Posts Tagged ‘fleet management’

Features of Global Positioning Systems - GPS

Monday, March 17th, 2008

GPS (Global Positioning System) receivers not only provide the location of vehicles say with fleet management tracking if you have delivery trucks or taxi cabs or maybe you want to keep an eye on the driving habits of your teenager, these receivers also provide other valuable and important information. Such information includes the time, location, speed, direction of travel, stored locations and the ability of course to cumulate all of this data to use it over the long term.

Now a little more detail on each type of information received by the GPS receivers. With respect to time, a GPS receiver receives time information from atomic clocks, so it is much more accurate than your average bedside clock for example.

A GPS unit provides your location in three dimensions which are latitude (x coordinate), longitude (y coordinate) and elevation. The vertical (elevation) accuracy of consumer GPS receivers is not usually that great. It is usually accurate down to 15 meters or 49 feet, 95% of the time. Some GPS units are fitted with more accurate barometric altimeters for better elevation information. Also the location can usually be displayed in a number of coordinate systems such as latitude/longitude and UTM (Universal Transverse Mercator).

With speed, this is basically how fast the vehicle is travelling and paired with this is the direction that the vehicle or person is traveling towards. Note however that if you are stationary, the GPS unit cannot use satellite signals to determine which direction you are facing but instead would use an internal electronic compass to provide this information.

Stored locations are exactly as the phrase suggests which is the ability to save on the GPS receiver the locations which you were at previously or want to go to in the future. These location positions are called waypoints and a collection of these waypoints which is used to plot a course is called a route. Finally is the great use and benefits of cumulative data. Cumulative data can generally be summed up as collecting information on total distance traveled, average speed, maximum speed, minimum speed, elapsed time and estimated arrival time for a particular location.

To take a quick detour and with reference to the site SecureWithGPS, the use of this accumulated data can be very resourceful for both families and businesses alike. Say for example you are a business owner with a fleet of trucks, owner of taxis or cabs or even just a concerned parent looking out for their teenagers, the wealth of information provided by this system is phenomenal. If you have your fleet of trucks, you can track the distance covered by each truck driver when you want from the comfort of your computer. No need to go to each GPS physically and obtain the data you need, it is instead all available in one simple to use interface. This is known as fleet management and further information can be found at SecureWithGPS . You can also erect a virtual fence or boundary so that when your truck drivers deviate outside of this virtual boundary you can be notified. How is this helpful you may ask? Well, very simply, it helps to reduce the use of business vehicles for personal use by your employees and as a result should reduce fuel costs for your fleet of vehicles. For the concerned parents out there, you can more easily keep track of where your children are saying that they went on that last trip versus where they actually went. Did they go to the mall or to the library and study? Did they go to a house of a friend or to the ex-boyfriend or ex-girlfriend who was causing trouble for your family?

Finally there are many other features available on GPS (Global Positioning System) units which will be discussed in another article. To mention some of these features now however are the type of displays whether monochrome, color or no screen at all also alarms, built-in maps, electronic compass, altimeters, internal memory and of course storage systems for all of this data.

Again, if you find any of this information interesting and wish to purchase or even obtain more information on the great features of GPS units you can check the website SecureWithGPS.

Types of GPS Radio Signals and GPS Receivers

Monday, March 17th, 2008

GPS satellites transmit two types of radio signals which are C/A-code and P-code. Coarse Acquisition (C/A code) is the type of signal which is used in consumer units and is known as SPS (Standard Positioning Service). C/A-code is not as accurate as P-code (which is mentioned later on) and is easier for U.S. military forces to jam and spoof, i.e. broadcast false signals to trick the receiver into thinking it is somewhere else when it really is not. The advantage of C/A-code however is that it acquires the satellite signal faster and hence obtaining an initial fix on your position takes less time. Due to this, there is an option for receivers which use P-code to track onto the C/A-code signal first then switch over to the P-code.

P-code on the other hand provides highly precise location information and it is difficult to jam or spoof. The U.S. military is the primary user of P-code transmissions and uses an encrypted form of the data so that only special receivers can access the signal. P-code broadcasts are known as the Precise Positioning System (PPS).
Now let us switch focus to that of GPS receivers. Some of this information can become pretty technical but hopefully both the novice and more advanced readers can learn and sift through the information to help them.
GPS units receive two different types of data which are Almanac and Ephemeris. Almanac data contains the approximate positions of the satellites; the data are continuously being transmitted and are stored in the memory of the GPS receiver. Ephemeris data broadcasts the precise positions of the satellites. To obtain an accurate location fix, the receiver has to know how far away a satellite is. Hence, the GPS receiver calculates the distance to the satellite by of course using signals from the orbiting satellite.
A GPS receiver needs data from multiple satellites to obtain or triangulate a position as to where the user of the GPS is located. First there is the issue of location which requires a minimum of three satellite signals. Second is that of position, which needs four satellite signals to determine your position in three dimensions: latitude, longitude and elevation. GPS receivers can generally be separated into five categories which are consumer models, U.S. military/government models, mapping/resource models, survey models and commercial transportation models. With respect to the consumer and commercial transportation models, the site SecureWithGPS provides GPS devices more catered to the consumer and commercial markets. If you think that such devices might suit your needs for fleet management of your vehicles, keeping track of the security of your car when it might be parked or even looking out for your teenage drivers, please visit the site for useful and related information.
Finally, we will take a quick look at the accuracy of GPS receivers. One can typically expect a GPS receiver to be accurate within 49 feet or 15 meters. Accuracy depends on receiver location, obstructions that block satellite signals and information received from ground-based beacons to name a few. So rest assured that after spending money to start using this widely used technology the data obtained from the GPS receivers will definitely be accurate enough to provide the user with reliable information.

What is GPS - Global Positioning System?

Monday, March 17th, 2008

The purpose of this article and hopefully other GPS (Global Positioning System) articles that I write, is to provide the user with relevant information about this technology and then if interested, allow the reader the opportunity to purchase GPS tracking systems whether for personal use or business use from a related site called SecureWithGPS.

So what is GPS you are wondering or perhaps you already know and are just looking for a refresher course? Basically, with the use of a radio receiver, i.e. a device which receives signals from the GPS satellites that orbit the Earth, you can locate yourself or the position of a vehicle for that matter anywhere on the Earth. Assuming of course, that the area you are trying to locate is covered by the GPS satellites. So in other words GPS tracking and receiving simply consists of buying a receiver, popping in some batteries, turning it on and if you have done everything right, the co-ordinates of where you are should appear on your GPS device.

One should note that there is more than one GPS system but for this article, I am referring to the Global Positioning System which is operated by the United States government and similar technology that is based on such a system. To provide a quick history, radio signals have been used for navigation dating back to the 1920s. The first step to GPS came way back in 1957 when the Russians launched Sputnik, which was the first satellite to orbit Earth. Eventually American scientists figured out that if they knew a satellite’s precise orbital position, they could accurately locate their position on Earth. The first GPS satellite was then launched in 1974 and by 1994, the full constellation of 24 satellites were in place. Hence these satellites make up the GPS system as we know it today.

Finally, one might be wondering why this technology is so widely in use or what is the big deal about it? Well, to mention a few reasons, which will hopefully be expanded on in other GPS articles, is that almost anything which has a GPS transmitter on it, it can be tracked and located fairly accurately around the world. You can attach a GPS receiver to your personal car, your children’s car, a fleet of vehicles that you may own and wish to monitor or even to locate your pet if it were to wander away and get lost. But with reference to the personal and business aspect however the website SecureWithGPS provides a great overview of what the current technology can be used for.