Spectrum for development Publications
Crest Factor Reduction of an OFDM/WiMAX Network
African countries lag behind the rest of the world in their use of Information and Communication Technologies (ICTs). To reduce the digital divide quickly and cost-effectively, wireless networks are considered. WiMAX (Worldwide Interoperability for Microwave Access) is a wireless broadband access technology that uses Orthogonal Frequency Division Multiplexing (OFDM) which is a multicarrier modulation scheme. OFDM presents a problem of a high crest factor or Peak to Average Power Ratio (PAPR). To circumvent this problem either High Power Amplifiers (HPAs) with large dynamic range or PAPR reduction techniques are used. The former scheme increases cost of the system while the latter introduces redundancy or distortion. A novel PAPR reduction scheme is presented. It is a combination of the ideas of Tone Reservation and Selected Mapping. The advantage of this scheme is that it has a lower complexity. It is simulated for a WiMAX system.
Spectrum use in Latin America: Summary report of the case studies of Argentina, Brazil, Colombia, Ecuador, Peru and Venezuela
In Latin America case studies were done in Argentina, Brazil, Colombia, Ecuador, Peru and Venezuela. This report reviews and summarises the most relevant aspects of these studies.
Digital broadcast migration in West Africa: Ghana workshop report
The Ghana analog to digital migration workshop brought together almost 40 key stakeholders from the different sectors and provided them with key information of the mandated migration and educated them of the urgency, consequences, cost and strategies that could be taken during this initiative.
Spectrum for development
When talking about affordable, ubiquitous access to communication in developing countries, wireless technologies offer the most hope for effectively bridging the digital divide. This paper examines its challenges and opportunities.
Open spectrum for development: Brazil case study
For about 75 years up to the sixties, nearly all telecommunications services in the country were in private hands, distributed among hundreds of local operators. Telephony authorizations were issued and controlled by the state governments. In this process Companhia Telefônica Brasileira (CTB, a subsidiary of the Canadian company Brazilian Traction) emerged as a major operator of local and long-distance services in the majority of the larger Brazilian cities, covering about 80% of the telephone terminals in the country. CTB shared the market in these cities with Companhia Telefônica Nacional, CTN, an ITT3 subsidiary. The remaining cities and towns were covered by small local operators in extremely precarious situations.
Open spectrum for development: South Africa case study
Prior to 1994, spectrum in South Africa was managed by the state body responsible for its implementation. Thus broadcast spectrum was managed by the South African Broadcasting Corporation (SABC) and telecommunications spectrum managed by the state telecommunications provider, Telkom. This was generally uncontentious because, prior to the rise of mobile telecommunications and wireless broadband, the availability of spectrum significantly exceeded its demand.
Open spectrum for development: India case study
Spectrum management and regulation is the collective responsibility of more than one body in India. There are different bodies handling spectrum licensing, regulation, pricing, and the levy of penalties; some bodies have only an advisory role.
Open spectrum for development: Policy brief
This policy brief by Evan Light provides a brief history of how spectrum use has developed over the past 80 years, examines how it is currently being managed and what the current issues surrounding spectrum are, and makes a case for open spectrum.
Open spectrum for development: Nigeria case study
With hundreds of telecommunications and broadcasting licenses granted since 1992, Nigeria is arguably the leading country in Africa with respect to spectrum deregulation and licensing. There are over currently 350 licensed broadcast stations in operation in the country. Simultaneously NCC has licensed over 300 telecoms licenses to private companies in Nigeria, though unlike for broadcasting, this study could not independently verify the utilization of these licenses. With the global trend that will see the two regulatory bodies merge, this report questions which regulatory body’s practice of assignment will prevail, and what steps will be taken to improve transparency and usage of spectrum – especially of the newly-freed broadcasting frequencies from digital migration.
Open spectrum for development - collected research and articles
APC’s open spectrum initiative aims to provide an understanding of spectrum regulation by examining the situation in Africa, Asia and Latin America. The timely research coincides with the rapid growth of wireless and mobile in Asia, Africa and Latin America, and raises fresh questions about the use of spectrum and the policies that govern it. The research looks at how spectrum is assigned, who assigns it, and what policy or regulatory framework they use.
