{"id":"F2023L00245","name":"Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2023","slug":"radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":103874,"registerId":"commonwealth-F2023L00245-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"Name","content":"#### 1 Name\n\n This is the Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2023.","sortOrder":0},{"sectionNumber":"3","sectionType":"section","heading":"Authority","content":"#### 3 Authority\n\n This instrument is made under subsection 145(4) of the Act.","sortOrder":1},{"sectionNumber":"5","sectionType":"section","heading":"Definitions","content":"#### 5 Definitions\n\n (1) In this instrument, unless the contrary intention appears:\n\n> 1800 MHz band means the 1800 MHz lower band and the 1800 MHz upper band.\n\n> 1800 MHz lower band means the frequency band 1710 MHz to 1785 MHz.\n\n> 1800 MHz spectrum licence means a spectrum licence that authorises the operation of radiocommunications devices in the 1800 MHz band.\n\n> 1800 MHz upper band means the frequency band 1805 MHz to 1880 MHz.\n\n> AAS means a base station antenna system where the amplitude and/or phase between antenna elements is continually adjusted, resulting in an antenna pattern that varies in response to short term changes in the radio environment.\n\n> Note: AAS stands for active antenna system.\n\n> Act means the Radiocommunications Act 1992.\n\n> additional device boundary: see item 4 of Schedule 2.\n\n> additional device boundary criterion: see item 5 of Schedule 2.\n\n> areas of high mobile use: see Schedule 4.\n\n> Australian Spectrum Map Grid means the Australian Spectrum Map Grid 2012, published by the ACMA.\n\n> Note: The Australian Spectrum Map Grid is available, free of charge, from the ACMA’s website at www.acma.gov.au.\n\n> Australian territorial sea baseline means the baseline from which the breadth of the territorial sea, or any part of the territorial sea, is to be measured under section 7 of the Seas and Submerged Lands Act 1973.\n\n> centre frequency, in relation to a radiocommunications transmitter, means the frequency midway between the lower and upper frequency limits of the transmitter’s occupied bandwidth.\n\n> DEM-3S means the dataset:\n\n (a) with the citation “Gallant, J., Wilson, N., Tickle, P.K., Dowling, T., Read, A. 2009. 3 Second SRTM Derived Digital Elevation Model (DEM) Version 1.0. Record 1.0. Geoscience Australia, Canberra”; and\n (b) given the persistent identifier http://pid.geoscience.gov.au/dataset/ga/69888;\n published by Geoscience Australia.\n\n> Note: DEM-3S is available, free of charge, from Geoscience Australia using the persistent identifier. More information about DEM-3S is available, free of charge, from the Geoscience Australia website at www.ga.gov.au.\n\n> DEM-3S cell means an individual height element of the DEM-3S.\n\n> device boundary: see item 1 of Schedule 2.\n\n> device boundary criterion: see item 2 of Schedule 2.\n\n> effective antenna height: see Schedule 3.\n\n> EIRP, in relation to a radiocommunications device, means the equivalent isotropically radiated power of the device.\n\n> emission designator: see section 7.\n\n> fixed receiver means a radiocommunications receiver:\n\n (a) located at a fixed point on land or sea; and\n (b) not designed or intended for use while in motion.\n\n> fixed transmitter means a radiocommunications transmitter:\n\n (a) located at a fixed point on land or sea; and\n (b) not designed or intended for use while in motion.\n\n> GDA94 means the geodetic datum designated as the “Geocentric Datum of Australia (GDA)”, gazetted in the Commonwealth of Australia Gazette No. GN 35 on 6 September 1995, as existing on that date.\n\n> Note: Gazette No. GN 35 is available, free of charge, from the Federal Register of Legislation at www.legislation.gov.au.\n\n> geographic area, for a spectrum licence, means the area within which operation of a radiocommunications device is authorised under the licence.\n\n> group of radiocommunications receivers: see section 9.\n\n> group of radiocommunications transmitters: see section 8.\n\n> HCIS means the cell grouping hierarchy scheme used to describe areas in the Australian Spectrum Map Grid.\n\n> Note: HCIS stands for hierarchical cell identification scheme.\n\n> HCIS identifier means an identifier used to describe an area in the HCIS.\n\n> high sited: see subsection (2).