GSM Is About More Than Just Mobile Phones
GSM signal processing is commonly associated with mobile phones and other devices, but what most people don't know is that it has numerous applications in the field of open source electronics. In addition to letting devices interact with existing cellular networks, GSM provides a wide range of opportunities for those interested in developing and operating their own proprietary devices.
Arduino lovers, for instance, are no strangers to using GSM for purposes other than its intended capabilities. Many custom projects powered by Arduino modules and use GSM communications to control various independent modules.
Security devices, for instance, can be implemented featuring GSM capabilities that permit central control of door locks, alarms and safety devices. You can scan multiple sensors and monitor numerous security cameras at once, gathering data in close to real-time.
Similar gains are made in the field of home automation, where it's possible to use a GSM or DTMF signal to open doors and gates automatically. Another cool use is that you can control an entire custom system, operating everything from heating, saunas and lights before you ever get in the door. GSM-enabled devices make it simple for custom electronics designers to fully automate their personal living spaces. Emergency systems and home wide master systems like water inlets and fire sprinklers are also easier to control and monitor effectively.
Of course, those whose devices see time out in the field enjoy GSM capabilities as well. Standalone GSM modules and Arduino shields with GPS capabilities make it easy to build navigation circuits that help you track your autonomous devices remotely. Suddenly, exploring the world becomes a whole lot easier and a lot more fun because you don't have to perform manual analysis of position data.
One of the most useful factors of GSM communications is that its low (1-2W) power limitations mean that you can easily perform intermittent communications without draining your battery too much. Many autonomous device cookers prefer this technology to other communications because the combination of low power requirements and long ranges (up to 35km) make operating custom devices much easier.
By far, however, the most often overlooked advantage of GSM technology is that it allows you to create devices that talk to each other without hampering other vital processing functionality. In addition to controlling machines using an Arduino unit, you can create networks of independently operating devices that modify behaviors based on sensor input. If one of your roving camera bots detects something you'd like to examine more closely, for instance, it can signal a friend to come and help investigate from a different angle.
This approach is much more efficient than sending all the data back to a central unit and waiting for a response. Although there will definitely be times when it's good to maintain central control, there are many situations where autonomous operation is far more desirable. The example of having a roving network of camera bots may seem a bit far-fetched, for instance, but the same idea can be implemented with stationary security cameras in a rent a car lot equipped for facial recognition or even plain old motion sensing.
The advantages of using GSM technology for these types of applications lies in the fact that your resources are usually limited. More often than not, you're going to have to spread your processing power around and limit your power usage to create viable device implementations. If you want to process a lot of data, it's easier to do so by having each data gathering unit perform some of the work and consult with its peers via GSM signals before sending it all upstream. This method is not only more logical to implement in the field where resources are limited, it also bears the benefit of being faster.
Perhaps you're just creating a hobby project because it's interesting and you don't have such limitations. GSM shields for Arduino can still be quite useful. Because they are designed for mobile applications, they are generally quite able to work with electret microphones and audio data. This makes interesting applications in the field of nature observation that use microcontroller devices to track and monitor animal patterns by sound possible. It's also easy to set up your own private GSM network for use in hobby sports like paintball or war-games. To the modern hardware cooker, GSM capability is indispensable.