Grundig manual Features Common to North American Digital Radio Systems, Sound Quality

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DIGITAL RADIO GUIDE

TERRESTRIAL TRANSMISSION SYSTEMS - HD RADIO

stereo signal is digitally demodulated and demultiplexed by the FM receiver to produce a sampled, stereo audio signal.

The base band digital signal is first sent to the modem, where it is processed by the First Adjacent Cancellation system to suppress interference from potential first-adjacent analogue FM signals. The signal is then OFDM demodulated, deframed, and passed to the FEC decoding and deinterleaving function. The resulting bit stream is processed by the codec function to decompress the source-encoded digital audio signal. This digital stereo audio signal is then passed to the blend function.

Figure 4.15: FM hybrid IBOC receiver functional block

Tunable

sampled analogue FM FM

FM

Audio

Stereo

 

LO

 

 

Stereo

 

Blend

 

 

 

 

 

 

Det

 

 

Audio

 

X

BPF

A/D

DDC

FM

 

 

Isolation

 

 

 

 

 

RF Front End

 

10.7 MHz IF

 

FM+DAB

 

 

 

 

 

FAC QPSK/OFDM Deframe Demodulator

DSB

Stereo

Diversity

Delay

Audio

Decoder

FEC Decode

and

De-interleave

4.4.7Features Common to North American Digital Radio Systems

(1)Sound Quality

Sound quality of digital radio systems has improved dramatically in recent years with progressively lower bitrates being shown in various applications as achieving near CD quality. Rates well below 96 kbps are routinely utilized in digital radio systems in operation in North America and meeting with wide customer acceptance.

(2)Multipath Resistance

OFDM based systems are made to be resistant to multipath within a guard interval. In the case of the Eureka system, the guard interval is set to 62 ?s (18.6 km at the speed of light). This means that any echoes coming from up to 18.6 km will be considered as constructive to the signal. This allows the use of on-channel repeaters (that are treated as active echoes).

Note also that some systems, such as the Eureka system, also use unequal error protection and error concealment techniques. This allows for a graceful degradation of the digital signal quality when fading occurs and allows for S/N requirement reductions for the receiver. The Eureka system is especially noted for achieving multipath free reception, but narrower bandwidth systems such as the

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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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