\n\n> horizontally radiated power, for a radiocommunications device, means the sum of:\n\n (a) the maximum true mean power, in dBm per specified rectangular bandwidth, at the antenna connector, that is located within the frequency band of the spectrum licence authorising the operation of the radiocommunications device; and\n (b) the antenna gain relative to an isotropic antenna in a specified direction in the horizontal plane containing the phase centre of the antenna used with the radiocommunications device, in dBi.\n\n> ITU-R Recommendation means a recommendation made by the Radiocommunication Sector of the International Telecommunication Union.\n\n> Note: ITU-R Recommendations are available, free of charge, from the website of the International Telecommunication Union at www.itu.int.\n\n> location: see Schedule 1.\n\n> low sited: see subsection (3).\n\n> maximum true mean power means the true mean power measured in a specified rectangular bandwidth that is located within a specified frequency band, such that the true mean power is the maximum of the true mean powers produced.\n\n> Note: The power within the specified rectangular bandwidth is normally established by taking measurements using either an adjacent channel power meter or a spectrum analyser. Estimation of the accuracy of the measuring equipment, the measurement protocol and any adjustments made to measurements to take account of practical filter shape factors should be in accordance with good engineering practice.\n\n> mean power means the average power measured during an interval of time that is at least 10 times the period of the lowest modulation frequency.\n\n> occupied bandwidth, in relation to a radiocommunications transmitter, means the width of a frequency band having upper and lower limits that contain 99% of the true mean power of the transmitter’s emission at any time.\n\n> Radio Regulations means the document titled ‘Radio Regulations’, published by the International Telecommunication Union.\n\n> Note 1: The Radio Regulations are not regulations made by the Governor-General under the Act.\n\n> Note 2: The Radio Regulations are available, free of charge, from the International Telecommunication Union’s website at www.itu.int.\n\n> true mean power means:\n\n (a) if an unmodulated carrier is present – the mean power measured while the unmodulated carrier is present; or\n (b) if an unmodulated carrier is not present – the mean power measured while transmitted information is present.\n\n> Note: A number of other expressions used in this instrument are defined in the Act, including the following:\n\n (a) ACMA;\n (b) core condition;\n (c) frequency band;\n (d) interference;\n (e) radiocommunications device;\n (f) radiocommunications receiver;\n (g) radiocommunications transmitter;\n (h) radio emission;\n (i) Register;\n (j) spectrum licence.\n (2) A radiocommunications device is high sited if its effective antenna height for any increment 1, ![](image.002.png) is greater than 10 metres.\n (3) A radiocommunications device is low sited if it is not high sited.\n (4) In this instrument, unless otherwise specified, a reference to a part of the spectrum or a frequency band includes all frequencies that are greater than but not including the lower frequency, up to and including the higher frequency.\n\n> Note: This subsection means the lower number in a part of the spectrum or a frequency band is not included in the frequency band.","sortOrder":2},{"sectionNumber":"6","sectionType":"section","heading":"References to other instruments","content":"#### 6 References to other instruments\n\n In this instrument, unless the contrary intention appears:\n (a) a reference to any other legislative instrument is a reference to that other legislative instrument as in force from time to time; and\n (b) a reference to any other kind of instrument or writing is a reference to that other instrument or writing as in force or existence from time to time.\n\n> Note 1: For references to Commonwealth Acts, see section 10 of the Acts Interpretation Act 1901; and see also subsection 13(1) of the Legislation Act 2003 for the application of the Acts Interpretation Act 1901 to legislative instruments.\n\n> Note 2: All Commonwealth Acts and legislative instruments are registered on the Federal Register of Legislation.\n\n> Note 3: See section 314A of the Act.","sortOrder":3},{"sectionNumber":"7","sectionType":"section","heading":"Emission designator","content":"#### 7 Emission designator\n\n (1) For the purpose of this instrument, the designation of a radiocommunications transmitter’s emission (emission designator) is determined using the methods specified in the Radio Regulations.