Technical Planning of VHF-FM Frequencies
The Ministry has recently undertaken a technical planning exercise in order to be able to provide the optimum licences for the upcoming 20 year period from 2011. The offer of new licences provides an opportunity to implement a preferred long term plan for the upcoming 20 years. Planning for licences suitable for VHF-FM broadcasting involves a "block and group" scheme where it is desirable to keep all licences at a site (and other sites serving largely the same area) in a common group. This gives a consistent frequency separation of 0.8 MHz (or multiples of this separation) between licences at the same site (or serving the same area).
By way of explanation, a "group" is identified by a letter A, B, C etc, while a "block" has a number 0, 1, 2, 3 etc. A low frequency (88.2 MHz) is designated A0, the next (0.1 MHz above) is designated B0, then C0 etc, and after H0 the next frequencies are contained in the next block and are designated A1 (89.0 MHz), B1, C1 etc until the frequency H1, when a further block is used commencing with designation A2 (89.8 MHz). The designation process repeats through the entire 88-108 MHz range up to Block 24.
The recent planning has rationalised situations where past licences at a site had used frequencies from different groups and has, in some instances, adopted a different group for a site to minimise adjacent area incompatibility. This means that the offers of new licences for the period beyond 2011 may have different frequencies to those in use today. Other parameters such as maximum power and radiation pattern are generally unchanged. The possibility of frequency changes was identified in earlier public consultation documents on the policies to be adopted upon the expiry of rights. Whilst most sites now only utilise frequencies from a single group, there are areas (notably Northland) where the use of synchronous broadcasting requires a departure from this principle.
Where appropriate the planning has incorporated the experience derived from the present trials of licences using a narrower separation (trials have operated in Auckland and Wellington for some time), but the Ministry recognises that further work is desirable (and is planned) to determine the situations where further narrow separations might be used, whilst protecting the coverage of existing licences and the potential for future digital broadcasting services.
The planning work has been done in parallel with the wider policy process of determining recommendations to Government on the Discussion Paper published in 2005. The planning work has assumed that the extension to the frequency band at the lower edge will proceed prior to 2011, and that the moratorium on licences in the upper band will also be removed by that time. The planning will need to be revised if the final Government decisions are different from the parameters used for planning.
The overall plan is contained in a number of worksheets. In some cases it is necessary to consider several sheets to evaluate the choice of the frequency group assigned to a particular site. It should be noted that the reservations or licences for the Governments four priority programmes have been made in Block 16 to 19 and in some areas in Block 20 to 23. In the new plan only modest use of Block 20 to 23 is required.
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FM Band Plan (Version 8)
[ Published 24 April 2007 ]
This technical planning document identifies the blocks and groups within 50 geographical areas in New Zealand. The front page defines the "block and group" frequency raster.
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Archive
Older, superseded technical planning documents.
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