The 400 MHz band is mainly used for the land mobile service, but also accommodates other services including the fixed (point-to-point and point-to-multipoint), radiolocation and amateur services.
The 400 MHz band is congested in the major capital cities. In response to this and requests from industry and users of the band, the ACMA began a review the band in 2008 with the broad objectives of implementing measures to:
- improve government spectrum harmonisation to facilitate more efficient government networks and improved interoperability
- improve the efficiency with which the band is allocated and used
- facilitate new technologies and complementary uses
- minimise the need for ongoing ACMA intervention in the band.
One of the key achievements of the review is the provision of harmonised spectrum for use by government agencies. The Australian Communications and Media Authority (the ACMA) believes strongly that dedicated harmonised spectrum of appropriate size and structure is critical to enabling interoperable radiocommunications between national security, law enforcement and emergency services. The spectrum arrangements put forward in this paper are likely to mark the beginning of a new era in government radio networks, with the emergence of large, efficient networks that provide a greater level of support for emergency services and other vital government objectives than is currently the case. The new arrangements create a significant and rarely delivered opportunity for government organisations to develop a nationally harmonised and interoperable system of government radio networks able to deliver effective radiocommunications on a national scale.
Under the new arrangements, several segments in 403–470 MHz have been identified for the exclusive use of government, primarily to support national security, law enforcement and emergency services, but also available to support broader government use once these requirements are met. The ACMA has developed these arrangements in close consultation with individual stakeholders, relevant committees and peak industry groups. The final arrangements complement the objectives developed by these groups and the Council of Australian Governments (COAG) agreed national framework for improved radiocommunications interoperability.
As well as substantial changes to the overall structure of the band through the creation of harmonised government spectrum and revised frequency splits, the outcomes of the review include improvements to underlying technical arrangements in the band. This includes a reduction in channel bandwidths and updates to the assignment and coordination rules.
Another key outcome of the review is an increase in the technology options able to be supported in the band. Changing the frequency duplex arrangements in the 450–470 MHz band and changing the channelling scheme opens up options for technologies requiring such arrangements. These systems were not supported under previous arrangements.
The ACMA intends to finalise transition to the new arrangements by 31 December 2015 in areas where congestion is defined, and by 31 December 2018 outside of these areas.
For additional information on the 400 MHz band see:
- Planning developments 403-520 MHz Band
- Related papers:
- The way ahead – Timeframes and Implementation Plans for the 400 MHz Band
- IFC 11/2010 The way ahead - Decisions and implementation options for the 400 MHz band
- IFC 08/2009 Spectrum Proposals: 403-520 MHz - Proposals for future arrangements in the 400 MHz band
- IFC 06/2008 Spectrum Options: 403–520 MHz - Initial consultation on future arrangements for the 400 MHz band
- RCC 400 MHz Review Working Group
- 400 MHz Road Show
- A guide to changes in the 400 MHz band