Grundig Digital Radio manual Server-client, Distribution networks

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DIGITAL RADIO GUIDE

INTERNET RADIO

The streaming system architecture comprises four elements: capture and encoding, serving, distribution and delivery and media player.

Capture and encoding takes the source audio from the microphone and exports it into a compressed (encoded) computer file. These files are stored on a content server which controls the real-time delivery of the stream. The distribution channel (usually the Internet) connects the server to the player. The media player renders the media on the PC or another device (hand-held wireless devices, games consoles, interactive TV, etc).

As Internet is overlaid on telecommunications infrastructure, IR is now widely available via a variety of two-way communication networks, both wired and wireless. narrow-band (dial-up) at home and broadband connections in offices, via WLAN hot spots in airports, congress centres and other public places. The number of listening hours is staggering.

Broadband access is obviously a big plus and some of the streams are so good you can enjoy them over your home stereo system.

IR services can be delivered in a variety of configurations ranging from direct server- client to podcasting.

(1)Server-client

Unicasting is a classical approach to radio streaming. Requests from clients (users) to receive a stream are managed by a server or a cluster of servers. In case of clustering, load balancing is used to improve reliability of the stream delivery, especially if one of the servers breaks down. The server cluster feeds a common Internet line used to transmit the streams to the clients. The total bandwidth provided by such a server farm is proportional to the number of clients and the bitrate of streams. This means that doubling the number of clients or bitrate will double the system capacity and cost.

Unicasting also has a "scaling" problem. Since all the streams are transmitted to the Internet from one source, a server quickly reaches its upper capacity limit, resulting in a "server busy" message.

(2)Distribution networks

The Content Delivery Network (CDN) consists of a large number (typically several thousand) of "edge"14 servers situated around the world. Each server uses the same home page and is uploaded with the same content. The user gets content from the nearest server, so that the access delay is minimal. The CDN approach distributes the load among the geographically separated servers and increases the possible number of concurrent requests and streams that may be handled. The CDNs can potentially cater to several thousand simultaneous streams but are very costly. For example, Akamai's globally distributed edge computing platform comprises more than 15,000 servers in more than 1,100 networks in 70 countries.

14The word "edge" is used here to mean "close to the user".

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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? 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 DAB-Based Multimedia Broadcast Systems DMB T-DMB Future Developments of DABSynergies with Digital Television German DXB Project IP over Enhanced Packet ModeDAB-IP 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 broadcastingBroadcasting of simplified moving images Download service experimentOutlook for the Future 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 AASFM Extended Hybrid Waveform Waveforms and SpectraHybrid 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 SystemMultipath Resistance Features Common to North American Digital Radio SystemsSound Quality Frequency Response Audio Quality RatingsMpeg AAC Infrastructure Requirements Deployment Status LicenseesCase Study Allocations in Region Issues related to Terrestrial SystemsSpectrum Availability 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 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 Sirius Constellation RaanSirius Ground Track Deployment Status TT&CContinental 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 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 Virgin Radio Case studies10.1 VRT 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 Overview Major System FeaturesAppendix a The Eureka 147 System System Description Modes of Operation Table A.1 Eureka 147 Transmission ParametersIII Data CapacityData Services Number of audio services in a multiplexAudio Quality Spectrum Issues Eureka 147 Channel PlansTable A.2 Example of possible number of programs Planning Parameters ITU DSB HandbookBand 1452-1492 MHz Propagation PropertiesVHF Band Recent system developments Multimedia Object Transport MOTDynamic Label Electronic Programme Guide EPG Broadcast WebsiteSlide Show DAB Virtual Machine DAB Java EtsiConditional Access DAB Receiver InterfacesTopNews SBR LayerFile caching in the receiver 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 RecommendationsNasb Appendix B Relevant World Wide WebsitesBBC DAB 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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