There is a standing joke that has been translated into many languages that tells of men possessing a genetic aversion to asking directions. Despite it being slightly prejudiced there is an element of truth that every man must face up to in their heart of hearts. Instinctual global geographical awareness is as much a trait of manhood than walking over hot coals, wrestling a rutting stag or leaving the toilet seat up.
With new satellite technology the Global Positioning Device, or GPS means that men never have to ask for directions ever again. This article examines three leading GPS models from three separate manufacturers in an impartial assessment of price against features.
The first is not technically a GPS model but a Bluetooth connection that will turn your mobile into a GPS. For 60GBP you can turn your mobile into a navigator with the Wayfinder Bluetooth GPS receiver. It is effective with quick satellite pick-up and it is compatible with any software. The issue is not the performance, but the cost. The initial outlay is reasonable however you have to pay an annual charge to avoid astronomical call costs in receiving.
The TomTom 1 is as no thrills as GPS gets. At an RRP of 150BGP which has now been dropped to 95GBP online it is by far the cheapest effective GPS system on the market. It is small, compact and accurate however the only drawback is that there is nothing beyond the GPS, so if you are looking for something more than basic destination access then this is not for you.
Finally the TomTom Go 730 is a step up in features from the 530 and a generation down from the 930. The only thing missing are the maps of North America and this combines the legendary TomTom simplicity with extra features such as Bluetooth and FM radio to keep you occupied, even your incoming text messages can be linked with GPS to be read out. The price is literally the only issue as 300GBP is a hefty price to pay for not asking directions.
Technology is changing the way in which we travel. The latter GPS model boasts advanced lane guidance which can instruct you which lanes to be in. That is pretty scary when you think about it, that satellites can monitor our every movements, however the loss of a little freedom is well worth it so long as we never have to ask directions
The Top Three GPS Models Reviewed
Some GPS Tracking Devices To Choose From When Considering GPS For Children
Many parents these days are searching for GPS for children. They are increasingly turning to technology to help them keep tabs on their kids of all ages. Most will turn to the internet to find the right device. But how can they sift through the junk to get to the right GPS tracking system? The best way for them to do this is to educate themselves on what GPS tracking devices are out there. From GPS cell phones to GPS locators in pieces of clothing, GPS devices range from the open and conspicuous to the hidden and silent. What is more is that many of these devices have two uses (dual use) and thus serve two purposes at once.
One of the most out in the open devices there is are GPS locator watches. Two of these types of GPS devices are Chitter Chatter and Wherify. Chitter Chatter one of the smallest GPS devices in the world. It resembles a wrist watch and is generally regarded to be accurate to within 300 feet. The Wherify GPS Locator Watch is, as its name suggests, a watch. However this GPS watch is resistant to water and resistant to cuts. The watch can contact emergency authorities as well as the parents if two outer buttons on the watch are held down. A very nice additional feature of this particular GPS device is that it prevents someone from removing it when its owner does not wish it. With these such devices, all a parent need to do is to log into the monitoring website and with as few mouse clicks, they can find their child.
Not to be outdone, some wireless service providers are also offering their own take on GPS tracking systems. Verizon has a monitoring service utilizing the GPS locator embedded in a cell phone. The Verizon service is called Chaperone. Sprint also has a service which is called Family Locator. One of the biggest differences between Chaperone and Family Locator is that while the Chaperone service may only be used with Verizon supplied cell phones, Family Locator can be used with any web capable phone.
Whether it is a GPS wrist watch or a GPS cell phone, these are some of more dual-use GPS tracking devices that parents can use to provide GPS for children. There are many others to choose from so parents should do as much research as they can before settling on the right GPS tracking system for their family.
GPS Vehicle Tracking
GPS Vehicle Tracking
This is particularly useful when using GPS units attached to vehicles which have distinctive identification such as chassis numbers. The same principle applies as for a GPS tracking device designed to be worn by a human, except that the GPS is integrated within the vehicular electronics.
This serves two purposes. On the one hand, it provides the driver with an integrated GPS system, without the necessity to purchase a car navigation system, or a PDA-based GPS system, whilst also offering the possibility to relay that information via a radio or cell phone transmitter.
In fact, these systems have already been tried in the field, primarily as a vehicle locator in the event that the vehicle to which the GPS vehicle tracking system is attached is stolen. The police, once informed, can find out from the control center where the vehicle is, and proceed to track it physically.
A useful consequence of being able to use GPS vehicle tracking to locate a vehicle is that the manufacturer can also use the information to alert the driver as to when they near a service center.
If, along with the GPS coordinates, the system relays telemetry information such as the status of the engine, time since the last service, or even information not relating to defects, the receiver of this information can make a decision as to what kind of alert to pass on to the driver.
GPS Tracking
In fact, it is this use which represents the simplest form of GPS tracking. The user is able, using a portable GPS device, to keep a track of where they have been, in order to be able to either retrace their steps, or follow the same path again in the future.
When combined with other technologies such as GPS phones, this also gives the possibility for other users of GPS to follow in the footsteps of the initial user; which can be a useful application of GPS tracking for field activities.
Where GPS tracking comes into its own, however, is when it is combined with other broadcast technologies such as radio. GPS watches, for example, can be fitted with a GPS receiver which is capable of calculating its position, whilst also broadcasting that using a miniature radio transmitter.
The signal is relayed to a central command center equipped with GPS software systems which can track the position of the wearer, and either store it as a path or relay that information to a third party.
