Third Interim Report of the Correspondence Group Dealing with AMS(R)S Spectrum Issues

Aeronautical Communications Panel (ACP)

29th Meeting of Working Group F (WG-F)

Nairobi, Kenya, 5 – 13September 2013

Third Interim Report of the Correspondence Group

Dealing with AMS(R)S Spectrum Issues

(Presented by WAKAMATSU, Hirofumi, Coordinator CG-AMS(R)S)

1. Background

The 28th meeting of the Working Group F considered the WP16, interim report of the WG-F correspondence group dealing with AMS(R)S. The meeting agreed that the WG-F AMS(R)S correspondence group should continue and should focus continuing development of material for contributions to WP4C, and to begin development of proposed procedures for ICAO to utilize in the event administrations ask for validation of their AMS(R)S traffic requirements.

This document provides thethirdinterim report of the correspondence group to be submitted to the 29th WG-F meeting.

2. Discussions

2.1According to the agreement and guidance of the WG-F/28 meeting, the correspondence group considered its objectives and terms of reference, and maintained them. The work plan of the group was slightly updated based on the agreement of WG-F/28.

2.2The coordinator provided draft proposal paper on the ICAO procedure to respond Res. 222 and there were some approvals and no objection from the members. Accordingly, the draft proposalpaper is attached as shown in Annex 1 of theAttachment for consideration.

2.3The coordinator also providedthe result of the third WP 4C meeting with the necessary areas of work to complete the new Recommendation are summarized in seven items as shown in Annex 2 of the Attachment.

2.4As there was no comment from the member, the coordinator then providedpreliminary draft elements of proposed modifications on the working document to be used by respective Administrations and ICAO in preparation of contributions to the 4th WP 4C meeting as shown in Annex 3 of the Attachment.

2.4.1After the last WP 4C meeting, an informal corresponding group was set up aiming to accelerate the discussion for the seven open issues as reported by Annex 2 of Attachment. The informal correspondence group is actively exchanging the comment and/or suggestions toward the completion of the work at next WP 4C meeting.

3. Conclusion and proposal

The ThirdInterim Report of the Correspondence Group dealing with AMS(R)S spectrum Issues is provided for the 29th meeting of the Working Group F as shown in the Attachment.

WG-F members areasked to consider and agree this interim report for active participation in the work of WP 4C toimprove method of calculation of spectrum requirements for the AMS(R)S communications responding to Resolution 422 (WRC-12).

Attachment:

The Third Interim Report of the Correspondence Group Dealing with AMS(R)S Spectrum Issues

Doc. WG-F/CGAMSRS005

The Third Interim Report of the Correspondence Group

Dealing with AMS(R)S Spectrum Issues

16Aug.2013

1. Introduction

The 28th meeting of the Working Group F considered the WP16. It was stated during the presentation that WP16 provided an interim report of the WG-F correspondence group dealing with AMS(R)S.

Following the discussion the meeting agreed that the WG-F AMS(R)S correspondence group should continue and should focus on continuing development of material for contributions to WP4C, and to begin development of proposed procedures for ICAO to utilize in the event administrations ask for validation of their AMS(R)S traffic requirements.

This document provides a draft third interim report of the correspondence group to be submitted to the 29th WG-F meeting.

2. Objectives of the Correspondence Group and its Terms of Reference

Objectives of the Correspondence Group is “to consider the role of ICAO responding to invite ICAO by Res.222(Rev. WRC-12) including method of the evaluation by ICAO of the AMS(R)S traffic requirements and to consider improvement of methodology for determining AMS(R)S spectrum requirements especially on the traffic requirements responding to Res.422(WRC-12)”.

Terms of Reference for the group are described below.

(1) To exchange information on the AMS(R)S spectrum issues in following subjects.

a) Responding to "invites ICAO" section of Res. 422(WRC-12)

Methods of providing and evaluating AMS(R)S traffic requirements and conditions to ensure required quality of service for the AMS(R)S communications in developing ITU-R Recommendation of methodology to calculate AMS(R)S spectrum requirements

b) Responding to "invites ICAO" section of Res. 222(Rev. WRC-12)

Method of the evaluation by ICAO of the AMS(R)S traffic requirements received from individual administrations, on the basis of the known global and regional aviation traffic requirements, including the time-scale of regional and global communication requirements.

