Radiocommunications Advisory Guidelines (Protection of Apparatus-licensed Receivers 800 MHz Band) 1998 (Cth)
Commonwealth of
Radiocommunications Act 1992
Radiocommunications Advisory Guidelines (Protection of Apparatus-licensed Receivers - 800 MHz Band) 1998
THE AUSTRALIAN COMMUNICATIONS AUTHORITY makes the following guidelines under subsection 262 of the Radiocommunications Act 1992
Dated
A.J SHAW Chairman
R HORTON
Deputy Chairman
Australian Communications Authority
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CONTENTS
Clause
PART 1—INTRODUCTION
1.1 Title
1.2 Commencement
1.3 Purpose of these guidelines
1.4 Interpretation
PART 2—TRUNKED LAND-MOBILE SERVICES
2.1 Background
2.2 Trunked Land-Mobile Base Station Services
2.3, 2.4 Trunked Land-Mobile
PART 3—NARROWBAND FIXED POINT-TO-POINT SERVICE RECEIVERS
3.1 Background
3.2, 3.3 Protection requirements
PART 4—WIDEBAND FIXED POINT-TO-POINT SERVICE RECEIVERS
4.1 Background
4.2, 4.3, 4.4 Protection requirements
PART 5—STUDIO TRANSMITTER LINK RECEIVERS AND SOUND OUTSIDE BROADCAST LINK RECEIVERS
5.1, 5.2 Background
5.3 Protection requirements for studio to transmitter link receivers
5.4 Protection requirements for sound outside broadcast link
receivers
PART 6—GSM BASE STATION RECEIVERS
6.1, Background
6.2 Protection requirements
6.3, 6.4, 6.5 Additional information on GSM protection requirements
PART 7—AMPS BASE AND
7.1, 7.2, 7.3 Background
7.4 Protection for incumbent AMPS base and mobile receivers
7.5 Protection for continuing rural area AMPS base and mobile
receivers
SCHEDULE Propagation models
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BACKGROUND
The Minister has designated parts of the 800 MHz band for allocation by the issue of spectrum licences. Receivers of apparatus licensed services currently operate in those frequency bands and in adjacent frequency bands. These receivers may suffer interference from unwanted emissions, and from blocking and intermodulation, caused by a spectrum licensed transmitter. Unwanted emissions are by-products of a transmitter’s emissions and include broadband noise, harmonics, intermodulation products, transient signals and other spurious signals. Blocking occurs when a high level off-tune signal causes a degradation in the quality of the wanted output signal, produced by the overloading of the receiver’s front-end. Intermodulation products can be generated in the input stages of receivers in the presence of 2 or more high level signals at the receiver input.
These guidelines have been made for the management of this interference to apparatus licensed receivers operating in the following circumstances:
trunked land-mobile base receivers operating below 825 MHz and mobile receivers operating below 870 MHz
narrowband fixed point-to-point service receivers, operating in the 830 - 831 MHz and 875 - 876 MHz bands
wideband fixed point-to-point service receivers, operating in the 800 MHz spectrum licensed bands
studio transmitter link receivers and sound outside broadcast link receivers, operating above 845 MHz
GSM base station receivers, operating above 890 MHz
AMPS base and mobile receivers, operating in the 800 MHz spectrum licensed bands, and in adjacent area apparatus licensed bands.
As radio waves propagate in different ways because of factors such as frequency, terrain, atmospheric conditions and path length, there are a number of ways to predict path loss. Some suitable propagation models are set out in the Schedule.
PART 1 - INTRODUCTION
Title
1.1. These guidelines are called the Radiocommunications Advisory Guidelines (Protection of Apparatus-licensed Receivers - 800 MHz Band) 1998.
Commencement
1.2. These guidelines commence on
4 February 1998 .
Purpose of these guidelines
1.3. The purpose of these guidelines is to manage interference by providing for the protection of receivers of apparatus licensed services operating in or adjacent to the 800 MHz band:
outside the spectrum licensed bands; or
outside the spectrum licensed areas; or
at the time of designation, inside the spectrum space of spectrum designated for spectrum licensing.
The ACA will take these guidelines into account in determining whether a spectrum licensed transmitter is causing interference to an apparatus licensed receiver operating in any of the circumstances set out in these guidelines.
