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The NAB Convention provides an annual forum for discussion on a wide range of research, legal and policy issues, technology trends and management techniques for and related industries, including the and multi-media. This is the first report by Bob Greeney, ABA Director, Technology on the major issues reported at the meetings of the NAB'99 Convention held from 17- 22 April 1999, in Las Vegas. His second report will be in July ABA Update.

Broadcasting technology developments

Th e Na t ional Association Digital Three US companies described mented in many European countries as well as of Broadcasters (NAB) is p rogress with their proposed In-Band-on-Chan­ Ca nada, China, Singapore and other countries. the US broadcasting nel (IBOC) FM systems. All IBOC Canada has legislation supporting Eureka- 147 industry forum which, as systems claim to achieve 'near CD q uali ty' sound and is well advanced in implementing its digital well as being the ind ustry w ith a data rate of about 128 kil obits per second. in the new L-Band (1500 MHz). forum for exchan ge of • Lucent Technologies: proposes a proprietary Eureka-147 services are now avail able in Mon­ ideas, advises t he US coding system called Perceptual Audio Coding treal, Ottawa, Toronto and Vancouver. Mexico Government o n iss ues of to provide a 96 kbps data stream. Lu cent is has decided that Eureka-147 is suitable for the ir importance to the confident that they have developed the best purposes and intends to start implementation in broadcasti ng indust ry in system fo r IBOC digital radio system. 1999, also in the L-Band. (Mexico assisted Britain the USA. • USA Digital Radio: uses a multi carri e r modula­ with th e satellite transmissio ns of Eur ka-147 in tion (MCM) technique similar to the OFDM 1996, just after Australia conducted the first NAB al so sponso rs an system used by Eureka-147 (the European digital satellite trials of the system). Mexico has also said equipment exposition radio syste m). USADR indicated that the ir system that their administration has not closed the door during the convention. is in test and should be p roven by the end of o n any of the FM IBOC systems. Mexico believes Thi s year the emphasis on 1999. that if IBOC becomes successfu l, it can be production to • Digital Radio Express: also uses a multi carrier introduced in the FM bands as well as operating t ransmission equipment system and cl aims to be ready for Eureka-1 47 digital rad io services in the L-Band. for digital televisi on and selection as the IBOC system o f choice by Digital Radio Mondiale. DRM is a consortium radio services and broadcaste rs by the end of 1999. of 40 companies from Europe, the USA and interactive multi-media The Fede ral Communications Commission's Japan that is developing a digital radio system to services . National Radio Standards Committee (NRSC) replace AM radio. met at NAB'99 and determined that the three The DRM system delivers a robust digital and IBOC proponents are to p rovide tests results, by better quality sound replacing short-wave and 15 December 1999, that show that their pro­ long-wave overseas AM broadcasting services. It posed IBOC systems gives better sound quality is a p roven, re liable system that operates satis­ than the AM and FM services. The NRSC expects factorily within a 10 kHz w ith a data to complete assessment of the IBOC test results rate up to 19 kbps. Because of its limited by Ma rch 2000. Beyond 1999, it is not clear bandw idth and lower data rate, compared to whether or how the FCC will choose one of a other digital technologies, DRM does not claim combin atio n of the p roposed IBOC systems to to deli ver CD quality sound. provide the USA with a single di gital ra dio Unlike the p roposed FM IBOC systems, the standard for adoption by broadcasters. The con­ DRM is a conversion technology, requi ring a cern is that, unless a single standard is agreed, vacant AM channel for its implementation. There­ digital in the USA may strug­ fore the DRM technology cannot be fu lly ex­ gle to survive in the same way that AM stereo ploited until existing AM analog services are fa ltered, because broadcasters and consumers switched off. It appears to have application in were confused by the mu ltiplicity of simi la r but Australia as AM broadcasters look to digital incompatible standards. broadcasting fo r their future. Eureka-147: This d igital rad io system provides • Integrated Services -­ data rates of around 256 kbps per service and Terrestrial. Japan has announced its own devel- C> delivers CD quality sound. It is being imple- opments in digital radio broadcasting. The ISDB-

