DIGITAL RADIO GUIDE

TERRESTRIAL TRANSMISSION SYSTEMS - HD RADIO

HD Radio system have also been shown to be multipath-free even in challenging propagation conditions.

(3)Frequency Response

It is difficult to evaluate the exact frequency response of a codec, because it will change dynamically depending on the available bit rate and the difficulty of encoding the instantaneous audio material. A quick example can be demonstrated using a single carrier frequency sweep on any codecs. Typically total frequency response of 20 kHz is measured in such tests, even at 16 kbps. On the other hand, encoding a rich stereo program on the same codec at 16 kbps, may result in a pure monophonic signal of less than 5 kHz.

Consequently, the codec has to be tailored to the program content being broadcast. See Table 4.5 for MPEG Layer II implementation recommendations.

Table 4.5: Recommended MPEG II data and sampling rates

for various program material

Voice program:

48 kbps . 24 KHz Sampling rate / Mono

Mono program with music:

80 kbps / 48 KHz Sampling rate / Mono

Oldies music:

112 kbps / 48 KHz / Joint Stereo

(4)Audio Quality Ratings

The basic audio quality is defined by the codec used and the ruggedness of the transmission channel. The performance quality of different codecs when critical material is encoded has been measured as shown in Figure 4.16.

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Grundig Digital Radio manual Frequency Response, Audio Quality Ratings

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.