Interpretation
1.4. In these guidelines, unless the contrary intention appears:
designation, in relation to spectrum space, means designation by the Minister under section 36 of the Act for allocation by issuing spectrum licences.
GSM 05.05 means the European Telecommunications Standards Institute ETSI Specification ETS 300 577 - GSM 05.05 “Digital cellular Telecommunications System (Phase 2); Radio Transmission and Reception” as issued from time to time.
RALI LM 8 means the Radiocommunications Assignment and Licensing Instruction No. LM 8 issued by the ACA as in force from time to time, copies of which are available from the ACA.
RALI FX 11 means the Radiocommunications Assignment and Licensing Instruction No. FX 11 issued by the ACA as in force from time to time, copies of which are available from the ACA.
SMA means the Spectrum Management Agency.
SPP 2/97 means Spectrum Planning Report SPP 2/97 published in April 1998 by the SMA, titled ‘Compatibility Assessment - 800 MHz AMPS Spectrum Adjacent to GSM Spectrum’ copies of which are available from the ACA.
SPP 3/86 means Spectrum Planning Report SPP 3/86 version 1.1, published in March 1987 by the Department of Communications, titled 'Guidelines for the assignment of frequencies to two frequency, single channel fixed services in the 400 and 800 MHz bands', copies of which are available from the ACA.
SPP 5/93 means Spectrum Planning Report SPP 5/93, published in March 1993 by the SMA, titled 'Frequency assignment procedures for fixed service wideband links in the 820 - 960 MHz band', copies of which are available from the ACA.
Standard EIA/IS 19-B means the USA Electronic Industries Association Interim Standard IS-19-B, titled ‘Recommended Minimum Standards for 800 MHz Cellular Subscriber Units”, published in May 1988.
Standard EIA/IS 20-A means the USA Electronic Industries Association Interim Standard IS-20-A, titled ‘Recommended Minimum Standards for 800 MHz Cellular Land Stations”, published in May 1988.
s.145 determination means the Radiocommunications (Unacceptable Levels of Interference - 800 MHz Band) Determination 1998.
Unwanted signal means the by-products of a transmitter’s emission and includes modulation products, broadband noise, harmonic products, intermodulation products, transient signals and other spurious signals.
(2) A term used in these guidelines that is defined in the s.145 determination has the same meaning as in that determination.
[NOTES: 1. The following terms, used in this determination, are defined in the Radiocommunications Act 1992 and have the meanings given to them by that Act:
frequency band
interference
ACA
spectrum licence
transmitter.
2. The following terms are defined in the Radiocommunications (Unacceptable Levels of Interference - 800 MHz Band) Determination 1998 and have the meanings given to them by that Determination:
in-band
RadDEM
800 MHz band]
PART 2 - TRUNKED LAND-MOBILE RECEIVERS
Background
2.1 The 800 MHz trunked land-mobile service operates in a paired band. Base station receivers use the lower band, 820 - 825 MHz. Mobile receivers use the upper band, 865 - 870 MHz. Receivers in these two bands are in spectrum immediately adjacent to the 800 MHz spectrum licensing bands.
Trunked Land-Mobile Base Station Receivers
2.2 The protection requirements for base station receivers operating in the 820 - 825 MHz segment for the percentage of time specified in RALI LM 8 are:
a wanted to unwanted signal level ratio at the receiver input not less than the wanted to unwanted ratio specified in RALI LM 8; and
a blocking level at the receiver input not exceeding the blocking level specified in RALI LM 8; and
an unwanted signal level at the receiver input falling into any trunking channel in the above segment not exceeding the adjacent channel power requirement specified in RALI LM 8.
2.3 The RF selectivity performance of the base station receiver may be assumed to be at least equal to the performance of a cavity filter with a response as specified in RALI LM 8 tuned to the operating frequency of that receiver. The base station receiver I.F. bandwidth may be assumed to be that specified in RALI LM 8. The base station receiver antenna may be assumed to have a response equivalent to the notional antenna specified in RALI LM 8.
