3. Land mobile systems in other administrations

Worldwide, a number of digital LMR technologies are available, including the European TETRA (ETSI) platform, DMR (ETSI), the American APCO P25 (TIA) and proprietary equipment. Most countries have adopted 12.5 kHz channel plans to host digital technologies in the VHF and UHF bands, with the exception of those countries implementing TETRA (25 kHz) in the UHF band. There has also been a strong drive to open up the licensing of 6.25 kHz systems. In regards to channel plans, a mixture of approaches can be found across administrations, reflecting the legacy of band plans implemented for early analogue LMR technology using 25 kHz channel spacing in the VHF spectrum.

In the United States, the FCC mandated a deadline⁹ in 2004 for 25 kHz land mobile systems operating between 150 MHz and 512 MHz to migrate to 12.5 kHz technology. The deadline was set to 1 January 2013. This decision was designed to promote the utilisation of more spectrally efficient technologies. The minimum requirements are one voice channel per 12.5 kHz of bandwidth, or a data rate of 4800 bps per 6.25 kHz (9600 bps for 12.5 kHz; 19.2 kbps for 25 kHz). New systems or modifications to existing 25 kHz systems are not permitted under this mandate from 1 January 2011. Digital LMR is already being licensed in the United States with channel widths of 12.5 kHz and 6.25 kHz (FDMA and TDMA formats).

In Europe, the EC decision of 7 July 2006 details the bands available for digital LMR in the VHF and UHF bands¹⁰. The decision specifies guidelines for the implementation of digital LMR systems using channel spacing of up to 25 kHz. It also specifies the applicable ETSI harmonised standards for the purpose of technical compliance (EN 300 113-2, EN 300 390-2, EN 303 035-1, EN 303 035-2). TETRA systems are also available in the lower UHF bands (400 MHz). However, by specification, TETRA technology requires a minimum transmit-receive frequency split of 10 or 45 MHz. The current configuration of the New Zealand trunked dispatch bands in the 400 MHz UHF spectrum provides a split of 8 MHz. This frequency split precludes TETRA services from being implemented in the 400 MHz spectrum in New Zealand, unless the bands are reconfigured for a wider split.

In Australia, ACMA has published a technical document entitled RALI LM 8¹¹, which specifies the licensing requirements and coordination procedures for single and two-frequency LMR systems. The document includes analogue and digital systems in the VHF and UHF bands. The only provision made regarding digital LMR is that new digital LMR systems are to be engineered and certified with appropriate consideration of interference protection for legacy analogue systems.

Question 2

Should New Zealand adopt a similar approach to that of the United States by planning a deadline for all 25 kHz analogue LMR systems to migrate to the more efficient 12.5 kHz channels? If yes, then what would be a reasonable timeframe?

Question 3

Do you foresee a need to accommodate TETRA systems in bands other than 800 MHz in New Zealand? If so, which bands and why?

 Footnotes

⁹The FCC mandate, specified in Part 90 of the Code of Federal Regulations, can be found at: http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-04-292A1.doc.

¹⁰The EC decision can be found at: http://www.erodocdb.dk/Docs/doc98/official/pdf/ECCDEC0606.PDF.

¹¹RALI LM 8 can be found at: http://www.acma.gov.au/WEB/STANDARD/pc=PC_2609.