Document ID: chunk:federal_register_of_legislation:F2023C00620:body:0:p5
Version: federal_register_of_legislation:F2023C00620
Segment Type: other
Provision Reference: 
Character Range: 12054–15286

unwanted emissions depend on both the nearness of, and the operating frequencies of, radiocommunications transmitters and radiocommunications receivers that are close in terms of both frequency and distance.  In addition, out-of-band interference:

         (a) can extend for many Megahertz either side of the frequency boundary of a spectrum licence;
         (b) is dependent on the quality of the radiocommunications receiver as well as the levels of the radiocommunications transmitter emission; and
      (c) is difficult to model accurately.

      (2) If emission limits were used to manage out-of-band interference for devices in close proximity, the interference modelling inaccuracy would require large probability margins to be added to those limits.  These margins would place severe constraints on use of the spectrum because the frequency boundaries of a licence extend throughout the entire geographic area of a licence. Therefore, emission limits that manage out-of-band interference throughout the geographic area of a spectrum licence cannot be used because they would lead to a severe loss of utility of the spectrum on both sides of the frequency boundary.

      (3) Instead of making large tracts of spectrum space unusable through the imposition of emission limits, out-of-band interference is managed through interference management procedures based on a compatibility requirement for radiocommunications receivers.  A minimum level of receiver performance is specified in conjunction with the compatibility requirement because the performance level of receivers:

         (a) affects the level of interference; and

         (b) can vary for receivers operating under spectrum licences.

           Note: The compatibility requirement is set out in Part 4.

      (4) High power radiolocation services in the 3100-3500 MHz band are operated by the Department of Defence on an itinerant basis. These radiolocation services have the potential to disrupt the throughput of 3.4 GHz receivers particularly on the uplink channel (base station receiver).  The Department of Defence already employ techniques to minimise impacting other in-band and adjacent band services. However, there will be occasions when interference cannot be fully mitigated by these techniques.  In such instances the interference may be due to receiver blocking, strong out of band emissions of the radar, or other susceptibilities within a 3.4 GHz fixed or mobile wireless network configuration.  When planning service deployments, spectrum licensees are urged to consider different engineering techniques to reduce the likelihood of impact to their spectrum licensed service.  Such engineering techniques by spectrum licensees may include additional RF filtering, network redundancy, or resilience of network configuration where vulnerabilities to radar signal interference are identified.  The ACMA will work with the Department of Defence to provide what additional information it can to assist spectrum licensees on this matter. Such information will only be given directly to existing or likely prospective spectrum licensees.

      3.3 Recording radiocommunications receiver details in the Register

      A radiocommunications