Radio quiet in the Mid West

Radio quiet zone

The Australian and Western Australian Governments have established a radio quiet zone to protect this world-class radio astronomy site while allowing for opportunities for coexistence with other activities in the region.

A radio quiet zone is an area in which signal levels from radiocommunications equipment (such as television transmitters, mobile telephones and CB radios) and electrical devices are controlled to limit interference to radio telescopes.

 A sign advises road users of the radio sensitive nature of the MRO.​
 A sign advises road users of the radio sensitive nature of the MRO.
 Boolardy Station and the Murchison shire is extremely sparsely populated.​
 Boolardy Station and the Murchison shire are extremely sparsely populated.

Why radio quiet?

Radio telescopes are designed to detect extremely faint radio signals from space. They are very sensitive to interference caused by other radio transmissions and electrical equipment. The remote Murchison region is one of the best sites in the world for radio astronomy as it has relatively few sources of interference compared with other more populated areas.

This webpage is intended to provide a general introduction to the radio quiet zone and is not a substitute for the relevant regulatory documents.

Radio quiet zone

The Australian and Western Australian Governments have established a radio quiet zone to protect radio astronomy while allowing for opportunities for coexistence with other activities in the Mid West region.

Centred on the Murchison Radio-astronomy Observatory (MRO), the Radio Quiet Zone comprises:

  • a 70km radius Inner Zone in which radio astronomy has primacy;
  • an Outer Zone from a 70km to 150km radius; and 
  • Coordination Zones up to a 260km radius (depending on frequency).
A three-level zoom map showing the position of the MRO and Boolardy station in Western Australia. The three zones of the Radio Quiet Zone with a map of the MRO underneath
Location of MRO and Boolardy Station within Australia

​Radio quiet diagram centred upon the MRO

 
Radio astronomy Inner Zone (0-70km)

The governments have agreed that radio astronomy is the primary use of spectrum within the 70km radius Inner Zone, with other activities considered secondary.

This is reflected in legislative, regulatory and policy instruments put in place by the Australian Communications and Media Authority (ACMA) and the Western Australian Department of Mines and Petroleum (DMP).

Radio astronomy Outer Zone (70-150km)

Within the Outer Zone (70 – 150km radius) the governments endeavour to maximise opportunities for coexistence between radio astronomy and other activities such as mining and pastoralism.

This is consistent with the legislative and regulatory instruments put in place by the ACMA.

Radio astronomy Coordination Zones (up to 260km radius)

A number of Coordination Zones extend the radio quiet zone up to a 260km radius (depending on frequency), as specified under the ACMA Radiocommunications Assignment and Licensing Instruction (RALI) MS32.

The table of zones, their radii and the relevant manager are listed in the "Regulations in the radio quiet zone" section below.

Centre point

The zones are measured from the centre point of the radio quiet zone at latitude 26° 42'15" South, longitude 116° 39' 32" East (GDA94 datum), about 350km north-east of Geraldton.

Regulations in the radio quiet zone

Licences for radiocommunications transmitters

Using a radio transmitter in Australia legally requires one of three types of licences.  Within the radio quiet zone these licences are regulated as follows:

Apparatus licences

Apparatus licences are required for most commercial or large radio installations, including satellite earth stations, television or radio broadcast towers, point-to-point radio links, radar, amateur radio, and maritime and aeronautical radiocommunications.

Applicants for apparatus licences in the radio quiet zone are required to consult with the MRO Entity (observatory site manager) about the impact of their proposed transmitter on radio astronomy. If interference from a proposed transmitter in the coexistence zone would exceed thresholds specified in the regulations, the applicant is required to undertake measures to reduce interference.

The relevant procedures and interference thresholds are set out in the Radiocommunications (Mid West Radio Quiet Zone) Frequency Band Plan 2011 and the Radiocommunications Assignment and Licensing Instruction (RALI) MS32.

Class licences

Common low power radio devices such as CB radios, satellite phones, wireless monitoring systems and most consumer devices such as WiFi and Bluetooth are automatically covered by a class licence. The relevant class licences contain special conditions applicable to the radio astronomy Inner Zone to prevent interference to radio astronomy.

Spectrum licences

Spectrum licences typically apply to a group of transmitters operated by service providers such as mobile telephone companies rather than individual installations. The ACMA has placed conditions on relevant spectrum licences to limit interference to radio astronomy.

For more information contact the Australian Communications and Media Authority (ACMA).

Mining and exploration

Exploration within the 70km radius Inner Zone must be conducted according to an approved Radio Emissions Management Plan that demonstrates that the proposed operation will be consistent with radio astronomy requirements.

Within the Radio Quiet Zone there are also two areas of land reserved under Section 19 of the Mining Act (WA), which are exempt from the granting of mining tenements.

For more information contact the Department of Mines and Petroleum.

Zone names in regulations

The following table identifies how the main areas of the radio quiet zone are referred to in the regulations.

