Filling in the gaps – understanding white space spectrum
Lee-Roy Chetty
2013-07-10 00:00:00

Put simply, ICTs help reinforce, converge and integrate all three key pillars of sustainable development, and also support and facilitate the attainment of its fundamental underlying principles of efficiency, effectiveness and equity.



However, challenges such as ICT infrastructure investment and development as well as ubiquitous access to broadband remain a steep hurdle to overcome in order to close the fissure of the digital divide in the developing world.



According to the International Telecommunication Union (ITU), in 2013 over 2.7 billion people were connected to the Internet. However in the developing world, only 31% of the population is online, compared to 77% of people in the developed world.



One potential solution to address the developing world’s challenges in relation to increasing access to broadband and Internet connectivity is by leveraging the benefits derived from the digital dividend and the use of white space spectrum.



The term digital dividend refers to digital compression systems available for digital television systems. This process of digital compression facilitates the transmission of standard digital television channels - or airwaves - of acceptable quality in the radio-frequency spectrum, previously used by a single analogue channel.



Typically, there are approximately four to five terrestrial analogue services in any given region. Therefore the digitisation into a single digital television channel considerably reduces the overall use of spectrum and in turn, frees up white space spectrum - which simply refers to the gaps in the spectrum band which can be used to transmit signals.



These airwaves have the ability to provide wireless broadband over white spaces through the unused spectrum that sits between broadcast TV channels without interfering with licensed spectrum.



Capitalising on white space spectrum is beneficial in myriad ways, but more imparticular due to the fact that low frequency signals can travel longer distances relatively cheaply and effectively. This technology is also, in theory, well suited to provide low cost connectivity to rural communities with poor telecommunications infrastructure which is a common challenge for developing countries – including Least Developed Countries (LDCs).



The range of users to which white space spectrum can be opened up to is vast and includes additional terrestrial broadcasting services, mobile multimedia applications, mobile communications, and wireless broadband access systems.



Proponents of this form of spectrum identify the use of white space as an opportunity to respond to the growing demand for new wireless communication services around the world.



If the digital dividend is to be utilised and fully capitalised on, frequency harmonisation requirements are a required condition. As a result, such harmonisation would create enormous benefits in terms of social impact and increased productivity. The possibility of harmonisation has and will primarily be dependent on the timing and coordination of the analogue-to-digital switchover process in various regions of the world in the coming years, which to date has been advanced in some regions but conversely, cumbersome and fraught with delays in others.



Although the use of white space has been seen as a cost-effective and potential panacea to address the digital divide in the developing world, it is critical to also understand the potential short-comings of making use of this type of spectrum.



Specifically, it is important for governments, technology service providers and indeed consumers to be aware of the impact of “last mile” connectivity in relation to white space and the additional costs and the potential bottle-necks associated with this form of spectrum use.



Last mile connectivity refers to the delivery of broadband or Wi-Fi to the end user and can also refer to technologies which may also be used for back-end infrastructure. In addition to harmonisation requirements in relation to white space, the amount of spectrum to be released in the switchover in individual countries around the developing world depends primarily on specific national peculiarities such as the geography and topography of a country, the degree of penetration of cable or satellite television services, requirements for regional or minority television services, and spectrum usage in neighbouring countries.



Therefore, the size of the digital dividend and as a result the availability of white space will vary from region to region, and from country to country.



The speed, quality and reliability of the last mile connectivity in relation to white space as well as any network congestion issues will be dependent on these variables and existing infrastructure. In addition, the fact that in its current form, white space spectrum operates in a license-exempt framework means that any number of users is allowed to share a band with no right of non-interference and no right to cause interference, which has the potential to create crippling white space bottle-necks in any system.



The benefits of the digital dividend and the existence of white space to provide broadband and Wi-Fi connectivity to the developing world is an exciting development. However, there are a number of challenges in fully preparing for the efficient and effective use of this scarce resource. Technology companies, service providers and governments should be encouraged to continue to find innovative ways to attempt to connect the unconnected, but it is also important to ensure that the correct planning, implementation and harmonization of white space spectrum is achieved before it can be seen as the solution to the developing world’s digital divide challenges.