\n (2) For the purpose of determining the emission designator of a radiocommunications transmitter using the methods specified in the Radio Regulations, references in the Radio Regulations to “necessary bandwidth” for a given class of emission are taken to be references to the occupied bandwidth of the transmitter.\n\n> Note: At the time the ACMA made this instrument, Appendix 1 of the Radio Regulations set out the method to be used for determining the designation of a radiocommunications transmitter’s emission.","sortOrder":4},{"sectionNumber":"8","sectionType":"section","heading":"Group of radiocommunications transmitters","content":"#### 8 Group of radiocommunications transmitters\n\n (1) For the purposes of this instrument, and subject to subsection (2), two or more fixed transmitters are a group of radiocommunications transmitters if:\n (a) each transmitter has the same centre frequency and emission designator; and\n (b) each transmitter is operated for the purpose of communicating with the same radiocommunications receiver or group of radiocommunications receivers; and\n (c) each transmitter has an antenna of the same type, model and manufacture; and\n (d) the antenna used with each transmitter is located on the same structure and within 20 metres of the phase centre of all antennas for the other transmitters within the group of radiocommunications transmitters; and\n (e) the identification number assigned by the ACMA to the antenna used with each radiocommunications transmitter is the same.\n\n> Note: See section 144 of the Act, and any instrument made under that section, for the information that must be included in the Register about a spectrum licence and each radiocommunications device operated under a spectrum licence.\n\n (2) A radiocommunications transmitter must not belong to more than one group of radiocommunications transmitters.\n\n> Note: If a radiocommunications transmitter is capable of belonging to more than one group of radiocommunications transmitters, the spectrum licensee or authorised third party may nominate one group for the transmitter.","sortOrder":5},{"sectionNumber":"9","sectionType":"section","heading":"Group of radiocommunications receivers","content":"#### 9 Group of radiocommunications receivers\n\n (1) For the purposes of this instrument, and subject to subsection (2), two or more fixed receivers are a group of radiocommunications receivers if:\n (a) each receiver is operated for the purpose of communicating with the same radiocommunications transmitter or group of radiocommunications transmitters; and\n (b) each receiver has an antenna of the same type, model and manufacture; and\n (c) the antenna used with each receiver is located on the same structure and within 20 metres of the phase centre of all antennas for the other receivers within the group of radiocommunications receivers; and\n (d) the identification number assigned by the ACMA to the antenna used with each radiocommunications receiver is the same.\n\n> Note: See section 144 of the Act, and any instrument made under that section, for the information that must be included in the Register about a spectrum licence and each radiocommunications device operated under a spectrum licence.\n\n (2) A radiocommunications receiver must not belong to more than one group of radiocommunications receivers.\n\n> Note: If a radiocommunications receiver is capable of belonging to more than one group of radiocommunications receivers, the spectrum licensee or authorised third party may nominate one group for the receiver.","sortOrder":6},{"sectionNumber":"10","sectionType":"section","heading":"Unacceptable level of interference","content":"#### 10 Unacceptable level of interference\n\n (1) A level of interference caused by a radiocommunications transmitter operated under an 1800 MHz spectrum licence is unacceptable if:\n (a) the operation of the transmitter results in a contravention of a core condition of the licence relating to the maximum permitted level of radio emission from the transmitter:\n (i) outside the parts of the spectrum the use of which is authorised under the licence; or\n (ii) outside the geographic area of the licence; or\n (b) subject to subsection (2), any part of the device boundary of the transmitter lies outside of the geographic area of the licence; or\n (c) the device boundary of the transmitter cannot be calculated in accordance with item 1 of Schedule 2; or\n (d) the transmitter:\n (i) operates in the 1800 MHz lower band; and\n (ii) is