In April 2008, the Australian Communications and Media Authority (ACMA) commenced a consultative review process that introduced reform of the 400 MHz Band.
One of the objectives of the review was to enable the provision of a dedicated, nationally harmonised allocation of spectrum to support improved government radiocommunications interoperability particularly for national security, law enforcement and emergency services. Interoperability is defined as the ability of users to communicate, by radio, with whom they need to, when they need to, when authorised.
The review was also essential to improve the efficient use of limited valuable spectrum and was underpinned by the ACMA strongly promoting the increased deployment and use of shared trunked radio networks and mandating a reduced channel bandwidth of 12.5 kHz (previously 25 kHz).
The results of the review and the impact for holders of licensed frequencies were announced in a discussion paper released in December 2010.
A national allocation for government use was achieved and all government users are required to be compliant with the 12.5 kHz channel bandwidth and have their licences within the government allocation over a pre-determined set of timelines.
To ensure a national approach to improving interoperability is supported, a government band plan for the dedicated allocation was developed by the National Coordinating Committee for Government Radiocommunications (NCCGR) and released in December 2011 with each of the government segments designated to support a particular service requirement.
The spectrum segments allocated to government and the total size of the allocation (less than currently used in NSW) will require significant change including the requirement to implement more spectrum efficient planning, processes and technology. Pressure to meet the compliance dates for transitioning also presents a number of implementation issues especially for users with old equipment deployed. The major impact being costs associated with transitioning spectrum assignments as this involves planning and engineering assessment as well as equipment upgrades and replacement where the age of the equipment renders it unable to successfully comply with the transition requirements.