DIGITAL RADIO GUIDE

APPENDIX A: EUREKA 147

contents regularly. There is no need for return link to the service provider. This "audio anytime" system is particularly attractive for in-car applications.

IP datacasting in DAB

The DAB system is capable of carrying IP packets (datagrams) using IP/UDP protocol.27 As these packets travel unidirectionally from a service provider to many users simultaneously, this is a form of IP Multicasting, e.g., pushing the same contents to several users concurrently. The IP datagrams are tunnelled through a DAB packet mode service component (SC). This is done by encapsulating the IP datagram in an MSC data group on packet mode transport level. It is not necessary to establish a connection between the transmitter and the user prior to the transmission of data.

For connection oriented point-to-point transport, TCP has to be used (rather than UDP). TCP requires an interaction channel for the return flow of acknowledgements.

Further work is necessary to be carried out similar to that performed by the DVB-IPI project in order to specify the discovery and selection of the data services by the user.

The Digital Video Broadcasting (DVB) Project has developed a data broadcasting standard describing an IPv4 and IPv6 datagrams encapsulation in MPEG-2 transport stream. This system is commonly called Multi-Protocol Encapsulation (MPE) or Data Piping28 and includes dynamic address resolution, multicast group membership and other supporting procedures and protocols. The overhead due to encapsulation is reasonably low, e.g., below 3%.

IP datacasting is an interesting option for the DAB systems required to work with IP-enabled devices such as mobile phones and PDAs. The IP layer could be used as a common communications layer between the two systems. IP datacasting over DAB will bring the data content such as moving pictures, audio, web pages, computer programmes and software upgrades reliably to each user (or a group of users) and will thus expand significantly market opportunities of DAB. IP datacasting will pave the way towards the personalisation of broadcast services.

TPEG transport in DAB

It is well known to all broadcasters that radio is an ideal (and the cheapest) medium to inform travellers about the road conditions and traffic jams – provided that such information is timely and relevant, in the correct location. Currently analogue FM radio uses a well-established RDS-TMC (Traffic Message System) system. However, the TMC is essentially limited to inter-urban road events and every decoder must have a location database to interpret any message received.

TPEG was developed by the EBU to overcome these limitations. TPEG delivers very rich location referencing information with every message, so that receivers do not need a location database. Thus, navigation systems which are now becoming a standard commodity in the car can "machine read" the location content and localise an event directly onto the map display. A text- only device (such as a PDA) is able to present locally found names such as a railway station name and a platform number directly to an end user as a text message. Such a message can be rendered in the language of choice of the end user. TPEG can filter the information to avoid receiver overload, so that end users can select massages on any number of criteria, such as the type of location, mode of public transport, direction of travel, event, etc.

27ES 201 735 V1.1.1 Digital Audio Broadcasting (DAB); Internet Protocol (IP) Datagram Tunnelling

28EN 301 192 V1.3.1 (2003-05) Digital Video Broadcasting (DVB); DVB specification for data broadcasting

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Grundig Digital Radio manual IP datacasting in DAB, Tpeg transport in DAB

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.