high sited; and\n (iii) operates within an area of high mobile use specified in Schedule 4; or\n (e) the transmitter:\n (i) operates in the 1800 MHz lower band; and\n (ii) is high sited; and\n (iii) has an occupied bandwidth with lower or upper frequency limits that are less than 10 MHz from a frequency adjacent spectrum licence with a geographic area that includes the location of the transmitter; or\n (f) subject to subsection (3), any part of the additional device boundary of the transmitter lies outside of the geographic area of the licence, and the transmitter:\n (i) operates in the 1800 MHz lower band; and\n (ii) is high sited; and\n (iii) operates outside an area of high mobile use specified in Schedule 4.\n (2) A level of interference mentioned in paragraph (1)(b) is not unacceptable in relation to a part of the device boundary of the transmitter that:\n (a) lies outside the geographic area of the licence; and\n (b) is connected to a radial that:\n (i) is mentioned in item 1 of Schedule 2; and\n (ii) does not cross over land outside the geographic area of the licence that is permanently above the Australian territorial sea baseline.\n (3) A level of interference mentioned in paragraph (1)(f) is not unacceptable in relation to a part of the additional device boundary of the transmitter if:\n (a) the additional device boundary of the transmitter is wholly within the geographic area of one or more spectrum licences, other than the licence under which the transmitter operates (the other spectrum licences); and\n (b) the occupied bandwidth of the transmitter is wholly or partly within the frequency band within which the operation of radiocommunications devices is authorised under each of the other spectrum licences; and\n (c) the licensee of the spectrum licence under which the transmitter operates either:\n (i) is the licensee of each of the other spectrum licences; or\n (ii) has the written agreement of the licensee of each of the other spectrum licences to exceed the additional device boundary criterion for the transmitter.\n (4) This section does not apply in relation to a radiocommunications transmitter to which section 12 applies.\n\n> Note Subsection 145(1) of the Act provides that the ACMA may refuse to include in the Register details of a radiocommunications transmitter if the ACMA is satisfied that operation of the transmitter could cause an unacceptable level of interference to the operation of other radiocommunications devices. However, some radiocommunications transmitters are exempt from the requirement to be registered in the Register under their 1800 MHz band spectrum licence – see subsection 69(2) of the Act.","sortOrder":7},{"sectionNumber":"11","sectionType":"section","heading":"Accuracy","content":"#### 11 Accuracy\n\n Unless otherwise specified, the value of a parameter in Schedule 2 and 3 must be estimated with a level of confidence not less than 95 percent that the true value of the parameter will always remain below the requirement specified in this instrument.","sortOrder":8},{"sectionNumber":"12","sectionType":"section","heading":"Transitional — radiocommunications transmitter registered before commencement of this instrument","content":"#### 12 Transitional – radiocommunications transmitter registered before commencement of this instrument\n\n (1) If a radiocommunications transmitter was included in the Register in relation to an 1800 MHz band spectrum licence before the commencement of this instrument (relevant transmitter), this section applies in relation to that transmitter.\n (2) Subject to subsection (3), for the purposes of subsection 145(4) of the Act, a level of interference caused by a relevant transmitter is unacceptable if it would have been unacceptable under the Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2012, as in force at the time the relevant transmitter was included in the Register.\n\n> Note: The Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2012 is available, free of charge, from the Federal Register of Legislation at www.legislation.gov.au.\n\n (3) For the purposes of subsection 145(4) of the Act, if:\n (a) after the commencement of this instrument, both:\n (i) a detail of a relevant transmitter changes (relevant change); and\n (ii) the change to the detail is recorded in the Register; and\n (b) the distance of the new device boundary of the relevant transmitter is, on each radial mentioned in item 1 of Schedule 2, equal to or less than the distance of the old device boundary of the relevant transmitter on that radial; and\n (c) but for the effect of this subsection, a level of interference caused by the relevant transmitter, immediately after the change time, would be unacceptable;\n the level of interference caused by the relevant transmitter, immediately after the change time, is not unacceptable because of the relevant change.