Radiocommunications Advisory Guidelines (Managing Interference to Spectrum Licensed Receivers – 1800 MHz Band) 2012

Radiocommunications Act 1992

The AUSTRALIAN COMMUNICATIONS AND MEDIA AUTHORITY makes these Advisory Guidelines under section 262 of the Radiocommunications Act 1992.

Dated 26 September 2012

Chris Chapman
[signed]
Member

 

 

Brendan Byrne
[signed]
Member/General Manager

 

Australian Communications and Media Authority


1 Name of Advisory Guidelines

 These Advisory Guidelines are the Radiocommunications Advisory Guidelines (Managing Interference to Spectrum Licensed Receivers - 1800 MHz Band) 2012.

2 Commencement

These guidelines commence on 18 June 2013.

Note All legislative instruments and compilations are registered on the Federal Register of Legislative Instruments kept under the Legislative Instruments Act 2003. See http://www.frli.gov.au.

3 Revocation

 The Radiocommunications Advisory Guidelines (Managing Interference from Apparatus-licensed and Class-licensed Transmitters – 1800 MHz band) 1999 are revoked.

4 Purpose of these Advisory Guidelines

(1) The purpose of these guidelines is to:

(a) manage in-band and out-of-band interference by providing compatibility requirements for registered fixed receivers operating under spectrum licences issued for the 1800 MHz band; and

(b) provide protection to radiocommunications receivers operating under spectrum licences issued for the 1800 MHz band from interference caused by radiocommunications transmitters operating under a class licence, and from fixed transmitters operating under:

(i) an apparatus licence issued on or after the 18 June 2013; or

(ii) a spectrum licence where the transmitter is registered under Part 3.5 of the Act on or after 18 June 2013.

 

(2) These guidelines should be used by operators of spectrum licensed services and apparatus licensed services in the planning of services or in the resolution of an interference case.

5 Interpretation

(1) In these guidelines, unless the contrary intention appears:

 

1800 MHz band means the frequency bands:

 (a) 1710 MHz - 1785 MHz (the 1800 MHz Lower band); and

(b) 1805 MHz - 1880 MHz (the 1800 MHz Upper band).

 

Act means the Radiocommunications Act 1992.

 

adjacent channel means a channel with a centre frequency offset on either side of the assigned channel frequency of the occupied channel by a specific frequency relation. 

 

adjacent channel selectivity means a measure of the ability of the radiocommunications receiver to receive a wanted signal without exceeding a specified degradation in output quality due to the presence of an unwanted adjacent channel signal.

 

blocking means a measure of the ability of a radiocommunications receiver to receive a wanted signal in the presence of a high level unwanted interferer on frequencies other than those of the adjacent channels.

 

emission buffer zone means a zone along the frequency or geographic boundary of a spectrum licence where emission levels of radiocommunications transmitters are reduced to ensure that significant levels of emissions stay within the geographic area and frequency band of the licence.

 

in-band means:

(a)     for a radiocommunications transmitter or radiocommunications receiver operated under a spectrum licence, the frequencies within the frequency band in which operation of those radiocommunications devices is authorised under the licence; and

(b)     for a radiocommunications transmitter or radiocommunications receiver operating under an apparatus licence, the frequencies within the lower frequency limit and the upper frequency limit specified in the licence.

 

intermodulation response rejection means a measure of the ability of a radiocommunications receiver to receive a wanted signal in the presence of two or more unwanted signals with a specific amplitude and frequency relationship to the wanted signal frequency.

 

out-of-band means:

(a)   for a radiocommunications transmitter or radiocommunications receiver operated under a spectrum licence, the frequencies outside the frequency band in which operation of those radiocommunications devices is authorised under the licence; and

(b)   for a radiocommunications transmitter or radiocommunications receiver operating under an apparatus licence, the frequencies outside the lower frequency limit and upper frequency limit specified in the licence.

 

section 145 Determination means the Radiocommunications (Unacceptable Levels of Interference - 1800 MHz Band) Determination 2012.

 

spectrum space means a 3 dimensional space consisting of a frequency band and a geographic area.


spurious response immunity means a measure of the ability of a radiocommunications receiver to discriminate between the wanted signal and an unwanted signal at any frequency, outside the frequency band of the licence, to which the receiver responds.

 

unwanted signal means all emissions from any radiocommunications transmitter which is not communicating with the radiocommunications receiver of a service protected by these guidelines.

 

wanted signal means the radiofrequency emission from a radiocommunications transmitter designed for communication between the transmitter and the radiocommunications receiver of a service protected by these guidelines.

 

(2) Unless the contrary intention appears, terms used in these guidelines that are defined in the section 145 Determination have the same meaning as in that determination.

