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International Civil Aviation Organization
WORKING PAPER / ACP WG-F/27 WP09
2012-09-07

AERONAUTICAL COMMUNICATIONS PANEL (ACP)

TWENTY SEVENTH MEETING OF WORKING GROUP F

Montreal, 17 – 26 September 2012

Agenda Item 4: / Review, update and development of the ICAO Frequency Spectrum Handbook
  • Update of ICAO Policy statements (Strategy)
  • Further development of new Part II, Frequency Assignment Planning

Harmonization of MIFR with ICAO COM lists

Content of the T12 / T13 Notices to be submitted to the BR

(Presented by the Rapporteur of the email correspondence group)

SUMMARY
This paper presents proposals on the harmonization of the ITU Master International Frequency list with the ICAO COM lists. This material was submitted to the email correspondence group but coordination could not be completed. The material in this paper was extensively coordinated with the ITU.
This paper clarifies the information in the various fields of these Notices and provides technical or administrative considerations. Where necessary, information pertinent to these notices will be incorporated in the ICAO Global COM lists to facilitate the automatic generation of these Notices. The proposed methodology for harmonizing the two databases is presented in a separate paper.
ACTION
The meeting is invited to review the material in this paper and to provide any comment.
Action by the meeting is in paragraph 6

1. Introduction

1.1Coordination and registration of frequency assignments for aeronautical radiocommunication and radionavigation systems is taking place in ICAO through the Regional Offices. These Regional Offices maintain the ICAO database of frequency assignments. ICAO also facilitates or carries out the necessary international coordination between aeronautical frequency assignments. In addition, ICAO has established frequency assignment planning criteria to secure that frequency assignments for aviation can operate without causing (or being subject to) harmful interference.

1.2 ICAO is progressing the development of a Global database of (aeronautical) frequency assignments as an element of the ICAO Global (electronic) Air Navigation Plan (eANP). Through this eANP all information contained can be accessed by States. The global database of frequency assignments is being developed through the program Frequency Finder. This program combines database functionality to keep the database current, provides for assessing compatibility of frequency assignments and, through a graphical interface (such as Google Earth or ArcGIS), presents the relevant data on a map. This program also provides for the automatic generation of the T12 / T13 Notices for submission by the relevant authorities to the RITU Radiocommunication Bureau.

1.3Registration of aeronautical frequency assignments is also made in the ITU.Normally registrations should be submitted through the national Telecommunication Administration of the ITU Member Administrations whenever a frequency assignment has been (successfully) coordinated within ICAO. However, submission of these registrations is not taking place on a regular basis (or not at all), resulting in the situation when the aeronautical part of the ITU Master International Frequency Register (MIFR) has become not relevant. The ICAO and the ITU Secretariat are exploring methods and procedures that can be used to update the ITU MIFR and aligning it with the ICAO database of frequency assignments. The procedural aspects relating to such alignment are addressed in a separate working paper. This paper only addresses the material that can be generated by Administrations or ICAO to facilitate the alignment of the ITU and the ICAO databases by the relevant authorities.

1.4The material in this working paper is relevant to the registration of frequency assignments for air-ground communication systems operating in the frequency band 117.975 – 137 MHz. Similar Notices are required for the registration of frequency assignments in other aeronautical frequency bands. This will be addressed in the near future.

2.ICAO COM lists - content

2.1The ICAO frequency assignment plan contains information to secure protection of aeronautical frequency assignments from harmful interference. This information is reflecting the frequency assignment planning criteria that have been developed by ICAO and which are applied in the international coordination of frequency assignments through the ICAO Regional Offices. The frequency assignment planning criteria for VHF air/ground communication systems operating in the frequency band 117.975 – 137 MHz are contained in the ICAO Handbook on Radio Frequency Spectrum Requirements for Civil Aviation; Doc. 9718, Volume II (under development). Frequency assignment planning criteria for other systems are in ICAO Annex 10, augmented as necessary with Regional criteria.

