Grundig manual Terrestrial Transmission Systems, DRM Digital Radio Mondiale

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DIGITAL RADIO GUIDE

TERRESTRIAL TRANSMISSION SYSTEMS - DRM

4 Terrestrial Transmission Systems

This section provides a technical overview of the various digital radio systems available for terrestrial application: DRM, DAB, ISDB-TSB, and HD Radio. These systems operate in various frequency bands and offer different attributes and features.

4.1DRM – Digital Radio Mondiale

The DRM system encompasses a high level of flexibility in its design. These are noted in this subsection in the signal flow sequence going from the delivery from a program studio or network control centre to a transmission site and on to reception and decoding in a receiver.

4.1.1Key Features of the System Design for the Markets to be Served by the DRM System

The DRM system is a flexible digital sound broadcasting system for use in the terrestrial broadcasting bands below 30 MHz.

It is important to recognize that the consumer radio receiver of the near future will need to be capable of decoding any or all of several terrestrial transmissions; that is narrow-band digital (for <30 MHz RF), wider band digital (for >30 MHz RF), and analogue for the LF, MF, HF and VHF (including the FM) bands. In addition there is the possibility of satellite delivery reception in the L- and S-bands. The DRM system will be an important component within the receiver. It is unlikely that a consumer radio designed to receive terrestrial transmissions in the near future with a digital capability would exclude the analogue capability.

In the consumer radio receiver, the DRM system will provide the capability to receive digital radio (sound, program related data, other data, and still pictures) in all the broadcasting bands below 30 MHz. It can function in an independent manner, but, as stated above, will more likely be part of a more comprehensive receiver – much like the majority of today’s receivers that include AM and FM analogue reception capability.

The DRM system can be used in either 9 or 10 kHz channels, or multiples of these channel bandwidths. Differences on how much of the total available bit stream for these channels is used for audio, for error protection and correction, and for data transfer depend on the allocated band (LF, MF or HF) and on the intended use (for example, ground wave, short distance sky wave or long distance sky wave, with a data application service or without one). In other words, there are modal trade-offs available so that the system can match the needs of broadcasters worldwide.

As noted in more detail in subsequent parts of this subsection, the DRM system has the following structure. It employs advanced audio coding (AAC), supplemented by spectral band replication (SBR), as the main digital audio encoding. These are parts of the MPEG-4 audio standard. SBR significantly improves perceived audio quality so that the overall audio quality of a DRM signal is similar to that of FM (mono). Orthogonal Frequency Division Multiplexing (OFDM) and Quadrature Amplitude Modulation (QAM) are used for the channel coding and modulation, along with time interleaving and forward error correction (FEC). Pilot reference symbols are injected to permit a receiver to “equalize” the channel by comparing a known stored bit sequence with the corresponding received sequence of these special bits, and adjusting accordingly if there are differences in the received compared to the stored sequence.

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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 Description DAB EurekaSystem Development Principal Advantages and ChallengesChallenges Denmark DAB Development Worldwide asBelgium CanadaSingapore FranceGermany ItalySwitzerland South KoreaSpain SwedenUnited Kingdom Synergies with Other Systems Eureka 147 Main System FeaturesMain System Features Infrastructure RequirementsSynergies 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 interleaverPC Receivers In-Home ReceiversIn-Car Receivers Handheld ReceiversJVC List of manufacturers and their DAB productsTeac Audio encoding system Japans Digital Radio Broadcasting ISDB-TSBOverview MethodsTransmission bandwidths Error correction systemMultiplexing System Transmission channel encoding system Modulation methodHierarchical 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 CharacteristicsMultiple voice broadcasting Overview of ServicesTrial receivers Receivers expectedBroadcasting 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 OverviewAdvanced Application Services AAS Core ServicesMain Program Service MPS Station Information Service SISFM 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 Repeaters Deployment StatusTT&C Continental US Satellites GroundMobile 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 ConclusionsLive Some Important Radio PortalsBeethoven Launch Music on Yahoo Launch.yahoo.comMTV Radio IM TuningRadio VH1 Last FMSHOUTcast 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 Data Capacity Modes of OperationTable A.1 Eureka 147 Transmission Parameters IIINumber 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 DABThird Edition Advanced demodulation technique for CofdmTable A.3 Etsi Standards relating to Eureka Number TitleGSM / Pstn / Isdn / Dect ITU Publications and Recommendations Receiver StandardsTable A.4 Receiver Standards for Eureka Reference TitleNasb Appendix B Relevant World Wide WebsitesBBC DAB 111 Glossary of Acronyms DRP DRBDrdb DRMITU IeeeIfpi ISDB-TSBPNG P2PPAD PDATmcc TDMTdma TMCDisclaimer

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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