That third party could be an anxious parent, or the police. In fact there are a variety of GPS phones and wristbands which are sold in conjunction with a service which enables third parties to find out where their charges are at any time of the day or night.
How GPS Works
For those who are unfamiliar with the term, GPS stands for Global Positioning System, and is a way of locating a receiver in three dimensional space anywhere on the Earth, and even in orbit about it.
GPS is arguably one of the most important inventions of our time, and has so many different applications that many technologies and ways of working are continually being improved in order to make the most of it.
To understand exactly why it is so useful and important, we should first look at how GPS works. More importantly, looking at what technological achievements have driven the development of this fascinating positioning system.
Signals
In order for GPS to work, a network of satellites was placed into orbit around planet Earth, each broadcasting a specific signal, much like a normal radio signal. This signal can be received by a low cost, low technology aerial, even though the signal is very weak.
Rather than carrying an actual radio or television program, the signals that are broadcast by the satellites carry data that is passed from the aerial, decoded and used by to the GPS software.
The information is specific enough that the GPS software can identify the satellite, it’s location in space, and calculate the time that the signal took to travel from the satellite to the GPS receiver.
Using different signals from different satellites, the GPS software is able to calculate the position of the receiver. The principle is very similar to that which is used in orienteering – if you can identify three places on your map, take a bearing to where they are, and draw three lines on the map, then you will find out where you are on the map.
The lines will intersect, and, depending on the accuracy of the bearings, the triangle that they form where they intersect will approximate your position, within a margin of error.
GPS software performs a similar kind of exercise, using the known positions of the satellites in space, and measuring the time that the signal has taken to travel from the satellite to Earth.
The result of the “trilateration” (the term used when distances are used instead of bearings) of at least three satellites, assuming that the clocks are all synchronized enables the software to calculate, within a margin of error, where the device is located in terms of its latitude (East-West) and longitude (North-South) and distance from the center of the Earth.
Timing & Correction
In a perfect world, the accuracy should be absolute, but there are many different factors which prevent this. Principally, it is impossible to ensure that the clocks are all synchronized.
Since the satellites each contain atomic clocks which are extremely accurate, and certainly accurate with respect to each other, we can assume that most of the problem lies with the clock inside the GPS unit itself.
Keeping the cost of the technology down to a minimum is a key part of the success of any consumer device, and it is simply not possible to fit each GPS unit with an atomic clock costing tens of thousands of dollars. Luckily, in creating the system, the designers designed GPS to work whether the receiver’s clock is accurate or not.
There are a few solutions. However the solution that was chosen uses a fourth satellite to provide a cross check in the trilateration process. Since trilateration from three signals should pinpoint the location exactly, adding a fourth will move that location; that is, it will not intersect with the calculated location.
This indicates to the GPS software that there is a discrepancy, and so it performs an additional calculation to find a value that it can use to adjust all the signals so that the four lines intersect.
Usually, this is as simple as subtracting a second (for example) from each of the calculated travel times of the signals. Thus, the GPS software can also update its’ own internal clock; and means that not only do we have an accurate positioning device, but also an atomic clock in the palm of our hands.
Mapping
Knowing where the device is in space is one thing, but it is fairly useless information without something to compare it with. Thus, the mapping part of any GPS software is very important; it is how GPS works our possible routes, and allows the user to plan trips in advance.
In fact, it is often the mapping data which elevates the price of the GPS solution; it must be accurate and updated reasonably frequently. There are, however, several kinds of map, and each is intended for different users, with different needs.
Road users, for example, require that their mapping data contains accurate information about the road network in the region that they will be traveling in, but will not require detailed information about the lie of the land – they do not really worry about the height of hills and so forth.
On the other hand, hiking GPS users might wish to have a detailed map of the terrain, rivers, hills and so forth, and perhaps tracks and trails, but not roads. They might also like to adorn their map with specific icons of things that they find along the way and that they wish to keep a record of – not to mention waypoints; locations to make for on their general route.
Finally, marine users need very specific information relating to the sea bed, navigable channels, and other pieces of maritime data that enables them to navigate safely. Of course, the sea itself is reasonably featureless, but underneath quite some detail is needed to be sure that the boat will not become grounded.
Fishermen also use marine GPS to locate themselves and track the movement of shoals of fish both in real time, and to predict where they will be the next day. The advent of GPS fixing has also meant that co-operative fishing has become much easier, where there are several boats all relaying their locations to each other while they locate the best fishing waters.
Special kinds of marine GPS, known as fishfinders, also combine several functions in one to help fishermen. A fishfinder comprises GPS and also sonar, along with advanced tracking functions and storage for various kinds of fishing and maritime information.
Getting Started
There are a few solutions available to consumers, ranging from sophisticated in-car GPS systems, which feature voice guiding, powerful dynamic route calculation, and the possibility to update the map from a CD.
Then there are handheld GPS devices, such as those from Magellan and Garmin, which store a map inside, and are usually designed for outdoor use. They cannot generally perform dynamic route calculation since they do not have any road information, and leave the user to find their own way from A to B.
Finally, a more recent solution has appeared on the market which uses the power of a PDA to run the actual GPS software, and uses the interface capability to attach a GPS receiver (antenna) to the unit. These tend to be the cheapest, easiest to use and most flexible solutions, but are only as rugged as the PDA to which they are attached.