Grundig Digital Radio User Manual
DIGITAL RADIO GUIDE
TERRESTRIAL TRANSMISSION SYSTEMS - ISSUES
62
Figure 4.21: End of the transition period
In summary, the full potential of the new digital plans will not be available until the
analogue switch off.
analogue switch off.
In terms of propagation performance at L-Band using T-DAB, concern about the
efficiency of the 1.5 GHz Band has been largely removed as a result of extensive
technical evaluation and field measurements, mainly by Canada’s Communications
Research Centre (CRC). It was found that indoor reception at L-Band is comparable to
that achieved at VHF frequencies. The reason is that the shorter wavelength at L-Band
offsets the increased attenuation through walls at the lower VHF frequencies.
efficiency of the 1.5 GHz Band has been largely removed as a result of extensive
technical evaluation and field measurements, mainly by Canada’s Communications
Research Centre (CRC). It was found that indoor reception at L-Band is comparable to
that achieved at VHF frequencies. The reason is that the shorter wavelength at L-Band
offsets the increased attenuation through walls at the lower VHF frequencies.
4.5.2
The Implications of Simulcasting
Whilst the benefits of digital broadcasting and the opportunities offered by this technology
are clear to broadcasters, there is concern about the time and cost implications of the
transition from analogue to digital. Until the coverage from digital broadcasts matches
that from existing FM and AM services, it is unrealistic to cut existing transmissions and
disfranchise listeners. It could be some years before the new digital services provide
comparable coverage and a receiver base is established. Only then can the analogue
services be closed down.
are clear to broadcasters, there is concern about the time and cost implications of the
transition from analogue to digital. Until the coverage from digital broadcasts matches
that from existing FM and AM services, it is unrealistic to cut existing transmissions and
disfranchise listeners. It could be some years before the new digital services provide
comparable coverage and a receiver base is established. Only then can the analogue
services be closed down.
The transition from analogue to digital is helped in many countries by cooperation
between public and private broadcasters, that jointly develop the necessary infra-
structure and create attractive new programmes, and suitable regulatory arrangements.
Examples of such cooperation exist in Canada, Sweden, the UK, France, Italy, etc.
between public and private broadcasters, that jointly develop the necessary infra-
structure and create attractive new programmes, and suitable regulatory arrangements.
Examples of such cooperation exist in Canada, Sweden, the UK, France, Italy, etc.
(1)
HD Radio (IBOC)
IBOC transmission schemes are particularly well suited for ensuring a smooth
transition to digital services. Since they are designed for compatibility with the
existing analog signals, there is little or no disenfranchisement of listeners at the
onset of service. New receiver costs are minimised since much of the existing
circuitry can be shared by the analogue and digital portions of the receiver. And
over time, as IBOC receiver penetration reaches a “critical mass,” individual
transition to digital services. Since they are designed for compatibility with the
existing analog signals, there is little or no disenfranchisement of listeners at the
onset of service. New receiver costs are minimised since much of the existing
circuitry can be shared by the analogue and digital portions of the receiver. And
over time, as IBOC receiver penetration reaches a “critical mass,” individual