2.2The information contained in the global ICAO frequency assignment plan are:

ICAO Region

State – full name

State – ICAO abbreviation

Location name

Coordinates (in the format degree-minute-second; East/West or North/South)

Service (aeronautical applications such as Tower communications or Area Control Communications)

Designated Operational Coverage (DOC)of the service (service volume). (Operational range and height)

Category (“ICAO” in case the frequency assignment satisfies a requirement in the Regional Air Navigation Plan; in other cases “NAT” (national) if the frequency assignment satisfies specific national requirements)

Remarks- specific to the frequency assignment

2.3On the basis of the identification of the Service, in the program Frequency Finder the Designated Operational Range and the Designated Operational Height have been derived; in some cases this information has been provided by the civil aviation authorities.

3.Using the ICAO COM lists to generate T12 / T13 Notices

To facilitate incorporation of the frequency assignments from the ICAO frequency assignment plan into MIFR, the ICAO information relevant to the frequency assignment has to be converted in the format used by the ITU. The required format is in the form of the ITU T12 and T13 Notices that would allow for electronic submission to the ITU. The T12 Notice relates to details pertaining to the ground transmitting station; the T13 Notice relates to the ground receiver station. An example of these Notices is reproduced in Appendix A to this paper. No details are (to be) provided for the aircraft station (Re. Article 11.14 of the ITU Radio Regulations), except the power characteristics of aircraft in T13 Notice.

4.Detailed review of the T12 Notice (Ground-to-air communications).

The T12 notice consists of three sections. The first section is the HEAD section. The last section is the TAIL section. Between the HEAD and TAIL sections, there is NOTICEsection. The NOTICE section shall contain subsectionANTENNA describing transmitting characteristics of the assignment. Sub-section <ANTENNA> should contain sub-sub-section RX_STATIONdescribing the Designated Operation Coverage of the transmitting station. The fields to be notified on T12 notice are listed below with sample values. When only one value is allowed for a field, it is indicated in the text.

<HEAD>(Beginning of the HEAD section with data for all notices- mandatory field)

t_adm=F(ITU symbol of the notifying administration - mandatory)

</HEAD>(End of the HEAD section - mandatory)

The field t_adm contains the symbols which are designating the (telecommunication) Administration which is responsible for the Notice. The table of symbols is contained in the Preface to the BR international frequency information circular (Terrestrial Services) which is published by the ITU every two weeks and available at (Re. Preface, Chapter IV, Section 1, Table “Administrations”).

Note: the same <HEAD> is included in both the T12 and the T13 Notice.

<NOTICE>(Beginning of NOTICE section with data related to the first notice - mandatory)

t_notice_type=T12(The type of notice - mandatory. T12 is the only allowed value for transmitting ground-based stations)

All T12 notices are identified in the field t_notice_type with “T12”. The types of Notices are described in the Preface, Chapter III, Section 2.

t_fragment=NTFD_RR(Part of the ITU database to be updated. NTFD_RR – for Master Register – mandatory. NTFD_RR is the only allowed value)

This field isused to distinguish between notification for the MIFR, for Regional agreements and for coordination procedures. The code NTFD_RR is used for notifications under Art. 11 of the Radio Regulations for recording in the MIFR, so all notices should identify “NTFD_RR”.

t_prov=RR11.2(Provision of the RR under which this notice is submitted – mandatory. RR11.2 is the only allowed value for T12 notices)

This field provides the provision code of the RadioRegulations under which the noticehas been submitted. All notices are submitted pursuant Art. 11.2 of the Radio Regulations; all notices should identify RR11.2.

t_action=ADD(Action - mandatory. ADD = new notice)

t_action can be: ADD – for notification of new assignments

SUPPRESS – for suppression of the assignments recorded in the MIFR

MODIFY – for modification of the assignments recorded in the MIFR

Note: The ITU/MIFR does not keep a record of deletions from the frequency list

t_adm_ref_id=803669(Unique identifier of the assignment given by the administration - optional)

This field contains the unique identification code given by the ITU administration to the assignment.

t_freq_assgn=122.350(Assigned frequency, MHz - mandatory)

This field identifies the “Assigned Frequency” as defined in Article 1 of the Radio Regulations. Article 1 No. 1.148 defines the assigned frequency as “the centre of the frequency band assigned to a station”.

t_long=+0012147(Longitude of the transmitter - mandatory)

t_lat=+433644(Latitude of the transmitter - mandatory)

