Digital radio report

In common with other industrialised countries, the radio industry in Australia is in the midst of a significant transformation. Traditional analogue radio services, broadcasting on AM and FM frequencies, remain popular and continue to attract substantial audiences and revenue. However, the analogue platform is very mature, offering only limited capacity for technical change and development, and FM spectrum is now largely fully occupied in population dense areas. In addition, AM transmissions face growing pressure from urban development and related increasing signal interference. The Australian radio industry therefore retains a strong interest in the opportunities presented by digital radio for service innovation and future growth. To date, digital terrestrial radio services have been licensed for the five mainland state capital cities,1 and trials involving such services are underway in Canberra and Darwin. Within the mainland state capital cities, take up of digital terrestrial radio services continues to grow slowly but steadily with listenership reaching almost 25 per cent in the first quarter of 2015.2 Listenership has benefitted from increased availability of digital radio receivers in motor vehicles (a primary source of listening) and the recent additional rollout of in-fill transmitters increasing coverage of the services in Brisbane, Melbourne, Perth and Sydney. The cost and complexity of rolling out Digital Audio Broadcasting Plus (DAB+)-based digital terrestrial radio services across regional Australia3 present major challenges for the industry. The need to cover large geographic areas with small and dispersed populations offers unique challenges which have not been faced in many international markets. At the same time, Australians are rapidly adopting new types of technology with the growth of online audio platforms such as Spotify and Pandora. These services are complementing the move by traditional radio businesses—most notably the national broadcasters—to deliver radio services online or through mobile apps. The announcement by Apple of a move into the streamed audio market will only increase the choices available to audiences. These services may herald a generational change in listening habits with significant implications for traditional platforms over time. That said, there are ongoing challenges with the bandwidth and data transmission requirements of these services being delivered to large audiences over mobile and wireless platforms. The digital terrestrial radio industry is subject to a range of regulatory requirements in the Broadcasting Services Act 1992 (the BSA) and the Radiocommunications Act 1992 (the Radiocommunications Act), which govern matters such as the planning and start up of services, and the sharing of and access to the transmission multiplex in each area. Against the background of changes in the radio industry, this review considers whether changes are required to this framework to provide greater flexibility to the industry and the Australian Communications and Media Authority (the ACMA) to plan for change and ensure that the radio industry is well placed to determine its future strategies for digital services. Key issues examined by the review included: the current state of digital terrestrial radio in Australia, and the impacts of alternative technologies on the industry and listeners; whether Australia should set a digital switchover date for analogue commercial, national, community or other terrestrially transmitted radio services; what legislative/regulatory arrangements should be in place to assist the rollout of digital terrestrial radio services in regional areas; and whether changes are required to the legislative regime for digital radio, including to reduce the regulatory burden on industry

All photonic analogue to digital and digital to analogue conversion techniques for digital radio over fibre system applications

Copyright @ 2011 IEEEWideband electronic analogue to digital conversion (ADC) systems have critical problems encountered in high-frequency broadband communication systems that the recent electronic ADCs (EADC) have experienced those such as uncertainty of sampling time. In this paper, an all photonic sampling and quantization ADC and photonic digital to analogue conversion system with six effective number of bits (ENOB) is designed. By using this photonic ADC (PADC), a novel digital radio over fibre link for wireless radio frequency (RF) signal transportation over 20 Km single mode fibre has been designed whose performance is investigated in this paper. In the digital radio over fibre, the dynamic range is independent of the fibre length

Digital receivers for low-frequency radio telescopes UTR-2, URAN, GURT

This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. Since 1998, digital receivers performing on-the-fly dynamic spectrum calculations or waveform data recording without data loss have been used at the UTR-2 radio telescope, the URAN VLBI system, and the GURT new generation radio telescope. Here we detail these receivers developed for operation in the strong interference environment that prevails in the decameter wavelength range. Data collected with these receivers allowed us to discover numerous radio astronomical objects and phenomena at low frequencies, a summary of which is also presented.Comment: 24 pages, 15 figure

Low power all-digital radio-over-fiber transmission for 28-GHz band using parallel electro-absorption modulators

We present a low-power all-digital radio-over-fiber transmitter for beyond 28-GHz using sigma-delta modulation, a 140mW NRZ driver and parallel electro-absorption modulators. 5.25Gb/s (2.625Gb/s) 64-QAM is transported over 10-km SSMF at 1560nm with 7.6% (5.2%) EVM

Digital radio switchover: the UK experience

The UK remains one of the world’s leading countries in the development of digital radio. However, it is unclear when radio will migrate from analogue to digital broadcasting in a similar way to television, which is progressively switching to digital transmission in a number of countries. When digital radio was first emerging, the industry, regulators and policymakers were broadly united in promoting digital radio as the natural successor to analogue. Yet other groups, such as small broadcasters and a number of consumer groups, expressed doubt that digital radio would, or should, replace analogue. The ensuing years have seen these doubts become more widely expressed, and a switchover in 2015, a deadline anticipated by the UK government, looks uncertain. This paper examines the relationship between industry, policymakers and listeners in the process of developing digital radio as a potential analogue replacement

Digital radio over fibre for future broadband wireless access network solution

Copyright @ 2010 IEEEDigital systems are more flexible and environment-process-tolerant than analogue systems. They are more reliable and robust against cross-talk, interference and channel noises, and are capable of covering higher dynamic range than analogue systems. Wideband electronic analogue to digital conversion (ADC) systems have critical problems encountered in high-frequency broadband communication systems that the recent electronic ADCs (EADC) have experienced those such as uncertainty of sampling time. In this paper, an 80Gigasample/s all photonic sampling and quantization ADC and photonic digital to analogue conversion system with six effective number of bits (ENOB) is designed. By using this Photonic ADC (PADC), a digital radio over fibre link for wireless radio frequency (RF) signal transportation over 50 km single mode fibre has been designed whose performance is investigated in this paper