Australia makes ready for D-Star

The United States is not the only place where digital voice repeaters are coming of age. Australia's National Technical Advisory Committee or NATC has been considering how best to accommodate narrow band digital voice technologies such as D-Star. They have now made a number of proposals.

Peter Young, VK3MV, of the WIA News reports:

Firstly, in the 2 meter band, digital repeaters will be assigned to frequencies in the 146 to 147 MHz band, using the space between existing FM repeater channels. This is known as inter-leaving and is a common method of assignment to increase spectrum efficiency.

The are some compelling reasons to take this approach for 2 meters, one is to remove the potentially annoying “drone” of digital signals, and secondly, the lack of normal FM repeater channels in some parts of Australia. It also seems to make sense to have the uniform arrangements across all of Australia.

The arrangements for simplex operations, again to separate digital and FM emissions, NTAC has recommended the best area for simplex D-Star activity would be the 145 MHz segment. One suitable channel that is clear of other use is 145.125 MHz and should be used as the national simplex digital channel.

On 70cms, where there is less congestion, NTAC has recommended that the first fifteen repeater channels, that is, 438.025 to 438.375 MHz, be used for D-Star type activity.

NTAC has recommended that the arrangements for simplex activity on 70cm be centred on a national channel of 438.900 MHz, with secondary channels 12.5 KHz either side of the national channel.

For the 23cm band, NTAC has recommend that repeater channels be assigned in the high end of the 1293 to 1294 MHz repeater segment. And on the 23cm, there is already a digital simplex segment between 1298 and 1300 MHz. As D-Star on this band uses a 128 KHz emission bandwidth, it is suggested that channels are spaced at 200 KHz intervals, beginning at 1298.1 MHz.

Peter Young VK3MV

Australia's National Technical Advisory Committee will review these arrangements as D-Star digital activity develops.

Further information can be found on the WIA website and will be included in the next edition of the WIA call book.

Source: ARNewsline, WIA News