These fields are used to identify the geographical coordinates ofthe transmitter site. The latitude and the longitude of the transmitter station can be provided in the format required. (+ is N/E; - is S/W). It requires conversion of the format used in Frequency Finder (Degree/Minute/Second N/S or Degree/Minute/Second E/W).

t_site_name=TOULOUSE ACC(Site name - mandatory)

This field is used to identify the name of the locality by which the transmitting station is known or in which it is situated. This information is available in the ICAO global frequency list. It should be noted that in many cases the same site name is being used for more than on frequency assignment. If necessary / useful, the type of (aeronautical) service could be added to the site name (e.g. Toulouse ACC, Toulouse TWR). Alternatively, a serial number can be added to the site name.

t_emi_cls=A3E--(Emission class - mandatory, see Appendix 1 to the Radio Regulations (RR))

This field is used to identify the class of emission. For air/ground voice communications, the class of emission could be A3E-- (without using the fourth and the fifth symbol and replace them with dashes). A proper class of emission for the digital data link communication systems operating in the band 117.975 – 137 MHz (VDL Mode 2 and VDL Mode 4) needs to be provided. Appendix 1 to the Radio Regulations contains provisions relating to the identification of classes of emission.

t_d_inuse=2007-11-20(Date of bringing the frequency assignment into use - mandatory)

This field is used to identify the date (actual or foreseen, as appropriate) of bringing thefrequency assignment (new or modified) into use. This information is not available in ICAO; it is proposed to replace it with the date when the frequency assignment has been entered in the ICAO database. In cases such date is not available, the date of the completion of the ICAO global frequency list could be inserted (or alternatively, any other date). The date can be provided in the desired format.

t_bdwdth_cde=6K00(Bandwidth- mandatory, see Appendix 1 to the Radio Regulations )

This field (is assumed to) provide the necessary bandwidth. The necessary bandwidth is defined in No 1.152 of the Radio Regulations. Appendix 1 to the Radio Regulations contains methods relating to determination of the necessary bandwidth, e.g. one of the methods is use of the formulae and examples of necessary bandwidths and designation of corresponding emissions given in Recommendation ITU-R SM.1138-2. For A3E emissions bandwidth code is 6K00 in accordance with Recommendation ITU-R SM.1138-2. If the other class of emission for the digital data link communication systems operating in the band 117.975 – 137 MHz (VDL Mode 2 and VDL Mode 4) is provided, the methods to determine the necessary bandwidth in Appendix 1 to the Radio Regulations shall be taken into account.

t_site_alt=Xxx(The altitude (meters) of the site above mean sea level - optional)

This field is not required and will not be used in the Notice

t_addr_code=A(Symbol for the address of administration responsible for station - mandatory)

This field contains the symbol for the address of the (telecommunication) administration responsible for thestation and to which communication should be sent.This information is not available in the ICAO data base of frequency assignments. Frequency assignments are coordinated in ICAO directly with the relevant aeronautical administrations. The values for address codes to be used are listed in the Preface, Chapter IV, Section 3. The addresses themselves, as in Chapter IV, Section 3 of the Preface can (should?) be inserted in the ICAO database for reference purposes.

t_ctry=F(Geographical area where the transmitter is located - mandatory)

This field identifies the country (or territory) the transmitter is located. This information is available in the ICAO frequency list and can be provided, using the ITU codes for geographical areas. (Re. Preface, Chapter IV, Section 2, Table “Geographical areas”) Special attention can be given to dependent territories.

t_op_hh_fr=00:00(The starting time for the hours of operation – mandatory, 00:00 is the only possible value)

t_op_hh_to=24:00(The ending time for the hours of operation – mandatory, 24:00 is the only possible value)

These fields identify the regular hours of operation From (UTC) To (UTC) of the frequency assignment, in UTC. For all aeronautical frequency assignments 24 hrs a day operation is to be assumed.

t_stn_cls=FD(Class of station- mandatory. FD – ground based station in AM(R)S)

This field identifies the Class of station and contains the “class of station code” as per thePreface, Chapter IV, Section 6, “Class of stations”. For aeronautical (ground) stations operating in the Aeronautical Mobile (R)Service, the identification is “FD”. Also, in some rare cases FA can be used to identify an aeronautical transmitting station, which operate both in the aeronautical mobile (R) and the aeronautical mobile (OR) services.However, the operation of the aeronautical mobile (OR) service is allowed only in the countries listed in the RR No.5.201 and RR No.5.202, so symbol FA can be used only by these countries.

