If you want to bike in unknown regions without stress and without having to read complicated roadbooks or study maps, you need a GPS device. Nowadays portable devices are available in all shapes. They use the US-American satellite system called Global Positioning System (GPS). To use GPS navigation on your bike, you need:

• A device containing the following components:
    - A GPS receiver to receive satellite signals.
    - Memory space for digital maps.
    - An interface to transfer maps and routes from your computer.
    - A software which calculates your position and the route in reference to the digital map.
  - A screen to display the calculated data and the map.
• A software to plan your routes on the computer and to generate GPS tracks.
• Digital maps.

Here you find a comprehensible guide that helps you to select the appropriate equipment:

• Common GPS Knowledge
• GPS Receivers
• Navigation Systems
• Planning Tours on the Computer
• Maps
• How Do I Plan a Tour? An Example

Common GPS Knowledge

GPS is used to determine your position on the planet with the help of satellites. It was developed in the 1970s by the US Army. Since 2000 it can be used by civilians. The accuracy lies roundabout at 7.5 yards (7 meters). Currently about 30 satellites are up in the Earth orbit, sending their current position and the exact time constantly. From these signals a GPS receiver can calculate its own location on the Earth. The orbits of the satellites are arranged in a way that you can always receive the signals of at least 4 satellites (which is the minium requirement to calculate your position) everywhere on Earth.

To make satellite navigation more useful (7.5 yards accuracy is not really overwhelming) the so-called pseudoranging method is used. By determining and comparing the delay of mutliple satellite signals the accuracy can be increased to 1 yard. The more satellites you can receive, the more accurate the measurement will be.

GPS Receivers

In order to evaluate satellite data and calculate the position, a GPS receiver is required. Here's a description of the functional principle of such a device.

• Usually the GPS receiver is already built into the device you want to use for navigation. Such devices are tailored for outdoor navigation and mostly have no other functionality.
• There are smartphones with built-in GPS receivers. However, the batteries will be drained very fast when you turn on GPS, and the built-in GPS receiver is not very accurate. The advantage is that you can also make phone calls and do other things with those devices.
• You can also put together an individual GPS solution. What you need is a so-called GPS logger whose only purpose is to receive satellite signals, calculate your position and transmit that data via bluetooth to a device (mobile phone, PDA, etc.). On the device you need a software which can utilize the position data and display a digital map. This way you can choose from a wide variety of mobile devices which you could also use for other purpose (e.g. making phone calls or internet access).

Navigation Systems

Standard GPS Devices

GPS devices are made for outdoor use. They usually are quite robust, reliable, water-proof and you even can mount them to a handlebar. The battery lasts for many hours (roundabout 20 hours). However, for tours lasting several days you should mind that the batteries are not built-in and can be changed. Ideally you can use standard batteries, so you don't have to buy special expensive spare batteries if you go on a long tour.

The only disadvantage of such devices is that the producer wants to make lots of money by selling their maps. Originally it was not intended to use free digital maps (like OpenStreetMap) on such devices. Even if the GPS device itself is not too expensive, you still have to pay a lot of money for the original maps. Which often leads to people not even considering to buy such devices.

However, a couple of enthusiastic GPS geeks managed to circumvene this obstacle by reverse engineering the GPS map format. This allows you to download free maps from the internet and install them on the GPS device. Free maps are available from OpenMTBMap, for example. By constant improvement via the community these maps are meanwhile very detailed and accurate. Often even more detailed than the original maps.

Market leader for such GPS devices is the company Garmin, and that's for a reason. Garmin offers a wide variety of high-quality outdoor GPS devices, even if the included software is a nightmare. Good and yet reasonably priced devices are for example the Garmin eTrex 20, eTrex 30, eTrex Vista HCx or eTrex Legend HCx. Some older devices do not have enough memory so you have to enhance them with a 2 GB memory card.

GPS Logger With Separate Device

If you feel the need to choose your mobile device individually and if you love to tinker around with technology and software, you could try this solution. GPS receiver and mobile device can be selected separately according to your personal needs. The disadvantage of this solution is mainly that it is not built for outdoor use and is a little complicated. While the GPS logger is not really a problem (you can carry it in a bag or your backpack), you have to protect your mobile device from water and shocks. Therefore you have to create an own solution for mounting it to the handlebar.

What you have to consider with the GPS logger is that it has good reception values. A low-quality GPS logger will not calculate the position accurately enough and will suffer from major deviations, especially in terrain with bad satellite reception. Also the battery power is an important criteria, and of course the possibility to use standard batteries. The logger should support bluetooth so it can connect to the mobile device without needing a cable. Some devices even have a motion detection sensor which turns the devide off when it does not move. This feature saves battery power. Most GPS loggers are equipped with standard mobile phone batteries. If you go on a journey lasting several days, you may need a recharging device and enough spare batteries. Standard batteries often are not supported.

