Anche la Nuova Zelanda sta studiando la creazione di una infrastruttura di radio digitale DAB+. Il problema sta nelle frequenze di banda III ancora occupate dalla tv analogica. Si pensa di attendere la possibile data del 2012 per lo spegnimento di quest'ultima e intanto di utilizzare il segmento superiore della banda, tra 230 e 240, chiedendo ai militari di abbandonare quel segmento.
Effort to speed up digital radio in NZ
The Economic Development Ministry will decide soon whether to fast-track the introduction of digital radio by using air waves now reserved for the military.
State-owned transmission company Kordia has been testing digital audio broadcasting (DAB) transmissions in Auckland for more than year and has opened up its trials to commercial broadcasters.
Radios that use DAB – and its latest variant, DAB+ – can "pause and rewind" live radio and call up stations by name from an electronic programming guide. They should also provide better reception.
Economic Development Ministry radio spectrum manager Brian Miller says the preferred long- term home for DAB broadcasts would be in VHF Band 3 at between 175MHz and 230MHz.
This spectrum is now used for television broadcasting and cannot be freed up till analogue television services are shut down.
Broadcasting Minister Trevor Mallard said in December that a date for the closure of analogue TV would be set once three- quarters of TV viewers had switched to Freeview or Sky, or 2012 – whichever came first.
Unless a temporary home can be found for digital radio on New Zealand air waves, it is unlikely to be offered to the public till then.
Mr Miller says the ministry is considering whether spectrum reserved for the military in the 230-240MHz band could be made available in the interim. It would be sufficient for "at least tens" of digital radio stations, though the number would depend on their "bitrate", which would determine the quality of reception.
The alternative option of broadcasting digital radio using spectrum in the 1.5GHz band is not highly favoured by broadcasters because higher frequency radio signals cannot be picked up so easily indoors, he says.
Kordia business manager Aaron Olphert says the state- owned enterprise is pushing for access to the 230-240MHz spectrum but is "at the mercy of the Economic Development Ministry". DAB+ transmissions could easily be switched to VHF Band 3 once it became available, he says.
"Pretty much all the transmission equipment we'd put in place is retunable, so there is no problem there. From a consumer point of view – unlike things like changing an analogue TV where you have to go through quite a complicated process to retune – all you do is push the 'auto tune' button on the front of the radio and it will take five seconds."
Commercial broadcasters have been talking up an alternative digital radio standard, HD radio, which could be broadcast using their existing FM licences. This would protect their current investments in the crowded FM spectrum range and shield them from the threat of new competition from DAB+ broadcasters.
But a question mark hangs over the cost and availability of HD radios. These are popular only in the United States and HD radios made for the US market would not work here.
Norm Collision, director of engineering at The Radio Network – the largest commercial broadcaster – said in December that if the commercial radio industry backed the DAB+ standard, it would push for similar incentives to those provided to private broadcasters in Australia. These included a moratorium on new competition, government funding to meet migration costs, and free spectrum.
Mr Olphert says Kordia is working with commercial broadcasters to get a channel on air using the DAB+ standard as part of its Auckland trials. It has also just put a second test transmitter on the Sky Tower.
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