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450-470 MHz band alignment

Annex C: Band Plan Rationale

From the band plan diagram, it can be seen that we propose to realise the alignment in a phased process.

We have chosen to set basic constraints on the way the alignment is achieved:

paired blocks must be positioned 10 MHz apart;

each block moves only once; and

each move puts a block into vacant spectrum where possible.

There is a limit to the moves that are possible at each stage, since in general each move is facilitated by those that have preceded it.

Of the various block allocations within the band, two are of particular interest since they do match the CEPT Recommendation. One of these is the small allocation for maritime on-board15 use at 457 MHz and 467 MHz. These two blocks are the same size and are spaced 10 MHz apart. They are also international allocations so it is not feasible to move them. The other allocation in this category is the single 25 kHz paging channel at 466.075 MHz. This is an allocation used in various countries in Europe, although use in the UK has ceased. Paging is effectively base transmit, and this channel is already in the upper half of the band. For the time being, this channel will remain in reserve.

There are other blocks that appear to be spaced at 10 MHz, but these blocks are not paired with each other.

There is a 1 MHz block used by Short Range Devices (SRDs), which are licence-exempt. It is not feasible to move this block over the timescale of this project, so all moves will occur around this block and it will remain intact.

To begin the alignment, first we are looking for blocks that can be moved to create holes with 10 MHz spacing. There is a hole at 464-467 MHz and another at 450-453 MHz, so we can either:

a) move something from within 454-457 MHz and so create a hole in this range; or

b) move something from within 460-463 MHz.

The CEPT Recommendation, as well as defining the configuration for 450-470 MHz, also identifies the band 440-450 MHz as being for simplex (single-frequency) usage. RA has been negotiating with the Ministry of Defence to gain greater access to military spectrum in 410-450 MHz. Civil access to some single-frequency channels on a national basis within 440-450 MHz has recently been granted.

There is currently a block of Wide-Area Paging, which is single-frequency base transmit, at 454 MHz. Since this is single-frequency usage, it should be positioned in channels between 440 and 450 MHz.

The proposed process for the alignment is as follows:

Step 1

The single-frequency European Wide-Area Paging channel lies within the Emergency Services allocation that will become vacant after migration. This channel is not used at present in the UK, but the channel will continue to be held in reserve for the time being. The first move of the plan is to migrate the 454 MHz Wide-Area Paging block to new dedicated national channels between 440 and 450 MHz. This creates a hole at 454-455 MHz, which can be paired with the ex-Emergency Services hole at 464-465 MHz. Which block to move next? We have to think what paired holes can be created as a result of each move.

Step 2

Within the band there are two pairs of blocks for PMR (used for duplex services) and one block for single-frequency assignments. Within the paired PMR blocks there are a number of channels that, as well as being duplex channels, also exist as independent single-frequency channels. The second phase is to move the purely duplex assignments in one of these pairs (456-457 MHz/461.5-462.5 MHz) so that the base-receive leg moves into the spectrum vacated by Wide-Area Paging at 454 MHz and the corresponding base-transmit leg to ex-Emergency Services spectrum at 464 MHz. Not all the channels in the existing block contain assignments, and additionally there will be some spectrum yield as a result of using new and better spectrum assignment techniques. This block will therefore fit into less than 1 MHz.

15 ITU-R Radio Regulations Article 5.287 states, ‘In the maritime mobile service, the frequencies 457.525 MHz, 457.550 MHz, 457.575 MHz, 467.525 MHz, 467.550 MHz and 467.575 MHz may be used by on-board communication stations. Where needed, equipment designed for 12.5 kHz channel spacing using also the additional frequencies 457.5375 MHz, 457.5625 MHz, 467.5375 MHz and 467.5625 MHz may be introduced for on-board communications. The use of these frequencies in territorial waters may be subject to the national regulations of the administration concerned. The characteristics of the equipment used shall conform to those specified in Recommendation ITU-R M.1174 (see Resolution 341 (WRC-97)).’

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