\n (4) For the purposes of subsection 145(4) of the Act, if:\n (a) after the commencement of this instrument, both:\n (i) a detail of a relevant transmitter changes (relevant change); and\n (ii) the change to the detail is recorded in the Register; and\n (b) the distance of the new additional device boundary of the relevant transmitter is, on each radial mentioned in item 1 of Schedule 2, equal to or less than the distance of the old additional device boundary of the relevant transmitter on that radial; and\n (c) but for the effect of this subsection, a level of interference caused by the relevant transmitter, immediately after the change time, would be unacceptable;\n the level of interference caused by the relevant transmitter, immediately after the change time, is not unacceptable because of the relevant change.\n (5) In subsections (3) and (4):\n\n> change time, for a relevant transmitter, means the time the relevant change is recorded in the Register.\n\n> new additional device boundary, of a relevant transmitter, means the additional device boundary of the transmitter established immediately after the change time, in accordance with this instrument as in force at the change time.\n\n> new device boundary, of a relevant transmitter, means the device boundary of the transmitter established immediately after the change time, in accordance with this instrument as in force at the change time.\n\n> old additional device boundary, of a relevant transmitter, means the additional device boundary of the transmitter established immediately before the change time, in accordance with the Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2012, as in force at the registration time.\n\n> old device boundary, of a relevant transmitter, means the device boundary of the transmitter established immediately before the change time, in accordance with the Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2012, as in force at the registration time.\n\n> registration time, for a relevant transmitter, means the time the transmitter was included in the Register.","sortOrder":9},{"sectionNumber":"2","sectionType":"section","heading":"Device boundary criterion","content":"#### 2 Device boundary criterion\n\n The device boundary criterion is the value of the mathematical expression:\n RP – MP\n where:\n\n| MP | : | is PL(lmn, Lmn) + LOP – Gr; |\n| ------------ | --- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| RP | : | is the horizontally radiated power, measured in dBm EIRP per 30 kHz, for each bearing, σn. |\n| Note 1: | | For a radiocommunications device with AAS, the RP at bearing σn is defined as the sum of the gain of the antenna towards the horizontal plane and towards azimuth σn (dB) and the total radiated power (dBm). This allowance is based on the assumption that beam pointing angles and/or power can be controlled dynamically to ensure RP is not exceeded. |\n| Note 2: | | For RP for a group of radiocommunications transmitters, see subitem 1(2). |\n| LOP | : | is the level of protection. For radiocommunications transmitters that incorporate an AAS, the LOP is -107 dBm per 30 kHz. For all other radiocommunications transmitters, the LOP is -115 dBm per 30 kHz; |\n| Gr | : | is the nominal radiocommunications receiver antenna gain, including feeder loss set to 0 dBi; |\n| PL(lmn, Lmn) | : | is the propagation loss (dB) (calculated under item 3 of this Schedule) of the mth increment on the nth radial. |","sortOrder":12},{"sectionNumber":"4","sectionType":"section","heading":"Additional device boundary of a radiocommunications transmitter","content":"#### 4 Additional device boundary of a radiocommunications transmitter\n\n (1) The additional device boundary of a single radiocommunications transmitter is established as follows:\n Step 1: Calculate the additional device boundary criterion at each m×500 metre increment along each of the n\\-degree radials, where:\n m is each of the integers from 1 through 400; and\n n is each of the integer degrees from 0 (true north) through 359.