Brazil. The GSMA announced the results of a new study by consultancy ATDI, which examines ways to mitigate interference between new mobile services using LTE technology and existing TV services. In October, Brazilian regulator ANATEL made the decision to allocate the Digital Dividend for mobile services and adopt the Asia Pacific Band Plan (APT).
Projections indicate that using the 700MHz band for mobile broadband will generate substantial socio-economic benefits for Brazil, contributing an additional US$1.4 billion to GDP, creating more than 4,300 job opportunities and generating additional tax revenues of US$1.3 billion through 2020.
The report focused on the cities of Brasilia, Campinas and São Paulo, because they will probably be some of the areas where potential interference in the reception of television signals and mobile services may present the biggest problems. Potential interference problems should be less acute in other areas and therefore easier to mitigate.
Compatibility with analog television signals was also included in the equation due to long-term plans for their conversion to digital signals. As digital television in Brazil uses ISDB-T technology, this study is also relevant to other markets, including Chile, Costa Rica and Ecuador, where the Spectrum of the Digital Dividend has also been allocated to mobile services.
Among the main conclusions of the study, the following stand out:
- The affected population in general is small, and can be reduced by applying the appropriate mitigation techniques in the potential areas of interference. For example, in Brasilia and Campinas, the population that could be affected is less than 10,000 people, and through mitigation the problem can be virtually eliminated;
- The application of filters for both ISDB-T TV signal transmitters and for LTE mobile service base stations could help significantly reduce the likelihood of out-of-band interference and signal blocking;
- The probability of interference between direct consumption LTE devices, such as smartphones and tablets, by the ISDB-T TV system from blocking and out-of-band broadcasts is very low; and
- Adopting plans that avoid high-power broadcasts on higher television channels (especially between channels 48-51) will facilitate coexistence, since interference is more likely to occur the smaller the separation between THE TV spectrum and the LTE spectrum.
