Grundig Digital Radio manual Channel coding and modulation

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DIGITAL RADIO GUIDE

TERRESTRIAL TRANSMISSION SYSTEMS - DRM

FAC provides information on the signal bandwidth and other such parameters, and is also used to allow service selection information for fast scanning. The SDC gives information to a receiver on how to decode the MSC, how to find alternative sources of the same data, and gives attributes to the services within the multiplex.

The MSC multiplex may contain up to 4 services, any one of which can be audio or data. The gross bit rate of the MSC is dependent on the channel bandwidth and transmission mode being used. In all cases, it is divided into 400 millisecond frames.

The FAC’s structure is also built within a 400 millisecond frame, and is designed without interleaving, for example, to ensure rapid delivery of the information it contains. The design without interleaving is also to ensure fastest decoding of basic data by the Rx before it can do the audio decoding. The channel parameters are included in every FAC frame segment. The service parameters are carried in successive frames, one service per frame. The names of the FAC channel parameters are: base/enhancement flag, identity, spectrum occupancy, interleaver depth flag, modulation mode, number of services, reconfiguration index, and reserved for future use. These use a total of 20 bits. The service parameters within the FAC are: service identifier, short identifier, conditional access, language, audio/data flag, and reserved for future use. These use a total of 44 bits.

The SDC’s frame periodicity is 1200 milliseconds. The fields of information are: multiplex description, label, conditional access, frequency information, frequency schedule information, application information, announcement support and switching, coverage region identification, time and date information, audio information, FAC copy information, and linkage data. As well as conveying these data, the fact that the SDC is inserted periodically into the waveform is exploited to enable seamless switching between alternative frequencies.

(5)Channel coding and modulation

The coding/modulation scheme used is a variety of coded orthogonal frequency division multiplexing (COFDM), which combines the OFDM with the Multi-Level Coding (MLC) based upon convolutional coding. The convolutional coding provides a level of error protection. These two main components are supplemented by time interleaving (“scrambling” of the bit stream) and the provision of pilot (predetermined value) cells for instantaneous channel estimation. All of this mitigates the effects of short-term signal fading, whether selective or flat.

Taken together, this combination provides excellent transmission and signal protection possibilities in the narrow 9 or 10 kHz channels in the LF, MF and HF broadcasting frequency bands. It can also be used for “multi-channel” DRM use; that is 18 or 20 kHz channels, using 2 contiguous ITU-R channels. This level of bandwidth will permit good stereo broadcasting.

For OFDM, the transmitted signal is composed of a succession of symbols, each including a “guard interval,” which is a cyclic time prefix that provides a “dead time” to counter intersymbol interference due to multipath delay spread. Orthogonality refers to the fact that, in the case of the design of the DRM system, each symbol contains around between 100 and 200 subcarriers spaced evenly across the 9 or 10 kHz channel in such a way that their signals do not interfere with each other (are orthogonal). The precise number of subcarriers, and other parameter considerations, are a function of the actual letter modes used: ground wave, sky wave, and highly robust transmissions.