​Distance ​Main areas of zone ​Zone names in regulations ​Administering Authority
0-70 km​ ​ ​ ​Inner zone ​ ​

​Radiocommunications (Mid West Radio Quiet Zone) Frequency Band Plan 2011

  • 70km radius Inner Zone
​ACMA ​

​Radiocommunications Assignment and Licensing Instruction (RALI) MS32

  • 70km radius Inner Zone

​Radio Telescope Mineral Resource Management Area (RTMRMA)

  • 70km radius area depicted as File Notation Area 7618 in Tengraph
​DMP
​70-150 km ​Outer zone

​Radiocommunications (Mid West Radio Quiet Zone) Frequency Band Plan 2011

  • 150km radius Outer Zone
​ACMA
​Up to 260 km ​Coordination zones

​Radiocommunications Assignment and Licensing Instruction (RALI) MS32

  • 'coordination radii' vary from 70km to 260km, depending on frequency
​ACMA
 

 

Facilitating coexistence

Within the Outer Zone (70 – 150km radius) the goal of the governments is for both radio astronomy and other activities to be successfully undertaken to maximise opportunities to the region.  While still providing protection for radio astronomy, the governments will work with industry and the scientific community to facilitate the continued development and viability of other economic activities in the region through encouraging negotiation of mutually agreeable strategies to control radio frequency interference.

The process to achieve the goal is a consultative approach whereby:

  • the proponent consults with the MRO Entity with a goal of developing and implementing technical solutions that ensure the radio-frequency impact of their operation on radio astronomy falls within acceptable limits; and
  • the MRO Entity facilitates practical solutions that maximise opportunities for shared use of spectrum within acceptable limits. This might include engaging in collaborative technical work with the proponent to develop mutually acceptable solutions.

Decision-Process1.jpg 

A summary of the three main steps when applying to the ACMA for an apparatus licence in the Outer Zone and Coordination Zones. A similar process applies when submitting an exploration or mining proposal relating to the Radio Telescope Mineral Resource Management Area to DMP. (Click to see larger version.)

What if thresholds are exceeded?

If the proposed activities in the Outer Zone or Coordination Zones are likely to cause interference above thresholds defined in the RALI MS32, the proponent and MRO Entity are encouraged to work together to develop and agree on a mutually acceptable technical solution.

The solution should minimise the impact on radio astronomy while maximising the opportunity for shared use of radio spectrum within acceptable limits.

What can the technical solution involve?

Technical solutions that would mitigate interference may include, for example, power reduction, site relocation, directional antennas, alternative frequencies, optical fibre or operating devices only at certain times.

Who makes the decision?

The Australian Communications and Media Authority (ACMA) makes the final decision as to whether a radiocommunications licence will be granted.

Proponents and the MRO Entity can each advise the ACMA, but the ACMA is not bound by their advice, nor that of any other stakeholder.

Is an agreed technical solution always possible?

It may not always be possible for the MRO Entity and a proponent to agree on a technical solution due to the impact of proposed activities on radio astronomy or the impact of proposed interference mitigation measures on the proponent. 

According to ACMA regulation, in cases where agreement cannot be reached the proponent can still apply for a licence to the ACMA and the ACMA will decide whether to issue a licence, having regard to all matters it considers relevant and taking into account the requirements of all stakeholders. If a mutually satisfactory technical agreement has been reached with the MRO entity, this will be a relevant factor for the ACMA in its decision making.

Will licences be renewed?

Under the terms of RALI MS 32,  licences granted under a licence agreement between the MRO and a third party will be considered for renewal consistent with the obligations under the Radiocommunications Act 1992 and the ACMA’s apparatus licence renewal policy. Any agreements reached will not be required to be renegotiated at the time of licence renewal, unless stated in the agreement or if the licence agreement has a limited time period.

Further information regarding licence renewals can be found in section 4.7 of RALI MS32.

Where should I go for more information?

This website provides an introduction to radio quiet and coexistence. For more detailed information follow the links in the table below.

Who am I?​ ​Where should I go for more information?

​Prospector or miner

Department of Mines and Petroleum

​Apparatus licence applicant

Australian Communications and Media Authority (ACMA)

Contact CSIRO, the MRO Entity, as early as possible to discuss your proposal.

​Local pastoralist

See the frequently asked questions prepared by CSIRO.

Contact CSIRO, the MRO Entity, if you have questions.

​Emergency services provider

Australian Communications and Media Authority (ACMA)

Note that the Radiocommunications Act 1992 allows for operation of radiocommunications devices in urgent situations involving safety of life, major environmental threats or significant damage to property.

​Local resident, visitor or tourist

​See the frequently asked questions prepared by CSIRO.

Contact CSIRO, the MRO Entity, if you have questions.

​Other stakeholder

​Contact the Australian SKA Office within the Commonwealth Department of Industry and Science or the Office of Science within the Western Australian Department of the Premier and Cabinet.

​Radio astronomer

​Contact CSIRO, the MRO Entity.

 

 

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