Wireless LANs in the 2.4 GHz band FAQ | ACMA

Wireless LANs in the 2.4 GHz band FAQ

Accessing the public telecommunications network and related issues

These FAQ are about wireless LANs operating in the 2.4- 2.4835 GHz radiofrequency band accessing the public telecommunications network and related issues

What types of devices use the 2.4GHz Band?

Various applications use the 2.4 GHz band including:

  • WLAN systems (some from IEEE 802.11b & g)
  • cordless phones
  • wireless medical telemetry equipment
  • Bluetooth ™ short-range wireless applications

For more information:

Industrial, scientific and medical (ISM) applications also use the 2.4 GHz band. The most common ISM equipment in the 2.4 GHz band is the domestic microwave oven.

Radiocommunications services operating in ISM-designated bands must accept any harmful interference caused by ISM applications.

What radiated power limits apply to devices operating in the 2.4 GHz band?

For operation of devices under the LIPD class licence a maximum radiated power of:

  • four watts EIRP is authorised in the 2.4 – 2.4835 GHz band for digital modulation transmitters
  • 500 milliwatts EIRP is authorised in the 2.4 – 2.4835 GHz band for frequency hopping transmitters that use a minimum of 15 hopping frequencies
  • four watts EIRP is authorised in the 2.4 – 2.4835 GHz band for frequency hopping transmitters that use a minimum of 75 hopping frequencies
  • one watt EIRP is authorised in the 2.4 - 2.45 GHz band for telecommand and telemetry transmitters and radiofrequency identification transmitters
  • 10 milliwatts EIRP is authorised in the 2.4 - 2.4835 GHz band for all other transmitters

In addition the LIPD class licence and associated Short Range Devices (SRD) standard include power spectral density limits that must be complied with.

Are there any equipment standards applying to WLAN devices?

There are currently two ACMA standards that are applicable to 2.4 GHz.

The spread spectrum standard has level 2 compliance requirements whereas the short range devices standard is level 1. The compliance level determines what information must be contained in an equipments compliance folder.

What is 802.11?

A group of related standards for WLAN equipment produced by the Institute of Electrical and Electronics Engineers (IEEE).

Different members of the IEEE 802.11 family have different characteristics, including radiofrequency spectrum characteristics, and operate in different frequency bands.

  • IEEE 802.11b covers devices operating in the 2.4 GHz band (2.4-2.4835 GHz) using spread spectrum modulation
  • IEEE 802.11g covers devices operating in the 2.4 GHz band (2.4-2.4835 GHz) using OFDM (orthogonal frequency division multiplex) modulation.
  • IEEE 802.11a covers WLANs that operate in the 5 GHz bands.

For more information:

What are the security risks of operating WLANs using IEEE 802.11 devices?

The IEEE 802.11a and b standards use a Wireless Equivalent Privacy (WEP) security protocol. It is an unsophisticated encryption method and WLAN operators should not rely on the in-built security measures of IEEE 802.11a and b.

What laws apply to the use of radiocommunications equipment?

Two laws cover different aspects of telecommunications services:

There are also licensing requirements.

What can you tell me about radiocommunications licensing?

Radiocommunications licensing relates to the use of the radiofrequency spectrum for communications purposes. There are three types of radiocommunications licences:

  • Apparatus licences authorise the operation of radiocommunications equipment for specific purposes, for example, land mobile, outpost, amateur, maritime or aeronautical communications and broadcasting. You pay a licence fee and the ACMA issues you with a licence to operate the equipment.
  • Class licences are open, standing authorities that allow anyone to operate particular radiocommunications equipment provided the operation and the device meet the conditions of the licence. Class licences do not have to be applied for and no licence fees are payable. Under class licensing, users may operate various types of radiocommunications equipment including citizen band radios, mobile and cordless phones and a range of other low power devices, such as remote control garage door openers.
  • Spectrum licences are a tradeable, technology neutral (that is, the licence is not related to any particular technology, system or service) spectrum access right for a fixed non-renewable term. Instead of authorising the use of a specific device, spectrum licences authorise the use of spectrum-space and give licensees the freedom to deploy any device from any site within their spectrum space, provided that use is compatible with the core conditions of the licence and the technical framework.

