Grundig Digital Radio manual Planning Parameters, ITU DSB Handbook

DIGITAL RADIO GUIDE APPENDIX A: EUREKA 147

The European CEPT channel plan encompasses four frequency bands, namely VHF Bands I, II and III and L Band. Allotments were made to allow the implementation of two Eureka 147 ensembles in any given country or area in Europe. The majority of these allotments were in VHF Band III and the lower part of the L Band (1452 MHz 1467 MHz). Allotments in the 230 240 MHz sub band of VHF Band III are subject to coordination with national defence users and the L Band was divided into terrestrial and satellite segments. Further consideration of L Band allotments was made at a second CEPT conference at Maastricht in 2002.

A second channel plan has been developed for Canada that covers only the L Band. This plan also provides for 23 channels, but with different guard bands to the CEPT Plan.

Comparing the characteristics of the two plans, the Canadian channel plan provides an interchannel guard band some 18% greater than the CEPT channel plan. Maximizing the spacing between adjacent channels is desirable, as this contributes to improved adjacent channel isolation which results in less stringent implementation constraints. In contrast, the CEPT channel plan trades off a larger interchannel guard band for increased guards at the band edges to facilitate sharing with other services operating near the band edges.

To facilitate receiver tuning and minimize scan times, manufacturers will assume, or at least prioritise, the use of certain centre frequencies as defined by the CEPT and/or Canadian channel plans. The use of ”non standard” frequencies could result in the need for manual tuning or, alternatively, require the receiver to undertake a complete scan of the band(s) based on the 16 kHz grid spacing. The latter is likely to take considerably longer and could be seen as a distinct disadvantage. Although manufacturers have been encouraged to incorporate the Canadian channel plan in their designs, it remains unclear what level of support will be afforded to the plan and whether there are cost implications for manufacturers in supporting both channel plans.

For Australia, there is a further complication if VHF Band III is used for digital radio. In this scenario, adoption of the Canadian channel plan would result in a ”mixed” frequency table arrangement (e.g., use of the CEPT channel plan at VHF Band III and the Canadian channel plan at L Band). In view of these uncertainties, adoption of the Canadian channel plan would appear justified only if significant benefits, in terms of improved adjacent channel isolation, were shown to be associated with the wider channel spacing of this plan. In the absence of any published data, the Communications Laboratory undertook measurements of the adjacent channel isolation afforded by the two channel plans, using a limited range of transmitting and receiving equipment available at that time. The results of these tests indicate no significant difference in adjacent channel performance.18

Planning Parameters

The planning parameters that could be used for the implementation of Eureka 147 services draw on a number of ITU and European sources:

The ITU DSB Handbook

EBU ”Technical bases for T DAB services network planning and compatibility with existing broadcasting services,” Document BPN 003 Rev. 1, May 1998;

18Communications Laboratory Technical Note 99/01, ‘The impact of European and Canadian L-Band channel spacings on adjacent channel operation”, 20 April 1999.

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