Grundig Digital Radio manual Satellite Transmission, WorldSpace ITU-R System D, Broad Picture

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DIGITAL RADIO GUIDE

SATELLITE TRANSMISSION - WORLDSPACE

5 Satellite Transmission

The Broad Picture

For many years, satellites in geostationary orbits (GSO’s) have been used successfully by broadcasters for distributing programmes and services from the originating studios to terrestrial transmitting stations. It is cost effective and reliably delivers high quality signals to each transmitting station. This method of distribution is of particular benefit to international broadcasters that in the past relied on SSB and DSB short-wave signals for feeds to remote relay stations.

Today, radio broadcast services can be included in the bandwidth used for an FM satellite television signal, or as part of a bundle of digital channels as used in Astra Digital Radio. In all cases, satellite tuners are needed to receive these broadcasts, which are usually transmitted in the Ku Band.

Direct radio broadcasts from geostationary satellites to fixed receivers with externally mounted line-of-sight antennas is routine and presents no problems. It is a much more demanding requirement to reach receivers that are mobile or portable, but the majority of radio listeners have radio receivers of this type. Any radio transmission system, terrestrial or satellite, which fails to deliver a satisfactory service to such receivers will probably not find widespread acceptance.

The main difficulty in providing a satellite broadcast to an audience on the move is occasional blockage by buildings etc. This can reduce the signal by 10 to 20 dB, which it is impractical to compensate for with an increased link margin.

5.1WorldSpace – ITU-R System D

WorldSpace is a commercial organisation based in Washington D.C. with world-wide interests. It has planned for three geo-stationary satellites, named AfriStar, AsiaStar and AmeriStar to provide global coverage. They will have L-Band payloads and each satellite covers its designated target area with three “spot” beams. Each beam has two transponders (one transparent and one with on-board processing). The aim is to provide digital radio and ancillary services to audiences in the footprints of these satellites using ITU-R Digital System D. As the names imply, the continental zones to be served by these satellites are Africa, Asia and Central and South America. See Figure 5.1.

The primary aim of the original WorldSpace concept is to provide a simple radio service, but as the project has developed, there is now more emphasis on mobile and multimedia features involving data and image transmission. Trials of MPEG-4 video have been successfully completed recently.

The WorldSpace project is innovative and has a number of points in its favour. These include the size of the coverage areas in relation to the cost of the satellites, advanced low bit-rate audio coding and straight forward satellite uplinking arrangements. An enhanced service using terrestrial repeaters for reliable mobile reception is has been successfully trialled and is being planned for introduction soon.

The approximate target regions for the transmissions from each satellite in the WorldSpace system are shown in Figure 5.2. AfriSpace commenced operation in 1999 and AsiaSpace in 2000. AmeriSpace has not been launched. Consideration is also being given to planning an additional satellite for providing service for Europe.