Trunked Land-Mobile
2.4 The protection requirements for mobile receivers operating in the 865 - 870 MHz segment for the percentage of time and percentage of locations specified in RALI LM 8 are:
a wanted to unwanted signal level ratio at the receiver input not less than the wanted to unwanted ratio specified in RALI LM 8;
a blocking level at the receiver input not exceeding the blocking level specified in RALI LM 8; and
an unwanted signal level at the receiver input falling into any trunking channel in the above segment not exceeding the adjacent channel power requirement specified in RALI LM 8.
The mobile receiver I.F. bandwidth may be assumed to be that specified in RALI LM 8.
PART 3 - NARROWBAND POINT-TO-POINT FIXED SERVICE RECEIVERS
Background
3.1 These 800 MHz single channel (25kHz), two frequency links operate in the bands 830-831 MHz and 875-876 MHz. In accordance with the 900 MHz Band Plan, no assignments have been made to this service since 1992. These incumbent services will require protection from the new services for a re-allocation period specified in the designation of the 800 MHz Band.
Protection requirements
3.2 The protection requirements for 800 MHz single channel, two frequency links are detailed in SPP 3/86. SPP 3/86 specifies a protection ratio of greater than or equal to 30 dB.
[NOTE: SPP 3/86 relates to a service subject to no further assignments, and is therefore not subject to ongoing regular review.]
PART 4 - WIDEBAND POINT-TO-POINT FIXED SERVICE RECEIVERS
Background
4.1 These 800 MHz wide band receivers operate in the bands 825-845 MHz and 870-890 MHz. These incumbent services will require protection from the new services for the re-allocation period specified in the designation of the 800 MHz Band. The majority of wide band links in the affected bands are of 2 MHz bandwidth supporting a mix of analogue and digital technologies. The reference bandwidth for these services is therefore set at 2 MHz. Assignments to this service have been normally restricted to systems required to relocate from other parts of the 900 MHz Band, in accordance with the 900 MHz Band Plan. The ACA does not propose to make further assignments to this service.
Protection requirements
4.2 The protection requirements for 800 MHz wide band links are detailed in Spectrum Planning Report SPP 5/93. The specified protection ratios in SPP 5/93 are:
co-channel: 50 dB
1 MHz separation: 45 dB
2 MHz separation: digital receiver 13 dB
analogue receiver 10 dB.
[NOTE: SPP 5/93 relates to a service subject to no further assignments, and is therefore not subject to ongoing regular review.]
PART 5 - STUDIO TRANSMITTER LINK RECEIVERS AND SOUND OUTSIDE BROADCAST LINK RECEIVERS
Background
5.1 Studio to transmitter links (STL) operate in the band 845 - 852 MHz, adjacent to the 800 MHz spectrum licensed lower band. Sound outside broadcast links (SOB) operations are also provided for in these bands, normally in the outer frequency segments 845 - 846.5 MHz and 850.5 - 852 MHz. STL and SOB are one way, single frequency fixed service links.
5.2 STLs vary in bandwidth from a typical 250 kHz for digital systems to between 60 and 400 kHz for analogue systems. RALI FX 11 specifies the maximum emission bandwidth for STLs as 400 kHz, in line with channelling arrangements in the 900 MHz Band Plan. SOBs typically utilise STL equipment on a temporary, transportable basis. SOBs operate on a no interference no protection basis.
Protection requirements for studio to transmitter link receivers
5.3 The protection requirements for studio to transmitter link receivers operating in the 800 MHz band are specified in RALI FX - 11.
Protection requirements for sound outside broadcast link receivers
5.4 RALI FX - 11 does not provide for any protection for sound outside broadcast link receivers (because of their temporary, transitory nature).
PART 6 - GSM BASE STATION RECEIVERS
Background
6.1 The GSM service operates in a paired band arrangement. Base station receivers use the lower band, 890 - 915 MHz, and base station transmitters use the upper band, 935 - 960MHz. Base station receivers are in spectrum immediately adjacent to the 870 - 890 MHz spectrum licensed band.
Protection requirements
6.2 The protection requirements for GSM base station receivers operating in the 890 - 915MHz segment for the percentage of time specified in SPP 2/97 are:
a wanted to unwanted signal level ratio not greater than the carrier to interference ratio (C/I) specified in SPP 2/97; and
a signal level not exceeding the blocking levels specified in GSM 05.05; and
the level of two signals, which have a frequency relationship such that a third-order intermodulation product falls within the IF bandwidth of the receive frequency of a GSM base receiver, not exceeding the receiver intermodulation level specified in GSM 05.05.
