World Broadcasting Unions Digital Radio User Manual - page 98

DIGITAL RADIO GUIDE

APPENDIX A: EUREKA 147

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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.

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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;

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Communications Laboratory Technical Note 99/01, ‘The impact of European and Canadian L-Band channel spacings 

on adjacent channel operation”, 20 April 1999.