(2) To report the results of the discussion in the correspondence group to the Working Group and to suggest appropriate actions to be taken by ICAO and aviation community.

3. The work plan for the Correspondence Group

The work plan for the Correspondence Group is revised as follows.

3.1 For the WP 4C meetings to be held in September 2013

Based on the results of previous WP 4C meetings;

(1) Consider output documents provided by WP 4C meetings especially on the methods of calculation of AES count and volume of traffic requirements to ensure required quality of service for the AMS(R)S communications.

(2) Consider improvement of those methods as more applicable and practicable procedure as draft new Recommendation.

(3) Consider method of validation for the calculated spectrum requirements

(4) Provide materials to be used for respective Administrations and ICAO developing contributions to the next WP 4C meeting.

(5) Report above results to the WG-F meetings

3.2 For the ICAO role for Res. 222

Based on the results of previous WG-F meetings;

(1) Consider procedures to evaluate/validate AMS(R)S traffic requirements received from administrations

(2) Consider possibility of obtaining appropriate supporting information for the evaluation of AMS(R)S spectrum requirements such as a database of global and regional aviation traffic requirements

(3) Confirm role and position of ICAO relating to AMS(R)S spectrum prioritization and protection

(4) Report above results to the WG-F meetings

4. Discussions

4.1 ICAO role for Res. 222

The coordinator provided Draft proposal paper on the ICAO procedure to respond Res. 222, as shown in Annex 1, and distributed it to the members of the correspondence group for their consideration.

As there were some approvals and no objection from the members, the coordinator would like to submit the Draft proposal paper as output of correspondence group to WG-F 29th meeting for the consideration.

4.2Results of the 3rd WP 4C meeting

The 3rd WP 4C meeting was held in 25April – 1 May 2013, and updated the working document by considering three input documents, Doc. 4C/143(G), 157(CAN,USA), 167(J). The text intended for the new ITU-R Recommendation was separated as PDNR (Preliminary Draft New Recommendation) document with methodology to calculate spectrum requirement attached, from the working document. A list of the main actions which are required to enable completion of the new Recommendation was provided.

4.3Preparation for the 4th WP 4C meeting to be held in September 2013

According to the agreement of the WG-F/28 meeting, the coordinator updated the work plan of the group and provided a paper describing preliminary discussions on the WP 4C working documentas shown in Annex 2, and distributed them to the members for their consideration.

As there was no comment from the member, the coordinator then providedpreliminary draft elements of proposed modifications on the working document to be used for respective Administrations and ICAO in preparation of contributions to the 4th WP 4C meeting as shown in Annex 3.

5. Conclusion and proposal

The Third Interim Report of the Correspondence Group dealing with AMS(R)S spectrum Issues is provided for the 29th meeting.

WG-F members areasked to consider this interim report and actively participate the work of WP 4C forimproving method of calculation of spectrum requirements for the AMS(R)S communications responding to Resolution 422 (WRC-12) and to discuss on the role of ICAO in the process of frequency coordination as “invite ICAO” in the Resolution 222(Rev. WRC-12) based on Draft proposal paper on the ICAO procedure to respond Res. 222, as shown in Annex 1, proposed by the Correspondence Group dealing with AMS(R)S spectrum Issues.

