7Background

7 Background

(1) The 2.5 GHz band has been allocated for spectrum licensing. Spectrum licensed, apparatus licensed and class licensed radiocommunications transmitters communicate with radiocommunications receivers in and adjacent to the 2.5 GHz band. These receivers may suffer interference from unwanted emissions, blocking and intermodulation caused by a radiocommunications transmitter operated under a 2.5 GHz spectrum licence. (2) This instrument has been made to provide guidance on the management of interference from radiocommunications transmitters operated under a 2.5 GHz spectrum licence to: (a) spectrum licensed receivers operating in the 2.5 GHz mid-band gap, typically used for ENG (Part 3); (b) apparatus licensed receivers used for fixed services, operating in and adjacent to the 2.5 GHz band (Part 4); (c) apparatus licensed receivers used for space services, operating in the frequency bands 2483.5 MHz to 2500 MHz and 2690 MHz to 2700 MHz (Part 5); (d) apparatus licensed receivers used for ARS, RLS and the Department of Defence, operating in the frequency band 2700 MHz to 2900 MHz (Part 7). (3) This instrument also provides advice (Part 6) on the following: (a) the notification of sites to assist in the protection of radiocommunications receivers used for radio astronomy services, operating in the frequency bands 2500 MHz to 2550 MHz and 2655 MHz to 2700 MHz, on a fortuitous basis; and (b) coordination with the ARQZWA. (4) As radio waves propagate in different ways because of factors such as frequency, terrain, atmospheric conditions and topography, there are a number of ways to predict path loss. The ITU-R Recommendation P.1144 “Guide to the application of the propagation methods of Radiocommunication Study Group 3” provides a guide on the application of various propagation methods developed by the Radiocommunication Sector of the International Telecommunication Union. It advises on the most appropriate methods for particular applications, as well as the limits, required input information and output for each of these methods. The most recent version of propagation models developed by the Radiocommunication Sector of the International Telecommunication Union should be considered when modelling propagation in the 2.5 GHz band.

Note 1: ITU-R Recommendation P.1144 is available, free of charge, from the International Telecommunication Union’s website at www.itu.int.

Note 2: The use of other published propagation models applicable to the 2.5 GHz band may also be suitable.

(5) The ACMA may take this instrument into account in determining whether a radiocommunications transmitter operated under a 2.5 GHz spectrum licence is causing interference to an apparatus licensed or class licensed radiocommunications receiver operating in circumstances set out in this instrument. (6) This instrument does not prevent a person negotiating and implementing other protection requirements with other persons.