 

Note 1 The following terms that are used in these guidelines are defined in the section 145 Determination:

 

-  centre frequency

-  device boundary

-  device boundary criterion

-  effective antenna height

-  fixed receiver

-  fixed transmitter

-  geographic area

-  mobile transmitter

 

Note 2 A number of terms used in these guidelines are defined in the Act and unless the contrary intention appears, have the meanings given to them by the Act including:

 

- ACMA

- apparatus licence

- class licence

- core condition

- frequency band

- interference

- radiocommunications receiver

- radiocommunications transmitter

- Register

- spectrum licence

 

 

 


Part 1 Background

A spectrum licence consists of a frequency band and a geographic area.  Interference occurring between adjacent spectrum licences consists of:

This interference is managed by creating emission buffer zones along the geographic and frequency boundaries of the licence, using a number of provisions of the Act.  These include:

The following guidelines have been made to provide guidance on the management and settlement of interference to radiocommunications receivers operating under spectrum licences in the 1800 MHz band and caused by radiocommunications transmitters operating under any other licence issued under the Act.

 

 


Part 2 Managing interference from other services

 

2.1 In-band interference

(1) In-band interference caused in a radiocommunications receiver operating under a spectrum licence in the 1800 MHz band by a radiocommunications transmitter operating under an adjacent spectrum licence is managed by the core conditions imposed on the spectrum licences under section 66 of the Act, the device boundary criteria and deployment constraints prescribed in the section 145 Determination and the additional device boundary criteria defined in the Radiocommunications Advisory Guidelines (Additional Device Boundary Criteria – 1800 MHz Lower band) 2012.

 

(2) In-band interference caused in a radiocommunications receiver operating under a spectrum licence in the 1800 MHz band by a radiocommunications transmitter operating under an apparatus licence that is issued on or after 18 June 2013, is managed as if the transmitter is operated under a spectrum licence. The same device boundary criteria, as applied to spectrum licensed radiocommunications transmitters are also applied to new apparatus licensed radiocommunications transmitters.  Therefore, spectrum licensed receivers are afforded the same level of in-band protection from new apparatus licensed radiocommunications transmitters as they are afforded from radiocommunications transmitters operated under adjacent spectrum licences.

Note These guidelines do not cover interference caused by radiocommunications transmitters operating under apparatus licences that were issued before 18 June 2013. Spectrum licensees should accept any interference caused by such transmitters.

 

(3) Application of the device boundary criteria manages in-band interference and these criteria incorporate emission limits that provide reasonable protection throughout the total geographic area of a licence.  Emission limits are also used to manage out-of-band interference but these do not provide protection along the frequency boundaries of a spectrum licence throughout the entire geographic area. Because of the nature of out-of-band interference, emission limits cannot be used to provide protection from out-of-band interference for devices that are located near each other, for example, at multi-operator sites.

 

(4) The ACMA will not regard in-band interference to a radiocommunications receiver operating under a spectrum licence caused by a radiocommunications transmitter operating under a class licence as unacceptable if the operation of the transmitter complies with all relevant conditions of the class licence.


2.2 Out-of-band interference

 

(1) Out-of-band interference is difficult to predict because the levels and frequencies of 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 MHz 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’s 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 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.

 

2.3                        Recording radiocommunications receiver details in the Register

 

(1)     In these guidelines, for a radiocommunications receiver operated under a spectrum licence to be afforded protection from interference caused by an apparatus licensed radiocommunications transmitter, the details of the receiver must be on the Register before the date of issue of the apparatus licence under which the transmitter operates.

(2)     In these guidelines, for a radiocommunications receiver operated under a spectrum licence to be afforded protection from interference caused by a spectrum licensed radiocommunications transmitter, the details of the receiver must be on the Register before the details of the transmitter are placed on the Register.

Note See Part 4 (Compatibility Requirement).

 

2.4 Mobile and nomadic devices

 

The compatibility requirement (specified in Part 4) does not apply to mobile or nomadic devices because the transient nature of these devices prevents the use of this requirement as an interference management procedure.  Mobile and nomadic radiocommunications receivers have by their nature the ability to avoid an interference source unlike a fixed receiver.

 


Part 3 Minimum level of receiver performance

 

3.1 Notional receiver performance

(1) The level of interference caused by out-of-band emissions depends on the interference susceptibility of a radiocommunications receiver.  Emission levels from radiocommunications transmitters should not have to be reduced below a point where the performance of the radiocommunications receiver is really the problem. 

(2) Therefore, it is necessary to establish a benchmark notional (minimum) receiver performance level for the radiocommunications receiver when setting a compatibility requirement for radiocommunications receivers. The recommended notional receiver performance level is set out in Schedule 1. A receiver must meet the notional level of performance to gain protection from interference from radiocommunications transmitters under these guidelines. 