Note: part of the band 117.975 – 137 MHz is shared with the aeronautical mobile (OR) service. ICAO does not distinguish between assignments that have been made for stations the (R) and the (OR) service. All stations in the ICAO frequency table are treated as providing AM(R)S.

t_nat_srv=CV(Nature of service- mandatory. CV – correspondence of a private agency, CO – official correspondence)

This field identifies the Nature of service and contains the “nature of service code” as per the Preface, Chapter IV, Section 7, “Nature of service Class of stations”.For stations operating in the

Aeronautical Mobile (R) Service, the identification is normally “CO”(official correspondence). Aeronautical operational control should use the identification “OT” (station open exclusively for correspondence of the service concerned) although CV (station open exclusively to correspondence of a private agency) may be appropriate. CP and CR (Public correspondence) shall not be used in accordance with RR 43.3.

<ANTENNA>(Beginning of sub-section with antenna information - mandatory)

t_pwr_xyz=Y(The type of power - mandatory. Y- mean power, X- peak, Z - carrier)

This field contains the symbol (X, Y or Z, as appropriate) describing the type of power (see Article 1 of the RR) corresponding to the class of emission. The symbols that should be used are in the Preface, Chapter IV, Section 8. For all transmitters in the AM(R)S the type of power is mean power as per No. 1.158 of the Radio Regulations(symbol Y).

t_ant_dir=ND(Directional (D) or non-directional (ND) antenna- mandatory)

This field contains information on the Antenna directivity, the indicator showing whether theantenna is directional (D) or non-directional (ND). In almost all cases the antenna used in the AM(R)S is non-directional and, unless more detailed information is provided to ICAO, non-directional antennas are assumed in frequency assignment planning. In case no specific information is provided to ICAO, this field will be set to “ND”.

t_gain_type=D(Type of antenna gain -mandatory. The only allowed value is D - relative to half-wave dipole)

This field contains information on the antenna gain type. The type of antenna gain can be:

I - Isotropic gain;

V - gain relative to a short vertical antenna; and

D - gain relative to a half-wave dipole (see RR1.160)

In the frequency bands non-shared with space services (this is the case of VHF AM(R)S),the type of antenna gainalways should be the gain relative to a half-wave dipole in line with the field “t_pwr_eiv” below.

t_gain_max=5.15(Maximum antenna gain,( dB) - mandatory, if t_pwr_dbw is not provided)

This field contains information on the maximum antenna gain. The maximum antenna gain is the gain (relative either to isotropicantenna or to a short vertical antenna or to a half-wave dipole, as appropriate) of the transmitting antenna, see RR No. 1.160.

For stations in the AM(R)S the antenna gain relative to isotropic antenna is typically 3dB. However, this value should be converted to the gain relative to a half-wave dipole in accordance with the field “t_gain_type”. The difference between the isotropic antenna gain and the gain relative to a half-wave dipole is 2.15 dB (Ref. Table 1 in Annex 1 to Recommendation ITU-R P.341). So, the gain relative to a half-wave dipole is 5.15 dB.

t_hgt_agl=(Height of transmitting antenna above ground level, m - optional)

This field contains information on the height of the antenna ground level, in meters. This information is optional and should in principle not be provided as it is not included in the ICAO frequency list. Alternatively, a standard height of 30 meters can be used, which may apply to most cases.

t_pwr_eiv=E(Type of radiated power - mandatory. The only allowed value is E - e.r.p)

This field contains information on the type of radiated power. The type of radiated power can be:

I - Equivalent isotropic radiated power (e.i.r.p) RR1.161;

E - Effective radiated power (e.r.p) RR1.162;

V - Effective monopole radiated power (e.m.r.p) RR1.163

In the AM(R)S, for compatibility calculations performed in ICAO, the e.i.r.p is being used, which is the sum of the transmitter power, cable losses and antenna gain. However, for notification to the ITU, in the frequency bands non-shared with space services (this is the case of VHF AM(R)S) the Type of Radiated Power shall be E.

t_pwr_ant=+11(Power to the antenna (dBW) – mandatory, if t_pwr_dbw is not provided)