JUNE 1999 17 ABA~Update D! .. i:. .~ . ~ ..': ..~ .. ~ . ~ ..? .. ?. . ~•...... •...... T proposal uses part of the band segmented has launched one sate llite, AfriSpace, whi ch modulati on system to p rovide a passed acceptance tests on 14 April 1999 and rugged and reliable digital radio service for commercial service w ill begin soon. It uses portable and mobile receivers. This ISDB system single carrier modulation with a maximum data is similar in many aspects to both the European rate of around 1. 6 Mbps. Intended as a replace­ DVB-T digital television and the Eureka-1 47 ment for short-wave services, it provides reliable COFDM digital radio systems and provides fl ex­ high-speed interacti ve multi-media services to ibility in data rate according to requirements of areas not adequately served by other media. the broadcasters. The narrow band ISDB-T dig­ • XM is a US development w hich ital radio system is expected to receive approval provides direct-to-home satellite radio services in Japan later this year, for domestic implementa­ for subscription broadcasters. XM radio is deliv­ tion. ered as part of a bouquet of services including FCC develop ments During his keynote speech, digital television services but its radio services FCC Chairman William Ke nnard made many are aimed at niche markets. references to future use of the spectrum and how • CD Radio is another US satellite digital radio it can be auctioned to the user who valu es service using multi carrier modulation to provide particul ar spectrum the most. subscriber radio services by satellite, operating Of particular significance to IBOC develop­ now. ments are proposals for low power FM radio and multi-media Discussions on serv ices, known in the USA as microstations. datacasting and multi-media broadcasting at­ These LPFM services w ill operate in the spaces tracted a number of high profile speakers from between existing high powe r FM broadcasting Microsoft , WebTV, Sun Micro-systems, and Larry services at powers of 10 watts, 100 watts and up Ellison of Oracle Systems. Broadcasters and to 1000 watts. O nce these services are estab­ content p roviders consider that multi-media serv­ lished it will be much more difficult for FM IBOC ices are the major new business opportunities: systems to operate in the FM band w ithout many want to provide inte ractive multi-m cl ia causing interference to the LP FM services. services. Two datacasting models are: Digital satellite radio: Two new digital satellite • carousel m odel: broadcasters transmit the same radio systems were unveil ed at NAB'99. Japan is material on a cyclic basis and viewers receive developing a satellite digital broadcasting serv­ and store the data as it is transmitted for later ice for do mestic use, operating at 2.6 GHz . It is recovery and viewing; and intended to provide reliable service in the pres­ • continuous transmission m odel: (or streaming ence of multipath reflections-in circumstances media data transmissio ns) data is continuall y where FM suffe rs from severely impaired recep­ transmitted and can be received by any author­ tion. Still in development, the system is expected ised user for recording or immediate use. to be approved in Japan by the end of 1999. It In each case, interactive capability is a critical provides for satellite delivery and for gap fill er fa ctor. The return path is either a te lephone line terrestrial in the 2.6 GHz band (S­ or a GSM digital te lephone implying that the band). return data rate need not be great, typically of the The service uses different frequencies within order of 14 kbps or less for GSM , or 56 kbps the band, for wide-area and small-area transmit­ using a telephone line . The forward delivery ters, to ensure reception by all domestic receiv­ capacity of data and multi-media services is seen ers within the service area. Wide area gap fill er as the major issue, requiring a minimum of transmitters receive their signals from the satel­ around 300 kbps (compared with the Internet lite at Ku band (12 GHz) and retransmit them in over the telephone currently providing 56 kbps). the 2.6 GHz band (overcoming inte rference One speaker indicated that he sees each digital problems w ithin the coverage area), while small television receiver becoming a home server for area terrestrial retransmission re-use the same HDTV with 10 Gbit hard drives to become avail­ 2.6 GHz freque ncies received from the satellite able next year, becoming a multi-media home to provide localised extensio n of coverage in platform (as described in the DVB standards adopted small pockets of poor reception for the 2.6 GHz for Australian digital television). According to a satellite signals due to shadowing by buildings. speaker from Japan indicated that storage devices Three satellite digital radio services companies for HDTV will need about 46 Mbps data handling also reported : capacity for replay while recording (the advent of a • WorldSpace proposes to use three satellites to digital VCR). We will need new disk storage cover remote and regional parts of the world, technology to handle the very high data rates required serving Africa, Asia and the Ame ri cas. To elate it for storage and simultaneous repl:;iy of HDTV. ~

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