\n Step 2: For each radial, find the latitude and longitude of the first point on the radial, moving away from the location of the radiocommunications transmitter (that is, with the lowest value of m) where either:\n (a) the additional device boundary criterion, HRP – Lb – CR, is less than or equal to 0; or\n (b) m is equal to 400.\n This point is the end point of the radial.\n Step 3: The end point of each radial is the additional device boundary of the radiocommunications transmitter connected to that radial.\n\n> Note: HRP – Lb – CR (the additional device boundary criterion) is calculated under item 5.\n\n (2) For a group of radiocommunications transmitters the additional device boundary is calculated as if for a single radiocommunications transmitter.","sortOrder":14},{"sectionNumber":"Endnotes","sectionType":"section","heading":"Endnotes","content":"#### Endnotes\n\nEndnote 1—About the endnotes\n\nThe endnotes provide information about this compilation and the compiled law.\n\nThe following endnotes are included in every compilation:\n\nEndnote 1—About the endnotes\n\nEndnote 2—Abbreviation key\n\nEndnote 3—Legislation history\n\nEndnote 4—Amendment history\n\nAbbreviation key—Endnote 2\n\nThe abbreviation key sets out abbreviations that may be used in the endnotes.\n\nLegislation history and amendment history—Endnotes 3 and 4\n\nAmending laws are annotated in the legislation history and amendment history.\n\nThe legislation history in endnote 3 provides information about each law that has amended (or will amend) the compiled law. The information includes commencement details for amending laws and details of any application, saving or transitional provisions that are not included in this compilation.\n\nThe amendment history in endnote 4 provides information about amendments at the provision (generally section or equivalent) level. It also includes information about any provision of the compiled law that has been repealed in accordance with a provision of the law.\n\nMisdescribed amendments\n\nA misdescribed amendment is an amendment that does not accurately describe how an amendment is to be made. If, despite the misdescription, the amendment can be given effect as intended, then the misdescribed amendment can be incorporated through an editorial change made under section 15V of the Legislation Act 2003.\n\nIf a misdescribed amendment cannot be given effect as intended, the amendment is not incorporated and “(md not incorp)” is added to the amendment history.\n\nEndnote 2—Abbreviation key\n\n| ad = added or inserted | orig = original |\n| ---------------------------------------------- | ----------------------------------- |\n| am = amended | par = paragraph(s)/subparagraph(s) |\n| amdt = amendment | /sub‑subparagraph(s) |\n| c = clause(s) | pres = present |\n| C[x] = Compilation No. x | prev = previous |\n| Ch = Chapter(s) | (prev…) = previously |\n| def = definition(s) | Pt = Part(s) |\n| Dict = Dictionary | r = regulation(s)/rule(s) |\n| disallowed = disallowed by Parliament | reloc = relocated |\n| Div = Division(s) | renum = renumbered |\n| exp = expires/expired or ceases/ceased to have | rep = repealed |\n| effect | rs = repealed and substituted |\n| F = Federal Register of Legislation | s = section(s)/subsection(s) |\n| gaz = gazette | Sch = Schedule(s) |\n| LA = Legislation Act 2003 | Sdiv = Subdivision(s) |\n| LIA = Legislative Instruments Act 2003 | SLI = Select Legislative Instrument |\n| (md not incorp) = misdescribed amendment | SR = Statutory Rules |\n| cannot be given effect | Sub‑Ch = Sub‑Chapter(s) |\n| mod = modified/modification | SubPt = Subpart(s) |\n| No. = Number(s) | underlining = whole or part not |\n| o = order(s) | commenced or to be commenced |\n| Ord = Ordinance | |\n\nEndnote 3—Legislation history\n\n| Name | Registration | Commencement | Application, saving and transitional provisions |\n| -------------------------------------------------------------------------------------------------------------- | ---------------------------------- | ---------------- | ----------------------------------------------- |\n| Radiocommunications (Unacceptable Levels of Interference – 1800 MHz Band) Determination 2023 | 17 March 2023 (see F2023L00245) | 18 March 2023 | |\n| Radiocommunications (Unacceptable Levels of Interference — 1800 MHz Band) Determination Variation 2024 (No. 1) | 19 December 2024 (see F2024L01612) | 20 December 2024 | |\n| | | | |\n\n> Note: Endnote 4—Amendment history\n\n```html\n

Provision affected

How affected

s.2.....................

rep. LA s.48D

s.4.....................

rep. LA s.48C

Sch 2, item 2..............

am. F2024L01612

Sch 2, item 3, step 2..........