Annexes

1. DRAFT CG AMS(R)S ICAO Procedure to respond Res. 222

2. Discussions on WP 4C Working Document (Attachment of Annex 1 and 17 to Doc.4C/173)

3. Draft elements of proposed modifications on theMethod of calculation of spectrum requirements for the AMS(R)S communications in the 1.5/1.6GHz bands

Annex 1

DRAFT

CG AMS(R)S

ICAO procedure to respond Res. 222

WG-F/28 Report

6.5.3.1WP16 provided the second interim report of the correspondence group dealing with AMS(R)S spectrum issues. The Correspondence Group considered its objectives and terms of reference, and maintained them. The work plan of the group was updatedbased on the discussions in the WG-F/27 meeting. WP16 also described discussions on WP 4C working documents, especially on method to estimate AES count and volume of traffic, andprovided preliminary draft elements of proposed modifications on the working document to be used by respective Administrations and ICAO in preparation of contributions to the 3rd WP 4C meeting. The meeting was asked to actively participate in the work of WP 4C to improve the method of calculation of spectrum requirements for the AMS(R)S communications responding to Resolution 422 (WRC-12). Further, members were encouraged to open discussions on the role of ICAO in the process of frequency coordination, and in particular how to satisfy the “invites” in Resolution 222 (Rev. WRC-12) dealing with ICAO without causing undue burden on ICAO.

6.5.3.2Following discussion the meeting agreed that the WG-F AMS(R)S correspondence group should continue and should focus on continuing development of material for contributions to WP4C, and to begin development of proposed procedures for ICAO to utilize in the event administrations ask for validation of their AMS(R)S traffic requirements.

WRC-12

invites

2ICAO to evaluate and, as appropriate, comment on the AMS(R)S traffic requirements received from individual administrations, on the basis of the known global and regional aviation traffic requirements, including the time-scale of regional and global communication requirements,

Proposed procedures

(1) Administrations (states) planning new system and wishing to evaluate their AMS(R)S traffic requirements under Resolution 222 may submit their traffic requirements with supporting information to ICAO.

(2) To respond to such requests, ICAO will consult with its membership referring to known global and regional aviation traffic requirementson request.

(3) ICAO will aim to respond in time for relevant coordination meetings. Normally the consultation will take place through appropriate meeting in ICAO such as working group on spectrum management, but may be conducted by correspondence if required to meet coordination meeting deadlines.

Annex 2

Discussions on WP 4C Working Document

（Attachment of Annex 1 and 17 to Doc.4C/173）

26 July 2013

CG AMS(R)S

1. Introduction

The working document contained in Annex 14 to Document 4C/91 was revised in particular to separate out the text intended for the new ITU-R Recommendation (PDNR: Preliminary Draft New Recommendation) into a separate document as Annex 1 to Doc. 4C/173. Three approaches to estimate AES count which were proposed for methods of calculating AMS(R)S spectrum requirements in the previous text, converged into one approach based on historical operational data in the content of the annex to the new Recommendation.

The working document which remained as Annex 17 to Doc. 4C/173 was also revised to contain a list of the main actions required to enable completion of the new Recommendation.

Both output documents are retained as attachments to the Chairman’s report, Doc. 4C/173, for further work at the next WP 4C meeting.

2. General Discussion

Necessary areas of work to complete the new Recommendation are described in item 8 of the working document, Annex 17 to Doc. 4C/173:

1. All formulas need to be reviewed for consistent variable names and use of suffixes.
2. Figure 1 should be replaced with a new diagram to illustrate the current methodology.
3. A list of the input parameters should be provided (see Appendix A to Annex 1 of the PDNR).
4. An example calculation to illustrate the use of the methodology should be included (seeAppendix B to Annex 1 of the PDNR).
5. Section 4.3 of Annex 1 of the PDNR identifies a number of aspects which should be addressed to allow the methodology to be used for planned new broadband safety services.
6. In section 5.2 of Annex 1 of the PDNR, a method to determine the aggregate spectrum requirements for a satellite network which employs frequency re-use should be provided.
7. The principles in Annex 2 of the PDNR to be reviewed.

3. Discussion

WG-F members are invited to consider on the work items of the action list in Annex 17 to Doc. 4C/173, to elevate the PDNR to a draft new Recommendation.

Annex 3

Draft elements of proposed modifications on the

Method of calculation of spectrum requirements for the AMS(R)S communications in the 1.5/1.6GHz bands

{Editorial Note: Review all notations used in this document to ensure consistency and ease of understanding by all readers.}

1General

……………….