The reference point for all signal levels is the base station system (BSS) receiver antenna connector. The base station receiver I.F. bandwidth may be assumed to be that specified in SPP 2/97. The wanted signal level may be assumed to be never less than -106 dBm. Where multiple signals appear at the receiver antenna connector, an allowance for the summation of the power of multiple signals may be required to ensure that these requirements are met.
Additional information on GSM protection requirements
6.3 Analogue AMPS services have operated in the 870 - 890 MHz band since 1987. These services are now being phased out in accordance with government decisions, with final closure scheduled for
1 January 2000 , except possibly for some rural areas (see Part 7 for timetable). GSM services commenced operation in the adjacent band 890-900 MHz in 1995. This adjacent base transmit / base receive arrangement at 890 MHz is atypical; it is not usual spectrum management practice to allocate adjacent bands in such a way, due to mutual interference considerations. However, the current situation reflects past allocation arrangements put in place to implement government telecommunications competition objectives for the operation of AMPS and GSM. These frequency arrangements are set by regional standards making bodies, and thus are unavoidable if both technologies are to be utilised. To allow for optimum use of the spectrum in both these frequency segments, special technical and regulatory measures were put in place at the time.
6.4 Spectrum Planning Report SPP 2/97 examines the interference management framework put in place to address the compatibility requirements between analogue AMPS and GSM services. A feature of the framework is that filters were fitted at many sites to AMPS base transmitters and GSM base receivers, additional to those used in normal system configurations. This was necessary to minimise the likelihood of interference to GSM and thus optimise the use of these bands for both technologies. This requirement was critical at the actual frequency boundary (890 MHz), but was also implemented in other parts of the GSM bands, as necessary, by GSM licensees. In particular, filters have been fitted at most locations where AMPS and GSM are co-sited, and at other sites as necessary. The notional characteristics of the filters fitted at co-located sites are described in SPP 2/97. Specific location details and filter types can be obtained from the GSM operators.
6.5 It is likely that the 800 MHz band as it is recovered from analogue AMPS will be utilised for digital cellular base station transmitter operation under spectrum licensing arrangementsThe interference management approach described in SPP 2/97 for analogue AMPS / GSM will therefore be adaptable to the new situation. To optimise the future use of the spectrum licensed bands, and also to facilitate the ongoing deployment of GSM base stations, it will be necessary for special measures to be adopted in many instances. In particular, it is expected that licensees in both bands will find it difficult to deploy equipment without interference to adjacent band systems within several kilometres, unless additional high performance filtering is employed, in the same way as currently done for the AMPS / GSM solution. The fitting of high performance filters to both base transmitters and base receivers markedly improves the utility of both bands. The filters already in place on GSM receivers can assist in this regard. Negotiation between affected parties is seen as essential to optimising spectrum utility and access in the 890 MHz boundary situation.
PART 7 - AMPS BASE AND
Background
7.1 The 800 MHz spectrum subject to spectrum licensing (825-845/870-890 MHz) is currently used for the analogue AMPS services. It is being progressively withdrawn from that service, with allocation ceasing on
1 January 2000 . Some of this spectrum may be retained for analogue services in certain rural areas after that date. The timetable for the withdrawal of AMPS spectrum is:
| Stage # | Effective Date of Withdrawal | Amount of Spectrum (MHz) | Frequency Bands (MHz) |
| 1 | | 2 x 3 | 887-890/842-845 |
| 2 | | 2 x 2 | 885-887/840-842 |
| 3 | | 2 x 5 | 880-885/835-840 |
| 4 | | 2 x 5 | 870-875/825-830 |
| 5 | | 2 x 5 | 875-880/830-835 |
All frequency segments in the table are being spectrum licensed simultaneously, except for segment 5, which will initially only be available in major capital cities. Other areas are retained for possible ongoing AMPS use.
7.2 AMPS base and mobile receivers in spectrum licensed bands, as incumbent apparatus and class licensed devices, will be afforded ongoing protection from spectrum licensed services until the spectrum withdrawal date of each segment.
