPS frequency using a special pseudo-random number so only one antenna and receiver is required.
Humidity also causes a variable delay resulting in errors similar to ionospheric delay but occurring in the troposphere. This effect is more localized and changes more quickly than ionospheric effects and is not frequency dependent. These traits make it much more difficult to make precise measurement and compensation for humidity errors than with the ionospheric effects.
Changes in altitude also change the amount of delay due to the signal passing through less of the atmosphere at higher elevations. Since the GPS receiver computes its approximate altitude, this error is relatively simple to correct.
GPS signals can also be affected by multi-path issues where the radio signals reflect off of surrounding terrain such as buildings, canyon walls, and hard ground. These delayed signals can cause inaccuracy as a well.
To correct these errors, many techniques have been developed. How these techniques work depends on addressing the long delay multi-path or shorter delay multi-path. To know more on the solution on problems with gps system, please visit GPSAutoTracker for more tips on how to maximize the use of your gps system.
By: Audrey Ly
Posted in Article
Tags: Approximate Location Atmospheric Conditions Carrier Wave Civilian Gps Receivers Code Signal Dispersion Frequency Bands General Location Geographical Area Gps Navigation Systems Gps Signals Inconsistencies Ionosphere L2c Mathematical Model New Signal Position Accuracy Pseudo Random Number Satellite System Solution Gps
