Looming Loss of 2300-2302 MHz – WIA Fights back !

As advised in February, the Australian Communications and Media Authority (ACMA) proposes to withdraw the 2300 to 2302 MHz segment of the 13 cm Amateur band from July 2015 so that it can be re-allocated for Spectrum Licensing nationally. All Advanced Amateur licensees will be affected. The ACMA has already advised all Advanced licensees by letter and invited comment on the proposal.

The driver behind the ACMA’s proposed move is to create a tidy 100 MHz-wide band from 2300 to 2400 MHz for the purpose of Spectrum Licensing by auction. It is understood that the likely technology to be deployed under Spectrum Licensing in this proposed band will be that known as Long Term Evolution (LTE). The 13 cm Amateur band has only a secondary service status at 2300 to 2450 MHz. Primary user status goes to the fixed, mobile and radiolocation services. 2400 to 2450 MHz is widely used by Class Licensed Wi-Fi wireless computer networks and radio amateurs have to share the use of this sector of 13 cm, with the inevitable rise in the noise floor and interference issues. The 2300 to 2302 MHz segment has been used for narrowband, weak-signal working and this is reflected in the WIA bandplan for 13 cm.

In the face of the ACMA’s proposal, the WIA intends to fight back.

The WIA is preparing a submission that strongly argues for the retention of a 150 kHz-wide allocation at 2300 MHz on at least a co-primary basis. A 150 kHz-wide “line in the sand”, you might say. Some have suggested that the Institute should bargain the loss of 2 MHz in the 13 cm band for more spectrum elsewhere – like the 80 metre DX window, or securing exclusive access to 50 to 52 MHz, for example. However, the WIA Board has adopted the stance that this is no time to “roll over and die” on the 13 cm issue, to use the loss of 2 MHz as a bargaining chip when it comes to issues affecting other bands – or, for that matter – bargaining for a new band elsewhere in the radiofrequency spectrum. Each issue really has to be addressed on its own merits.

The Institute will continue to seek from the ACMA more favourable consideration in other amateur bands under threat or other disadvantage, along with new allocations.

LTE employs complex modulation technology to provide very high capacity and data speed in new cellular mobile networks. The spectrum used by LTE may be configured in channels of various widths, ranging from 1.4 MHz up to 20 MHz wide. Hence, many channels will fit within the proposed 100 MHz band at 2300 to 2400 MHz. The good news for us is that the whole of a channel’s bandwidth is not used. There is some unoccupied spectrum at the edge of each channel, regardless of what channel bandwidth might be deployed. For the minimal channel bandwidth of 1.4 MHz, the unoccupied spectrum at each edge – or “white space”, if you like – amounts to 160 kHz. For a 10 MHz channel, it’s 500 kHz at each edge. So – there will always be some unoccupied and otherwise unused spectrum right at 2300 MHz. Hence, the WIA submission proposes that a 150 kHz-wide allocation, from 2300 to 2300.15 MHz, is retained for Amateur use on at least a co-primary basis. The proposed arrangement is illustrated in the diagram here.

In addition, the 10 MHz immediately below 2300 MHz, from 2290 to 2300 MHz, is allocated in Australia for weak-signal space research, fixed and mobile services. Australian Defence systems in that band are protected against harmful interference. It is envisaged that Spectrum Licensees using the 2300 to 2400 MHz band will be required to reduce out-of-band emissions below 2300 MHz to meet a specified standard, tailoring-off the transmission power and bandwidth usage so as to protect licensed users of the 2290 to 2300 MHz band from interference. This, too, works in our favour in arguing to retain a segment of the 13 cm band for narrowband, weak-signal working, be it terrestrial point-to-point DX, rainscatter propagation or moonbounce.

The WIA submission notes the significant loss of segments of Amateur allocations in the 70 cm, 23 cm and 9 cm bands. It also emphasises the long history of leading edge weak-signal terrestrial, space (EME and satellite) and ATV work carried out on the 13 cm band over more than 60 years, since the band was allocated following WW II. Many state/territory and national distance records have been established and re-established over the decades and are recognized around the globe. In addition, there are currently at least two Australian suppliers of high performance transverter kits for the 13 cm band. Use of the band is relatively popular among stations deploying microwave equipment on field days.

The submission argues that loss of 2300 to 2302 MHz would, at best, severely hamper – or at worst – eradicate weak-signal terrestrial and moonbounce work by Australian radio amateurs. This is about preserving a future for leading edge weak-signal Australian amateur radio work in this region of the microwave spectrum. The Institute encourages all interested licensees to respond to the ACMA’s invitation to comment.

You might develop your own detailed submission, and/or you might care to write to the ACMA and support the WIA’s submission. It is in the interests of the future of amateur radio in Australia. The deadline for comment is close of business on Wednesday 27 March. A link to the ACMA’s consultation paper is provided below.

ACMA Consultation Paper re 2300-2302 MHz Link

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