7.3 Analogue AMPS services that might continue in rural areas after
1 January 2000 would not constitute incumbent services, but apparatus licensees operating in adjacent areas or bands. These services will also require ongoing protection. The protection afforded however will need to take account of future government decisions about rural mobile services.
Protection requirements for incumbent AMPS base and mobile receivers.
7.4 Equipment in the analogue AMPS network operates in accordance with Standard EIA/IS 19-B and Standard EIA/IS 20-A. AMPS mobile stations are required to comply with AUSTEL Technical Standard TS005 which is based on EIA/IS 19-B.
7.5 The protection requirements for incumbent AMPS services are based on system planning criteria of a co-channel wanted to unwanted ratio of 18 dB for base and mobile receivers for 95% of the time and for mobiles in 95 % of locations. An IF bandwidth of 30 kHz and a wanted signal level never less than -113 dBm applies to these criteria.
Protection requirements for continuing rural area AMPS base and mobile receivers.
7.6 The protection requirements detailed in 7.4 and 7.5 apply to continuing rural area AMPS base and mobile receivers except that, at and near the frequency and geographic boundaries with 800 MHz spectrum licensed bands, AMPS services will not be afforded protection from emissions by spectrum licensed services that are allowed for in the S.145 Determination.
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SCHEDULE
PROPAGATION MODELS
Introduction
A number of propagation models have been developed to estimate the path loss between a transmitter and receiver. The choice of a particular propagation model will depend on a number of factors such as the terrain between the radio path end points, any obstructions on the path either natural or man-made, the heights of the transmit and receive antennas, and the limitations of applicability of the various propagation models.
ITU Recommendation P.1144 gives a guide on the applications of the various propagation methods developed internationally by the ITU. Table 1 is an extract of the 1995 issue of ITU Recommendation P.1144 and provides a summary of the ITU propagation models relevant to services operating in the 800 and 1800 MHz bands. The models provide an estimation of either path loss or received field strength.
Most models include statistical evaluation of path loss or signal levels expected at certain percentages of locations for certain percentages of times. Some propagation models produce a result that represents the median signal level. The median signal level corresponds to a level that is exceeded 50% of the time in 50% of locations. The median level is useful for estimating coverage. It is not suitable for interference calculations as interference for 50% of the time is generally considered unacceptable. Therefore, care must be taken when using propagation models to predict interference levels to ensure that the result represents the signal level exceeded for a sufficiently small percentage of locations for a sufficiently low percentage of time, as appropriate for the circumstance. Median signal levels may be converted to other time and location percentages (eg, 1% of the time and 10% of locations) by applying appropriate correction factors.
Propagation models
Propagation models can be classified into two different types; point-to-point and point-to-area.
Point-to-Point Models
Point-to-point models allow the prediction of path loss between a fixed transmitter and a fixed receiver. Two of the main propagation modes are:
free space loss (line-of-sight); and
diffraction loss including smooth earth diffraction and diffraction over obstacles and irregular terrain (knife-edge diffraction).
The free space loss propagation model is usually used where paths are line-of-sight and there are no obstructions within the first Fresnel zone for a given k-factor. This usually occurs with services located on high sites such as mountain tops, towers or buildings.
The diffraction loss propagation model is typically used where paths are obstructed by the earth’s curvature or terrain. The model gives a loss due to diffraction which must be added to the free space loss to give the total path loss.
A plot of the terrain profile is usually generated to determine which propagation model is most appropriate to a particular propagation path.
Information on how to determine propagation losses due to free space and diffraction over a spherical earth, obstacles and irregular terrain can be found in ITU-R Recommendation P.526. Additional propagation loss due to effects such as tropospheric scatter, ducting, layer reflections and clutter can be found in ITU-R Recommendation P.452. The ITU has available a computer program to predict propagation loss in accordance with ITU-R Recommendation P.452.
