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Whilst many digital signage installations are in shopping malls and other sites where broadband internet access is readily available, a growing number are not. Providing up-to-date content to these sites has been a real challenge – but mobile phone networks offer a growing range of options for the fast transmission of data. A new cellular technology, which will be available in a year or two, will make it possible to offer high-quality, live streaming video over the cellular network.

The current state-of-the-art technology for cellular networks is 3G or 3rd Generation, a family of standards offering data rates up to 14Mbit/s (mega-bits per second) on the downlink (from the cloud to your device) and 5.8Mbit/s on the uplink (from your device to the cloud) – not too different from wired broadband internet connections. The next step is 4G (or LTE – Long Term Evolution) which provides peak rates of at least 100Mbit/s down and 50Mbit/ up. LTE is about three years away – there are expected to be 200 live LTE networks around the world by 2015.

The first step for any operator contemplating using cellular communications to network a digital signage site is a survey to determine the quality of the signal available. The Ofcom website provides coverage maps for 3G which make a great starting point. There are four 3G networks in the UK, and they each have slightly different coverage patterns which may help. It is fair to say that 3G coverage is not comprehensive in the UK, though most major conurbations are now well covered.

Each of these networks is now heavily promoting wireless broadband products based on USB dongles. Tempting as they are, these products were not designed for unattended use. There are specialist cellular communications hardware platforms that are designed for the job, and will provide a guaranteed level of availability and quality of service subject to the network being present. They are also highly fault tolerant, and respond intelligently to issues like power failure, network failure and data corruption without the need for a site visit.

Once 4G or LTE becomes widely available, it will significantly extend what's possible on an 'untethered' DOOH system such as an information point. For example, video content need no longer be stored locally, as it can be delivered from the cloud on demand. To benefit, you need to ask two key questions of your wireless hardware supplier to ensure that your system is 4G ready: Will your existing 3G module connect to a 4G network and at what speed? How much redesign of the system will be involved to upgrade to a full 4G module? A little forward planning now can ensure that you are ready to benefit from the change when it comes.

Andrew Pockson is the divisional marketing manager for machine-to-machine technology company Anglia M2M.