Unused spectrum in New Zealand

The Radio Frequency Users Association of New Zealand is undertaking research to show that there's not as much spectrum to go around as some people might think.

Who would have imagined it just a few years ago - all analog television closed down, finished, gone, never to be seen again. Now everyone is using digital TV, either through a terrestrial network or via a satellite. Gone are the days of large Yagi antennas on rooftops, sometimes snowy pictures and ghosting in hilly locations. Now the TV picture is crystal clear or it disappears altogether, and most viewing is on a widescreen device. This is a project that seems to have proceeded amazingly smoothly, with excellent project management and cooperation by the New Zealand regulator and broadcasters.

But a real bonus is that TV broadcasting is now much more spectrum efficient and has freed up significant amounts of spectrum for other uses. This spectrum is in three frequency bands: Band 1 (44-68 MHz), Band III (174-230 MHz) and Upper UHF (694-806 MHz).

In New Zealand, the most sought after spectrum was the new 700-800 MHz band. This has been auctioned off to the three incumbent cellular operators for new 4G LTE cellular systems and is expected to be released for use in 2015.

In the Band 1 area, there is little demand but 50-51 MHz has been released back into the amateur 6-metre band. In addition, the Ministry of Business, Innovation and Employment (MBIE) has recently released a discussion paper covering the implementation of radio-controlled toys at 49 MHz. The propagation characteristics of this band somewhat restrict its usefulness.

The Band III spectrum is far more useful to a number of parties with its excellent propagation characteristics. It could be used for mobile radio, radio microphones or digital audio broadcasting (DAB), to name just a few. Radio microphones are probably better suited to UHF to enable more efficient frequency re-use and there has been little interest expressed in DAB to date, even though there have been a couple of pilot broadcasts operating in Wellington.

Which leaves mobile radio. As most people will realise, mobile radio is at the heart of our community - without it our community would likely ground to a halt, emergency services would be constricted, public transport and utilities could not operate. While some may think that mobile radio is dying since the advent of smartphones, this is far from the case. In the recent Christchurch earthquakes and previous significant weather events, mobile radio was shown to be the one technology that did not block or degrade, but just kept providing continuous communication. In addition, demand for handhelds with infill coverage is increasing, as are health and safety requirements. Quirks in the MBIE licensing regime appear to be hiding the increasing demand due to multiple channels on the same licence.

MBIE regulators consider that there is no shortage of available channels for mobile radio and furthermore, there will be additional channels available as a result of the 25-12.5 kHz channel spacing conversion. RFUANZ disagrees with this response and has commenced some research to prove otherwise - all members of the industry are urged to get behind the RFUANZ initiative to ensure all relevant information is available.

Bruce Harding is chairman of the Radio Frequency Users Association of New Zealand (rfuanz.org.nz). The association was formed in 1990; its membership spans the gamut of operators and interested parties in government and private industry.