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Contents Page Page Foreword Page Table of Contents Appendix C Glossary of Acronyms Introduction What is Digital Radio? DRM+ Terrestrial in service date Satellite Service dateDigital Radio Systems Why Digital Radio? DRM Digital Radio Mondiale Terrestrial Transmission SystemsOverall design Brief Description of the DRM SystemDistribution Interface DRM Source Encoding and Decoding Audio Source CodingDRM Source Decoding Channel coding and modulation Over the air Transmitter Considerations4 DRM+ System Development DAB EurekaPrincipal Advantages and Challenges System DescriptionChallenges Belgium DAB Development Worldwide asCanada DenmarkGermany FranceItaly SingaporeSpain South KoreaSweden SwitzerlandUnited Kingdom Main System Features Eureka 147 Main System FeaturesInfrastructure Requirements Synergies with Other SystemsSynergies with Digital Radio Mondiale DRM DAB-Based Multimedia Broadcast Systems DMB T-DMB Future Developments of DABSynergies with Digital Television German DXB Project IP over Enhanced Packet ModeDAB-IP Enhanced Audio Codec, DAB+ DAB as carrier of multichannel audioDigital Radio Guide Terrestrial Transmission Systems DAB Types of Receivers Conceptual diagram of the outer coder and interleaverIn-Car Receivers In-Home ReceiversHandheld Receivers PC ReceiversJVC List of manufacturers and their DAB productsTeac Overview Japans Digital Radio Broadcasting ISDB-TSBMethods Audio encoding systemMultiplexing System Error correction systemTransmission channel encoding system Modulation method Transmission bandwidthsHierarchical transmission and partial reception Data Segment SpectraPage Parameter restrictions in connected transmission Example of connected transmission three TS’sInformation bit rates for the triple-segment transmission*5 Transmission capacitiesReceivers CharacteristicsTrial receivers Overview of ServicesReceivers expected Multiple voice broadcastingBroadcasting of simplified moving images Download service experimentOutlook for the Future IBiquity HD Radio System HD Radio AM and FM Receivers HD Radio Standards ActivityTypical HD Radio Automobile Receivers HD Radio System Technical Design OverviewMain Program Service MPS Core ServicesStation Information Service SIS Advanced Application Services AASFM Extended Hybrid Waveform Waveforms and SpectraHybrid Waveform FM All Digital Waveform 12 Hybrid AM HD Radio system spectrum allotment HD Radio Subsystems13 Functional Block Diagram of HD Radio System RF/Transmission System Receiver SystemsMultipath Resistance Features Common to North American Digital Radio SystemsSound Quality Audio Quality Ratings Frequency ResponseMpeg AAC Infrastructure Requirements Licensees Deployment StatusCase Study Allocations in Region Issues related to Terrestrial SystemsSpectrum Availability DAB DVB-T 18 RRC-06 planning area19 T-DAB coverages in Band Entries HD Radio Iboc Implications of SimulcastingDRM Digital Radio Mondiale CoverageDigital Radio Guide Terrestrial Transmission Systems Issues Broad Picture Satellite TransmissionWorldSpace ITU-R System D WorldSpace Coverage Map Transmission Footprints WorldSpace Up-link Coverage JVC Sirius Satellite Radio / XM Satellite Radio Sirius Overview Sirius Sdars Delivery System Raan Sirius ConstellationSirius Ground Track TT&C Deployment StatusContinental US Satellites Ground RepeatersMobile Broadcasting Corp. and TU Media Corp. ITU-R System E Bringing Radio to the Internet Internet Radio IRIntroduction Internet Radio peculiarities Internet Radio as a complement to established radio services Internet-only stations IR Portals and Music Portals Streaming technology for radio servicesDistribution networks Server-clientP2P networks WiMAX MulticastingPodcasting Internet Radio terminals and playback devicesInternet Radios relation with the traditional radio Measuring audience Digital Radio Guide Internet Radio Virgin Radio Case studies10.1 VRT Swedish Radio multichannel audio distribution Summary and ConclusionsBeethoven Some Important Radio PortalsLaunch Music on Yahoo Launch.yahoo.com LiveRadio VH1 IM TuningLast FM MTV RadioSHOUTcast Some Sources for the Digital Radio Guide Etsi Cenelec IEC Digital Radio Guide Sources Overview Major System FeaturesAppendix a The Eureka 147 System System Description Table A.1 Eureka 147 Transmission Parameters Modes of OperationIII Data CapacityNumber of audio services in a multiplex Data ServicesAudio Quality Spectrum Issues Eureka 147 Channel PlansTable A.2 Example of possible number of programs ITU DSB Handbook Planning ParametersBand 1452-1492 MHz Propagation PropertiesVHF Band Multimedia Object Transport MOT Recent system developmentsDynamic Label Electronic Programme Guide EPG Broadcast WebsiteSlide Show Etsi DAB Virtual Machine DAB JavaDAB Receiver Interfaces Conditional AccessTopNews SBR LayerFile caching in the receiver Tpeg transport in DAB IP datacasting in DABTable A.3 Etsi Standards relating to Eureka Advanced demodulation technique for CofdmNumber Title Third EditionGSM / Pstn / Isdn / Dect Table A.4 Receiver Standards for Eureka Receiver StandardsReference Title ITU Publications and RecommendationsNasb Appendix B Relevant World Wide WebsitesBBC DAB 111 Glossary of Acronyms Drdb DRBDRM DRPIfpi IeeeISDB-TSB ITUPAD P2PPDA PNGTdma TDMTMC TmccDisclaimer

Digital Radio specifications

The Grundig Digital Radio represents a significant advancement in radio technology, combining aesthetics, functionality, and a user-friendly interface. As a pioneer in the audio and electronics industry, Grundig has successfully integrated modern digital capabilities into its traditional radio design, appealing to both nostalgic listeners and tech-savvy users.

One of the standout features of the Grundig Digital Radio is its versatility in reception. With DAB+ (Digital Audio Broadcasting) technology, users can enjoy a wide array of radio stations with superior sound quality, free from the hiss and interference commonly associated with analog broadcasts. The inclusion of FM and AM bands ensures that listeners are not limited, providing access to local stations that may not yet have transitioned to digital.

The Grundig Digital Radio is designed with ease of use in mind. Its intuitive interface, often featuring a clear LCD display, allows users to navigate through stations and settings effortlessly. Many models also include a built-in tuner that automatically scans and presets available stations, simplifying the setup process. For those who appreciate personalization, some variants come equipped with customizable presets, allowing users to save their favorite stations for quick access.

Portability is another key characteristic of the Grundig Digital Radio. Many models are lightweight and come with built-in handles, making them ideal for on-the-go listening, whether it's in the garden, on the beach, or during a picnic. Battery options, alongside mains power, ensure that users can take advantage of their radios wherever they choose.

In terms of sound quality, Grundig utilizes advanced audio technologies to deliver rich and clear sound. Enhanced bass responses and treble controls allow users to fine-tune their listening experience to match their preferences. Furthermore, many models feature additional inputs, such as AUX and USB ports, enabling users to connect their smartphones or other devices, expanding their audio options.

Other notable characteristics include built-in alarms and timers, which make the Grundig Digital Radio a versatile companion for daily routines. Some models even support Bluetooth connectivity, allowing for seamless streaming from a variety of devices.

In summary, the Grundig Digital Radio embodies the perfect blend of traditional radio appeal and modern digital technology, offering versatility, ease of use, superior sound quality, and portability to meet the diverse needs of today’s listeners. Its well-thought-out features and user-friendly design make it an excellent choice for anyone looking to enhance their audio experience.
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