DIGITAL RADIO GUIDE

APPENDIX A: EUREKA 147

Modes of Operation

Eureka 147 provides four transmission mode options that allow for a wide range of transmission frequencies, between 30 and 3000 MHz, and network configurations. For the nominal frequency ranges, the transmission modes have been designed to provide good mobile reception by overcoming multipath echoes, which occur when the signal bounces off buildings and other objects and receivers must deal with multiple and slightly out of phase versions of the same signal.

Mode I is most suitable for a terrestrial SFN in the VHF range, because it allows the greatest distances between transmitters. Mode II is most suitable for hybrid satellite/terrestrial transmission up to 1.5 GHz and local radio applications that require one terrestrial transmitter. Mode II can also be used for a medium to large scale SFNs in the L Band by inserting, if necessary, artificial delays at the transmitters and/or by using directive transmitting antennas. Mode III is most appropriate for cable, satellite and complementary terrestrial transmission, since it can be operated at all frequencies up to 3 GHz for mobile reception and has the greatest phase noise tolerance. Mode IV is most suitable for medium to large scale SFNs in the L Band while still accommodating mobile reception at reasonable highway speeds (up to approximately 120 km/h). However, it is less resistant to degradation at higher vehicle speeds than this.

Table A.1: Eureka 147 Transmission Parameters

System Parameter

 

Transmission Mode

 

 

 

 

 

 

 

I

II

III

IV

 

 

 

 

 

No. of radiated carriers

1536

384

192

768

 

 

 

 

 

Nominal Maximum transmitter

96 km

24 km

12 km

48 km

separation for SFN

 

 

 

 

 

 

 

 

 

Nominal frequency range for mobile

375 MHz

1.5 GHz

3 GHz

1.5 GHz

reception

 

 

 

 

 

 

 

 

 

Speed/Coverage trade off

No

No

No

Yes

Frame Duration

96 ms

24 ms

24 ms

48 ms

 

 

 

 

 

Total Symbol Duration

1246 s

312 s

156 s

623 s

 

 

 

 

 

Useful Symbol Duration

1000 s

250 s

125 s

500 s

Guard Interval Duration

246 s

62 s

31 s

123 s

 

 

 

 

 

Null Symbol Duration

1297 s

324 s

168 s

648 s

Data Capacity

Audio and data services are carried in the main service channel (MSC) of the Eureka 147 multiplex. This channel supports a gross data rate of 2.304 MBps. However, the net data rate (e.g., the actual capacity available for use) depends on the protection level applied to services. For audio only services the net capacity of the ensemble varies between 783 (highest protection) and 1728 kbps (lowest protection). The corresponding range for data only services is 576 and 1728 kbps. At a median protection level the available net capacity for both audio and data services is 1.152 MBps.

Within the MSC each audio or data service is carried in a subchannel. Up to 63 subchannels can be supported, each of which is treated individually as far as error protection is concerned.

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Grundig Digital Radio manual Modes of Operation, Table A.1 Eureka 147 Transmission Parameters, Iii, Data Capacity

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.