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Contents Page Page Foreword Page Table of Contents Appendix C Glossary of Acronyms Introduction What is Digital Radio? Digital Radio Systems Terrestrial in service date Satellite Service dateDRM+ Why Digital Radio? Terrestrial Transmission Systems DRM Digital Radio MondialeBrief Description of the DRM System Overall designDistribution Interface Audio Source Coding DRM Source Encoding and DecodingDRM Source Decoding Channel coding and modulation Transmitter Considerations Over the air4 DRM+ DAB Eureka System DevelopmentPrincipal Advantages and Challenges System DescriptionChallenges DAB Development Worldwide as BelgiumCanada DenmarkFrance GermanyItaly SingaporeSouth Korea SpainSweden SwitzerlandUnited Kingdom Eureka 147 Main System Features Main System FeaturesInfrastructure Requirements Synergies with Other SystemsSynergies with Digital Radio Mondiale DRM Synergies with Digital Television Future Developments of DABDAB-Based Multimedia Broadcast Systems DMB T-DMB DAB-IP IP over Enhanced Packet ModeGerman DXB Project DAB as carrier of multichannel audio Enhanced Audio Codec, DAB+Digital Radio Guide Terrestrial Transmission Systems DAB Conceptual diagram of the outer coder and interleaver Types of ReceiversIn-Home Receivers In-Car ReceiversHandheld Receivers PC ReceiversList of manufacturers and their DAB products JVCTeac Japans Digital Radio Broadcasting ISDB-TSB OverviewMethods Audio encoding systemError correction system Multiplexing SystemTransmission channel encoding system Modulation method Transmission bandwidthsData Segment Spectra Hierarchical transmission and partial receptionPage Example of connected transmission three TS’s Parameter restrictions in connected transmissionTransmission capacities Information bit rates for the triple-segment transmission*5Characteristics ReceiversOverview of Services Trial receiversReceivers expected Multiple voice broadcastingOutlook for the Future Download service experimentBroadcasting of simplified moving images IBiquity HD Radio System HD Radio Standards Activity HD Radio AM and FM ReceiversHD Radio System Technical Design Overview Typical HD Radio Automobile ReceiversCore Services Main Program Service MPSStation Information Service SIS Advanced Application Services AASHybrid Waveform Waveforms and SpectraFM Extended Hybrid Waveform FM All Digital Waveform HD Radio Subsystems 12 Hybrid AM HD Radio system spectrum allotment13 Functional Block Diagram of HD Radio System Receiver Systems RF/Transmission SystemSound Quality Features Common to North American Digital Radio SystemsMultipath Resistance Frequency Response Audio Quality RatingsMpeg AAC Infrastructure Requirements Deployment Status LicenseesSpectrum Availability Issues related to Terrestrial SystemsCase Study Allocations in Region 18 RRC-06 planning area DAB DVB-T19 T-DAB coverages in Band Entries Implications of Simulcasting HD Radio IbocCoverage DRM Digital Radio MondialeDigital Radio Guide Terrestrial Transmission Systems Issues WorldSpace ITU-R System D Satellite TransmissionBroad Picture WorldSpace Coverage Map Transmission Footprints WorldSpace Up-link Coverage JVC Sirius Satellite Radio / XM Satellite Radio Sirius Overview Sirius Sdars Delivery System Sirius Constellation RaanSirius Ground Track Deployment Status TT&CContinental US Satellites Ground RepeatersMobile Broadcasting Corp. and TU Media Corp. ITU-R System E Introduction Internet Radio IRBringing Radio to the Internet Internet Radio peculiarities Internet Radio as a complement to established radio services Streaming technology for radio services Internet-only stations IR Portals and Music PortalsServer-client Distribution networksWiMAX Multicasting P2P networksInternet Radio terminals and playback devices PodcastingInternet Radios relation with the traditional radio Measuring audience Digital Radio Guide Internet Radio 10.1 VRT Case studiesVirgin Radio Summary and Conclusions Swedish Radio multichannel audio distributionSome Important Radio Portals BeethovenLaunch Music on Yahoo Launch.yahoo.com LiveIM Tuning Radio VH1Last FM MTV RadioSHOUTcast Some Sources for the Digital Radio Guide Etsi Cenelec IEC Digital Radio Guide Sources Appendix a The Eureka 147 System System Description Major System FeaturesOverview Modes of Operation Table A.1 Eureka 147 Transmission ParametersIII Data CapacityData Services Number of audio services in a multiplexTable A.2 Example of possible number of programs Spectrum Issues Eureka 147 Channel PlansAudio Quality Planning Parameters ITU DSB HandbookVHF Band Propagation PropertiesBand 1452-1492 MHz Recent system developments Multimedia Object Transport MOTDynamic Label Slide Show Broadcast WebsiteElectronic Programme Guide EPG DAB Virtual Machine DAB Java EtsiConditional Access DAB Receiver InterfacesFile caching in the receiver SBR LayerTopNews IP datacasting in DAB Tpeg transport in DABAdvanced demodulation technique for Cofdm Table A.3 Etsi Standards relating to EurekaNumber Title Third EditionGSM / Pstn / Isdn / Dect Receiver Standards Table A.4 Receiver Standards for EurekaReference Title ITU Publications and RecommendationsBBC DAB Appendix B Relevant World Wide WebsitesNasb 111 Glossary of Acronyms DRB DrdbDRM DRPIeee IfpiISDB-TSB ITUP2P PADPDA PNGTDM TdmaTMC 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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