2Estimation of AES count and volume of traffic per AES to be handled with the satellite system under consideration

{Editorial Note: it is suggested to use the term “information volume” to refer to the data transmitted to and from the user, excluding the overheads which are required in the transmission of the data. The title and content of section 2 should be reviewed so as to ensure consistent language in this regard.}

From an operational and economical point of view, it is generally desired that normal traffic in awide area will be handled by the global beam, and high traffic in congested airspace be handled by spot beams. The advantage of the global beam is that it covers areas that would otherwise not be covered by the spot beams. In a typical deployment scenario a cluster of spot beams may be activated to serve aircraft along the high traffic air routes with the outlying aircraft served by the global beam. Although it is possible for the global beam to provide many of the same services as the spot beams the global beam is likely to be used for broadcast messages, signalling, and logging aircraft on to the network. Spacecraft design may include adoption of spot beams to provide services where it is more spectrally or powerwise efficient to do so. It is important to know how many AESs are being served spot beams and global beams during the peak period. Satellite networks utilizing advanced multi-spot beam configuration would be handled in a similar manner, except that the number of AESs within a cluster of beams would be required at this step.

As discussed above, the number of AESs (AES Count) within a specified beam to be handled within the satellite system under consideration should be determined. The AES Count is defined as the peak number of actually operating AESs within the specified area of the satellite network and logged on to that satellite network under consideration in the busiest hour of the year for the AMS(R)S traffic portion of the network, where the busiest hour is the busiest hour of that particular area/beam. Note that the AES count should include only those AES which are expected to make use of the satellite network.

The AES Count, is a fundamental parameter required for the estimation of the spectrum requirement for the AMS(R)S communications. The approach used to determine this number is based on the assumption that historical data for the total number of logged-on AESs within each beam of the AMS(R)S system within the critical time period is available, and estimates of future requirements may be made based on this historical data, withasuitable adjustment to account for increasing or decreasing demand in the future.

It should be noted that the above approach is not intended for use by newly planned AMS(R)S systems. This approach is applicable to established systems and should provide the most accurate estimate of AMS(R)S spectrum requirements.

An AMS(R)S system may consist of several GSO satellites, which may have overlapping beams insome areas. The spectrum requirements are determined separately for each beam within each satellite, and in areas of overlap there is a risk that AESs are double-counted, i.e. assigned to twosatellites at the same time. Hence, when determining the AES count in areas of overlapping coverage, it is necessary to ensure that the number of AESs is suitably apportioned between the satellites. Such consideration does not apply to situations where one satellite is a backup or hotstandby satellite.

The AES count per beam (ACb) is best determined through historical statistics from the relevant satellite systemwith a few years of operational experience, with adjustments made for projected short term changes in the actual number of operating aircraft.

The traffic data for both circuit switched voice traffic and the packet data traffic is processed on anhourly basis based on the raw call data records. It is possible to gather the following information on an hourly basis for each calendar day of any given month.

–Satellite network/associated GES

–Beam: Global/spot within the satellite

–Calendar day

–Hour (0-23 hours) (Note: 1st hour recorded as “0 hour”, 24th hour recorded “23rd hour”)

–AES identification number communicated with satellite network/associated GES

–Time of start and end of the communication.

The following information should also be used to estimate volume of traffic, where the traffic consists of the user information and does not include the overheads associated with transmission of the traffic:

–Traffic unit (kbits for packet data traffic (forward and return directions) and minutes for circuit switched traffic).

–Volume of traffic (kbits or mins).

Based on the above information it is possible to identify three busy hours within a given year for each category of voice and packet data traffic in each beam of satellite network by analysing the call records gathered in the GES serving such a beam. There are occasions where a beam could be served by more than one GES, in which case the busy hours traffic should be determined separately for each GES. Havingidentified the three busy hours, the AES count is determined for each of those busy hours and the average value of the AES count for those three busy hours is used in the further analysis. These steps are undertaken separately for the voice and data traffic so that two values for the AES count are determined – one applicable to voice traffic and the other applicable to the data traffic. An underlying assumption here is that there is not a significant difference in volume of traffic associated with each of the three busy hours.