Note Schedule 1 specifies the receiver performance level based on information available to the ACMA at the time of making these guidelines. The notional receiver performance level may be amended in the future.  Any amendments to these guidelines would be made following consultation with 1800 MHz band spectrum licensees.

 

 

 


Part 4 Compatibility requirement

 

4.1 Compatibility

(1)          The licensee of a fixed transmitter operating under an apparatus licence or a spectrum licence must ensure that the transmitter meets the compatibility requirements in Schedule 2, in relation to a fixed receiver, if the receiver:

(a) has the notional level of performance set out in Schedule 1;

(b) was registered in the Register before:

(i) the transmitter is registered (if the transmitter is operated under a spectrum licence); or

(ii) the date of issue of the apparatus licence under which the transmitter operates; and

(c) operates under a spectrum licence:

(i) in the 1800 MHz Lower band; or

(ii) in the 1800 MHz Upper band with an effective antenna height for each increment 1, he1(n) less than, or equal to 10 metres.

(2)          For subparagraph 4.1 (1) (c) (ii), the effective antenna height (he1(n)) for a radiocommunications receiver is calculated in accordance with Schedule 3 of the section 145 Determination as if the receiver were a transmitter.

 

 Note The 10 metre effective antenna height limit for the 1800 MHz Upper band is chosen to be consistent with common deployment practice.

 

(3)          A radiocommunications transmitter operating under a class licence must comply with the conditions of the class licence.


Schedule 1 Notional receiver performance level

  (section 3.1)

 

(1) This notional level of performance for a radiocommunications receiver operating under a spectrum licence issued for the 1800 MHz band relates to:

(a) adjacent channel selectivity;

(b) intermodulation response rejection;

(c) receiver blocking; and

(d) spurious response immunity.

 

(2) These performance parameters of the radiocommunications receiver are defined at the antenna connector port of the receiver unit. All frequency offsets are specified with reference to the upper and lower limits of the frequency bands of the spectrum licence under which the receiver operates.

 

(3) Adjacent channel selectivity

The adjacent channel selectivity requirement is expressed as a ratio between the unwanted signal and the compatibility requirement specified in Schedule 2. The minimum notional adjacent channel selectivity shall be greater than or equal to 43.5 dB with a frequency offset of less than 5 MHz from the frequency limit of the licence under which the radiocommunications receiver operates.

 

(4) Intermodulation response rejection

The minimum notional radiocommunications receiver intermodulation rejection level is -74 dBm per 30 kHz at an offset greater than or equal to 5 MHz from the frequency limit of the licence under which the receiver operates.

 

The intermodulation response rejection requirement is expressed as a maximum power level of an individual unwanted signal when in the presence of another signal of equal or greater power level and with a frequency relationship that may result in a third order or higher intermodulation product on the operating frequency of the spectrum licensed receiver.

 

(5) Receiver blocking

The minimum notional blocking requirement, expressed as tolerance to a minimum unwanted signal level is:

(a) -65 dBm per 30 kHz at frequency offsets greater than 5 MHz from the frequency limit of the licence and within the band 1690-1805 MHz; and

(b) a total mean power of -15 dBm for frequencies outside the band 1690-1805 MHz.

(6) Spurious response immunity

The spurious response immunity, expressed as a ratio between the unwanted signal and the compatibility requirement specified in Schedule 2, is 65 dB.

 

(7) External radiofrequency (RF) selectivity

External RF selectivity is the combination of any form of filtering that occurs between the radiocommunications receiver antenna and the input of the receiver. The notional level of external RF selectivity (between the antenna and the antenna connector of the receiver) may be assumed to be at least equal to:

(a)  dB for FreqOffset ≤ 20.5 MHz; and

(b) 70 dB for FreqOffset > 20.5 MHz

where “FreqOffset” is the smallest frequency difference between either the upper or lower limits of the frequency band of the spectrum licence under which the receiver operates and any frequency outside the frequency band.

 

(8) Receiver antenna and feeder losses

The antenna gain and feeder loss recorded for the radiocommunications receiver on the Register should be used for coordination. If an antenna gain or feeder loss is not available in the Register, then the following values shall be used:

(a) antenna gain of 18 dBi in all directions; and

(b) feeder loss of 2 dB.

 

 


Schedule 2 Compatibility requirement

  (section 4.1)

 

(1)                    The compatibility requirement for a fixed receiver, operating under a spectrum licence, to be provided by a radiocommunications transmitter operating under an apparatus or spectrum licence, is a maximum unwanted signal level, at the antenna connector port of the receiver, that is never more than -123.5 dBm for more than 1% of the time in any 1 hour period when measured within a 30 kHz rectangular bandwidth that is within the frequency band of the spectrum licence.

 

(2)                    Logarithmic scaling should be used to find the appropriate level in alternative bandwidths.