Point-to-Area Models
Point-to-area models provide for the prediction of field strength levels in a geographic area from a base station transmitter. They are useful for estimating the coverage area of base stations in which receivers are to be protected from interference and to estimate interference to mobile receivers from other services. They are statistical in nature and usually based on the statistical analysis of measured data and take into account factors such as
ITU-R Recommendation P.529 provides guidance on the prediction of field strength for the land mobile service in the VHF and UHF bands. It contains curves for predicting median field strengths for 50% of locations for 50% of the time under average conditions. It also provides various correction factors which can be used to refine the average predictions to take account of the terrain. The curves are based on measurements made by Okamura and Hata in
Other point-to-area models such as those developed by Hata (Okumura) or Longley-Rice may also be appropriate as they include factors for clutter (buildings, trees etc) with low receive antenna heights. The Hata model also makes allowance for the difference in path losses between urban, suburban and rural areas. The Hata model was derived from experiments measuring signal levels of land mobile services in
It should be noted that there are significant restrictions in the range of applicability of the Hata model as it:
is limited to propagation paths up to 20 km in length; and
is limited in the range of valid antenna heights: the low antenna must be in the range 1 to 10 m; and the high antenna must be in the range 30 to 200 m. It should be noted that the Hata model does not take into account specific path variations, so the antenna heights used should be the effective height above the surrounding terrain and not solely the antenna height above ground level.
The Modified Hata model (ITU-R Report 567-4) extends the path length range to 100 km.
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TABLE 1
ITU-R Propagation Prediction Methods for the 800 and 1800 MHz Frequency Bands
| Method | Application | Type | Output | Frequency | Distance | % time | % location | Terminal height | Input data |
| Rec. ITU-R P.370 | Broadcasting | Point-to-area | Field strength | 30 MHz to 1000 MHz | 10 to 1 000 km | 1, 5, 10, 50 | 1 to 99 | Tx: effective height from less than 0 m to greater than 1 200 m | Distance |
| Rec. ITU-R P.452 | Services employing stations on | Point-to-point | Path loss | 700 MHz to 30 GHz | Not specified but up to and beyond the radio horizon | 0.001 to 50 | Not applicable | No limits specified | Path profile data |
| Rec. ITU-R P.526 | Fixed | Point-to-point | Field Strength | Not specified but generally >30 MHz | Not specified but up to and beyond the radio horizon | Not specified but dependent on k-factor chosen | Not applicable | No limits specified | Path profile data |
| Rec. ITU-R P.528 | Aeronautical | Point-to-area | Path loss | 125 MHz to 15 GHz | 0 to 1 800 km (For aeronautical applications 0 km horizontal distance does not mean 0 km path length) | 5, 50, 95 | Not applicable | H1: 15 m to 20 km | Distance |
| Rec. ITU-R P.529 | Land mobile | Point-to-area | Field strength | 30 MHz to 3 GHz (Limited application above 1.5 GHz) | VHF: 10 to | VHF: 1, 10, 50 | Unspecified | Base: 20 m to 1 km | Distance |
| Rec. ITU-R P.530 | Line-of-sight Fixed links | Point-to-point Line-of-sight | Path loss | Approximately | Up to 200 km | All percentages of time in clear-air conditions; | Not applicable | High enough to ensure specified path clearance | Distance |
| Rec. ITU-R P.617 | Trans-horizon fixed links | Point-to-point | Path loss | >30 MHz | 100 to 1 000 km | 20, 50, 90, 99, | Not applicable | No limits specified | Frequency |
| Rec. ITU-R P.618 | Fixed satellite | Point-to-point | Path loss. | 1 to 30 GHz | Any practical orbit height | 0.001, 0.01, 0.1, and 1 (for both rain attenuation and XPD) (1) | Not applicable | No limit | Meteorological data |
| Rec. ITU-R P.620 | Earth station frequency coordination | Coordination distance | Distance of which the required propagation loss is achieved | 1 to 40 GHz | 100 to 1 200 km | 0.001 to 1 | Not applicable | No limits specified | Frequency |
| Rec. ITU-R P.681 | Land mobile satellite | Point-to-point | Path fading | 0.8 to 3 GHz | Any practical orbit height | Not applicable | Not applicable | No limit | Frequency |
| Rec. ITU-R P.1146 | Land mobile Broadcasting | Point-to-area | Field strength | 1 to 3 GHz | 1 to 500 km | 1 to 99 | 1 to 99 | Tx: =>= 1 m | Distance |
0
0
0