Very good GPS loggers are available from companies like Wintec, Navilock, RoyalTek, QStarz, Holux, Transystem. In the end you have to decide for yourself which features are most important for you.

If you choose a mobile phone/smart phone/PDA, make sure that the device has high battery power and is able to run the navigation software you need. It also should have an offline mode where you can turn off mobile connection to save battery power. A screen resolution of at least 240x400 pixels is recommended, and of course bluetooth support. You could even use such mobile devices to make live-blogs for the internet during the journey.

With a Java-based navigation software like MapNav or TrekBuddy you can use any Java-enabled device, which means you can choose from a wide variety of devices. This software works with any digital map. The configuration of the mobile device however is rather complicated.

Mobile Phones With GPS

Today, such devices are not really qualified for outdoor use and are not recommended. The basic idea of building a GPS receiver into a smart phone is not bad, but it fails because of too much power consumption and bad quality of the GPS receiver. If you try to use such a device in the Alps, you're screwed.

Planning Tours on the Computer

In order to load a route onto a GPS device, it first has to be planned and created with an appropriate tool. The default format of digital tour data is called GPX track. There are a lot of applications available to plan tours and create GPX tracks on the computer. There are free web-based applications, tools from companies who offer digital maps, and even professional applications who offer much more than you'll ever need for outdoor route planning.

I prefer using the free web-based internet tools, like GPSies.com. There you can prepare your tracks worldwide quite comfortably based on different available maps like OpenStreetMap, OpenCycleMap, Google Maps or Google Earth. The advantage is that you can switch between maps during planning. A similar service is offered by Outdooractive.com which uses a little different maps. To plan your routes offline you should use the digital maps of the Austrian company Kompass, which include a planning tool. Their maps cover Southern Germany, Austria, Southern Tyrole, the Balearic Islands and the Canary Islands. The digital Kompass maps often deviate a little from reality. OpenStreetMap, OpenCycleMap and especially the satellite images of Google Earth and Bing Maps (Microsoft) are more accurate. If you want absolute accuracy you can plan the route using Kompass and then revise it with other tools like described below.

Maps

Thanks to digital tour planning you now have a track which you can upload into your GPS device. In theory, you could go out and get started right away. However, you'd only see your track as a line on an empty background. You would be able to see in which direction you have to go and where to take a turn. But it would be more helpful for orientation if you had a map on the background. For this purpose you can also upload a digital map to your GPS device.

You can find appropriate digital maps at VeloMap or OpenMTBMap who offer very detailed and accurate maps of many countries on the Earth for free. These maps are based on the free maps of OpenStreetMap, which is constantly improved and updated by the internet community. The maps can be uploaded with a free Garmin software (MapSource or BaseCamp), which comes with the GPS device.

Most important for your trip is an accurate GPX track and a good GPS reception. The map on your device just has the purpose to help you with orientation. For big-scale orientation you should always carry paper maps with you.

How Do I Plan a Tour? An Example

In the Alps usually a single path leads up to the summit which is very well labeled. You do not really need a GPS device for that. However, if you have the ambition to plan unpopluar routes and find special junctions because the trail may be more interesting there, or if you travel through mountains that are not so well labeled, an accurate track can be very helpful and important. Planning a route through the high mountains of the Alps is also a challenge, because different digital maps have different quality, advantages and disadvantages.

You perform preliminary planning using a digital hiking map, if possible. Ideally it would be a Kompass Digital Map. If no digital hiking map is available in that region you can also use a paper map, but then you have to try to reproduce your route as accurately as possible on the computer. The advantage of a hiking map is that every little path is marked. The disadvantage is that not all of these maps are GPS-aligned. Which means, you have to revise your track afterwards.

The second step is to revise your route. An appropriate tool can be GPSies.com. If you already have created a GPX track in the first step, you can now import it into GPSies. Otherwise you have to reproduce the route as exaclty as possible. You will notice that hiking maps deviate slightly from the internet maps. You should correct the deviations. Some paths in hiking maps may not be marked in OpenStreetMap yet. That's why using hiking maps in the first step is an advantage.

You now can improve your track using satellite maps. If you use GPSies you can switch from OpenStreetMap to Google or Microsoft satellite maps. Those have the advantage that they always match reality exactly. At a high zoom level you can improve your track further and correct paths that were not marked in OpenStreetMap. It even may be possible to evaluate the quality of the road. Most tracks are visible on satellite maps, except when they lead through dense forests or are covered by clouds.

In the high mountains of the Alps and in very steep terrain it can be useful to get a three-dimensional view of the terrain using Google Earth. The GPX track can simply be imported in Google Earth. You then can follow the track on a three-dimensional map and get an idea of the inclines and whether or not a difficult path may be drivable.

© Gletschersau, 2009-2010