Is there any 'unlicensed spectrum' in Australia?

There is no unlicensed spectrum in Australia. Users must be licensed to operate radiocommunication transmitters.

How is access to the 2.4 GHz band managed?

The ACMA management approach to the 2.4 GHz band relies on a 'public park' concept.

Users of WLAN devices operating in this band are required to comply with a set of conditions:

  • No interference is to be caused to other radiocommunications users
  • No protection from interference is offered
  • There is no licence fee.

For more information:

In radiocommunications licensing, what does the 'public park' concept mean?

Under the 'public park' concept, all users are able to access a small portion of the total resource (the frequency band) and to share that resource in a way that requires minimal regulatory intervention.

The use of a 'public park' approach is administratively efficient and gives great freedom to users, but the price of this freedom is increased risk of interference.

Several ACMA class licences are associated with the'public park' concept to radiocommunications.

These licences include technical conditions promoting a high degree of sharing. Under such circumstances, use would typically be limited to relatively short-range operation.

What risks are there in operating in a 'public park'?

The risk of unplanned interference between uncoordinated users is always present. Interference risk is managed by the combination of class licence technical conditions and equipment design.

Possible risks including:

  • safety-of-life issues
  • loss of any core business information that might be carried on the WLAN network
  • the ability to guarantee a minimum quality of service

What about the use of WLANs in rural areas?

Compared to city use, the same diversity of uses for the 2.4 GHz band can be expected in rural towns but on a smaller scale and possibly at a lower overall density.

Is the 2.4 GHz 'public park' band suitable for public telecommunications applications?

Some parts of industry are using WLANs in the 2.4 GHz band to link into the public telecommunications network. This could involve point-to-point or wide-area communication. Where greater range is desired amplifiers and high gain antennas are used. This increases the risk of mutual interference between users operating in the 'public park'.

Given the uncoordinated nature of operations in the band and the risk of interference other devices it is not possible to guarantee a quality service for public telecommunications users.

What can you tell me about telecommunications licensing?

Under the Telecommunications Act 1997, there are two types of persons or organisations that can provide carriage services to the public:

  • Carriers
  • Carriage Service Providers (CSPs).

Carriers are defined as those persons who own a telecommunications network unit used to supply carriage services to the public. Carrier licences are granted by the ACMA under section 56 of the Telecommunications Act. Carriers must comply with carrier licensing obligations

Carriage Service Providers (CSPs) use a telecommunications network unit to supply carriage services to the public. CSPs are not required to obtain a licence from the ACMA to supply a carriage service to the public. CSPs must comply with service provider rules.

What about telecommunications licensing of WLAN equipment?

WLAN equipment may require a carrier licence. Whether a carrier licence is needed will depend on what the equipment is being used for and services supplied.

What constitutes supplying services in a single place - hotspots?

The operation of wireless equipment to supply carriage services to the public on a single premise (such as an Internet café, shopping centre, airport lounge, hotel or conference centre) does not require a carrier licence.

How do I know if I need a carrier licence?

You following questions would help determine if you need a licence:

  • Is there a network unit involved?
  • Is the network unit used 'to supply a carriage service to the public'?
  • Is the network unit exempt?

For more information see:

In general small businesses such as ISPs who meet the 'commercial' test would require a carrier licence.

Hobbyists and community users may not require a licence.

What are the conditions of a carrier licence?

Standard carrier licence conditions are found in Schedule 1 to the Telecommunications Act 1997.

A carrier must comply with the Telecommunications (Consumer Protection and Service Standards) Act 1999.

Carriers must comply with the following arrangements:

More information:

  • Know Your Obligations - Carriers, Carriage Service Providers, Internet Service Providers.

The ACMA does not provide legal advice. You are strongly advised to seek your own legal advice to clarify any issues of interpretation in relation to the matters raised above. The ACMA accepts absolutely no liability (including negligence) for any loss or damage suffered as a result of reliance on the accuracy of the information provided.

Last updated: 17 December 2012