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With broadband having been identified as a key social
and economic driver, initiatives to expand broadband access
in rural areas have been in the spotlight recently. A new
method for enabling such access is called TV white space
technology. This refers to the use of unused spectrum in
the TV spectrum bands. The CSIR Meraka Institute has been
allocated a test licence by the Independent Communications
Authority of South Africa (ICASA) for the first TV white
space technology trial in South Africa in January 2013,
in partnership with Google, TENET, WAPA and eSchools.
During the first trial, 10 schools in the Cape Town area
will be connected to one base station at Tygerberg Hospital
from January to June 2013. A second project for TV white
space trials is planned in Limpopo near the University of
Limpopo’s Mankweng/Turfloop Campus from April next
year.
“What we refer to as TV white spaces are unused spectrum
in the TV spectrum bands between 470 MHz and 790 MHz in
Region 1 of the International Telecommunications Union (ITU)
at a specific geographical location. TV white space technology
is promoted as a mechanism to achieve rural broadband using
automated, but managed spectrum allocation for secondary,
low power communication in the TV bands. This provides for
better propagation characteristics than in the GHz frequency
bands,” explains Dr Ntsibane Ntlatlapa, manager: networks
and media at the CSIR.
The white spaces could be used for alternative wireless
communication services at that location. The number and
exact frequency of unused spectrum vary from location to
location and could also vary with time.
“With current technologies, operators tend to concentrate
only on the urban or commercial areas, while innovation
is really needed in the rural areas that will always be
left behind if efforts are not made to improve their infrastructure,
as well as to provide them with opportunities to keep abreast
of developments,” says Ntlatlapa. Larger numbers of
unoccupied TV spectrums are available in low population
density such as in rural areas. This makes this spectrum
of particular interest for operations in rural areas where
the population is normally unserved or underserved with
broadband access.
TV white space (spectrum) devices deliver improved wi-fi-like
systems for broadband and are based on a combination of
spectrum sensing, geolocation and beacon techniques for
interference avoidance. These frequency bands are attractive
to potential broadband users for the following reasons:
- The large number of spectrums available that can be
used to provide connectivity;
- Propagation qualities that provide for non-line of
sight performance and in-building penetration; and
- Larger coverage areas due to the long-range propagation
of signals at these frequencies.
The CSIR will coordinate the trials; conduct research and
evaluate the technical parameters and performance of the
technology in the South African context; create and stimulate
opportunities for South African industry in related fields;
develop technology in collaboration with the CSIR and industry;
and build the spatio-temporal spectrum database.
“We are confident that these trials will influence
regulation and further broadband reach to benefit the country
and its communities,” concludes Ntlatlapa.
Enquiries:
Dr Ntsibane Ntlatlapa
nntlatlapa@csir.co.za
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