When we use our mobile phone we may check whether its battery needs a charge but it’s unlikely we consider the power requirements of the site that provides the mobile service. But for operators, power consumption of their equipment has a significant financial impact. With a looming climate crisis, there is also greater emphasis on reducing the environmental impact of providing a service.
The UK telecoms provider BT has recently taken steps to go green at one of its rural cell sites. Solar panels and a wind turbine provide renewable energy and, on dark and windless days, a generator using green fuel kicks in once the battery runs dry. Vodafone has also removed the need to connect one of its cell sites in Wales to the power grid by using locally produced renewable energy.
Hrvatski Telekom in Croatia has gone one green step further by installing a wooden cell tower. The 40 metre tower is made of processed durable, fire-resistant wood. This recyclable material has a much smaller carbon footprint than steel and has a smaller aesthetic impact on a rural landscape.
You and your colleagues can also go green by studying PTT online courses instead of travelling to a classroom-based training site. The PTT catalogue includes a wide range of courses covering the technologies that underpin telecommunications services.

Mobile service providers face the challenge of providing sufficient capacity for high numbers of users in busy urban areas. Mobile users compete for access to the shared bandwidth of the radio signal that provides service coverage in an area. The greater the number of simultaneous users in a cell, the lower the online speeds available to each.

One solution is to provide extra, smaller cells in areas where large numbers of people congregate – shopping centres, sports arenas, and busy high streets, for example. Since the coverage area of these cells will not stretch further than a few hundred metres, their miniature mobile antennae can be installed relatively low down on street furniture such as lamp posts or even redundant phone kiosks.

The UK mobile operator EE has recently installed several thousand small cells in towns and cities around the UK. Busy tourist spots in rural areas can also benefit from small cell deployment. The EE small cells use either 4G or 5G technology with download speeds of 300 Mbit/s or 600Mbit/s respectively – high enough to satisfy even the most demanding of users.

These EE sites operate at radio frequencies (RF) of 1800 MHz, 2.5 GHz or 3.5 GHz. But operating at even higher frequencies could provide yet faster download speeds. Vodafone has recently carried trials of 5G cells operating at radio frequencies of tens of gigahertz (GHz) in the so-called mmWave band. These trials provided download speeds of 4 Gbit/s at a distance of 100 metres from the cells’ antennae and 2.4 Gbit/s 400 metres away.

The UK regulator Ofcom is planning an auction of mmWave frequencies for mobile operators. So, city users could have access to commercial mmWave services in the near future.

PTT offers online courses covering mobile technologies and services including an Introduction to mobile systems, 4G and 5G radio access networks, and Advanced mobile systems.

In 1991 the first commercial GSM mobile service was launched in Finland heralding a revolution in how we communicate. This second-generation service was the first to use digital technology providing a far superior performance than existing (1G) analogue services. The GSM standard developed by the European Telecommunications Standards Institute (ETSI) soon became accepted as a global standard for mobile communications.

By the early 2010s, GSM had reached a peak in terms of global coverage and calls made, with 90% market share. Since then, the number of calls made using GSM phones has decreased with less than 1% of calls made in the UK now relying on 2G coverage. With the increase in coverage of 4G and 5G services, many countries are planning to turn off their 2G and 3G services, with Australia being the first to be without 2G in 2018.

However, this 33 year old technology still has some life left in it. Even in developed countries such as the UK, 4G covers just 95% of the landmass leaving many with just 2G or 3G coverage while in Africa just 50% of the population has access to a 4G service.

Another reason for a delay in the shutdown of GSM transmissions is their use for machine to machine (M2M) communications. Smart meters often rely on 2G coverage for the transmission of electricity and gas consumption data. The automatic vehicular emergency call service eCall in Europe also uses GSM to call the emergency services in the event of an accident.

It is anticipated that GSM services will be turned off in Europe by 2035 but until then this venerable but reliable technology will have outlasted 3G and will continue to play an important part in modern communications. So, three cheers for 2G.

PTT has also been in operation for over thirty years and offers online courses covering telecommunications subjects including an Introduction to mobile systems, 4G and 5G radio access networks, and Advanced mobile systems.