am. F2024L01612

\n```","sortOrder":20}],"analysis":{"flash_summary":{"complexity_score":8,"scope_assessment":{"changed":true,"description":"The Determination modifies the technical methodology used to identify unacceptable interference compared with the 2012 instrument by prescribing new propagation and boundary calculations and separate protection for AAS (see section 10 defining unacceptable interference and Schedule 2 item 2 for LOP values). It requires use of DEM‑3S terrain data and ITU‑R P.526 for additional device boundaries (Schedule 2 item 6) and precise geodetic computations (Schedule 3 item 3). Section 12 preserves application of the 2012 Determination to transmitters already registered before commencement, but new registrations and any transmitter details recorded after commencement are assessed under the new rules (section 12(2)–(4)). The practical effect is that new or changed transmitter entries must comply with the updated technical tests while pre‑existing registered transmitters retain prior protection unless altered (section 12)."},"complexity_factors":["Technical propagation modelling required: use of ITU‑R P.526 for diffraction loss and DEM‑3S path profiles for additional device boundary calculations (Schedule 2 item 6).","Detailed device boundary algorithm: radial sampling at 100 m increments for device boundary and 500 m for additional device boundary, with up to 400 increments per 360° set of radials (Schedule 2 items 1 & 4).","Many numerical formulas and iterative calculations, including Vincenty’s direct formulae for geodesics to compute latitude/longitude points (Schedule 3 item 3).","Different parameter sets and protection levels: distinct LOP for AAS (–107 dBm/30 kHz) versus other transmitters (–115 dBm/30 kHz) and a separate compatibility requirement (CR = –136.5 dBm/30 kHz) (Schedule 2 items 2 & 5).","Effective antenna height depends on DEM‑3S cell averages, special cell‑index rules and measurement tolerances (Schedule 3 items 1–2).","Accuracy and confidence requirement: parameters must be estimated with ≥95% confidence that true values remain below limits (section 11).","Complex grouping rules for transmitters and receivers (sections 8–9) that affect how radiated power is aggregated for boundary calculations.","Multiple exception and transitional rules (section 10 subsections (2)–(3); section 12) creating conditional scope depending on geography, licence co‑ownership or prior registration.","Interplay with the Register and ACMA powers: device details must be recorded and ACMA may refuse registration if operation could cause unacceptable interference (section 10 note and section 12 transitional rules).","High precision measurement requirements (location accuracy <10 m; antenna height error tolerances) increase implementation and compliance burden (Location and Schedule 3)."],"plain_english_summary":"This Determination sets the technical test for when interference from transmitters under 1800 MHz spectrum licences is ‘unacceptable’. It prescribes how to calculate a transmitter’s device boundary and an additional device boundary using terrain data, propagation models and precise coordinate methods, and sets protection levels (including a separate level for active antenna systems). Spectrum licensees must model, measure and record transmitter parameters so ACMA can refuse registration where operation would cause unacceptable interference."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":8,"scope_assessment":{"changed":false,"description":"The legislation maintains its original technical scope as a spectrum management determination. The 2024 variation (shown in endnotes) made minor amendments to Schedule 2 calculation methods but did not expand the instrument beyond its core purpose of defining interference thresholds for 1800 MHz spectrum licences. The transitional provisions in section 12 preserve continuity with the 2012 predecessor instrument without broadening application."},"complexity_factors":["47+ defined terms in section 5, many cross-referencing external technical standards (ITU-R Recommendations, DEM-3S elevation data, GDA94 geodetic datum)","Nested mathematical formulas across 3 schedules involving: Vincenty's Direct Formulae for geodetic calculations, propagation loss equations with 12+ variables, iterative calculation requirements (convergence to 10^-12)","Dual boundary systems: standard 'device boundary' (100m increments, 40km max) and 'additional device boundary' (500m increments, 200km max) with different calculation methodologies","Conditional logic with multiple exceptions: section 10 has 6 primary conditions for unacceptable interference, 2 exception subsections (10(2) and 10(3)), and a transitional override in section 12","External data dependencies: requires real-time access to DEM-3S digital elevation model, Australian Spectrum Map Grid 2012, and ITU-R Recommendation P.526","Technical parameter specificity: precise values like '54.5 dBm EIRP per 30 kHz', 'effective earth radius factor of 4/3', and modulus calculations for DEM-3S cell identification","Group transmitter/receiver rules with 5+ cumulative conditions that must all be satisfied (sections 8-9)","Active Antenna System (AAS) special provisions with dynamic beamforming assumptions that modify standard power calculations"],"plain_english_summary":"This instrument sets when 1800 MHz mobile transmitters cause “unacceptable interference,” prescribing how to calculate lawful signal boundaries and special limits for tall sites near busy mobile areas. It affects spectrum licence holders, mobile operators and radio engineers who must register and justify equipment, and preserves pre‑March 2023 installations under grandfathering rules. It matters because it protects mobile service quality, prevents mutual disruption and gives ACMA clear grounds to refuse problematic registrations."}},"importantCases":[],"_links":{"self":"/api/acts/radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023","history":"/api/acts/radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023/history","analysis":"/api/acts/radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023/analysis","conflicts":"/api/acts/radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023/conflicts","importantCases":"/api/acts/radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023/important-cases","documents":"/api/acts/radiocommunications-unacceptable-levels-of-interference-1800-mhz-band-determination-2023/documents"}}