23cm band: Amateur radio coexistence with Sat-Nav

Galileo LogoThe Chair of IARU Region 1 Spectrum Affairs, Barry Lewis G4SJH, reports on the meeting of the ITU-R Working Party 4C (WP4C) July 5-13 which discussed the amateur radio 1240 MHz band.

On the IARU-R1 site he writes:

During the period 5 – 13 July 2021, the preparatory work for WRC-23 agenda item 9.1b continued in ITU‑R Working Party 4C (WP4C). (See Region 1 Feb 23rd news item for further background). The IARU member representatives from Australia, Brazil, Canada, Germany, Japan, Norway, UK and USA, participated in the meeting and delivered additional information on amateur activities in this key microwave band

Preliminary studies came from France based on the ongoing CEPT work to provide initial estimates of separation distances required between RNSS GALILEO receivers and a sample of amateur emissions. The European Commission GALILEO team provided a set of observations pertaining to a RNSS interference event in northern Italy.

The work contributed by France, although needing refinement, is going in a good direction, using ITU‑R recommended propagation models and assumptions based on operating scenarios provided by the amateur community. Further work is needed to take account of the large disparity between the RNSS service receiver bandwidths and the frequency band offsets of the amateur applications based on the measurements carried out by Germany.

The RNSS community have updated their RNSS receiver protection criteria with an update to ITU‑R Recommendation M.1902 that now includes parameters relevant to the GALILEO E6 signal block. However these criteria only distinguish between a narrow band and wide band interferer level at the receiver and take no account of offset frequency in the receiver bandwidth or any time variance.

The IARU is working to ensure the amateur services are realistically represented in the studies as they move forward. It remains vital that national amateur communities present their views on the importance of this band to their national regulators in a consolidated and consistent manner. The work will continue throughout the year and beyond both in ITU‑R and in the regional telecommunications organisations and the IARU is committed to ensure every group hears the amateur position on this important microwave band.

Read Barry’s full post at
https://www.iaru-r1.org/2021/23cm-band-and-sat-nav-coexistence-preliminary-studies-considered-in-itu-r-wp4c/

Read the IARU Summary Meeting Report at
https://www.iaru-r1.org/wp-content/uploads/2021/07/Report-from-WP4C_Jul-2021Rev1.pdf

Recent activity on the 23cm band RNSS Coexistence Studies

CEPT LogoThe Chair of IARU Region 1 Spectrum Affairs, Barry Lewis G4SJH, reports on the work being done in defending the interests of the Amateur Services in the 1240-1300 MHz band.

His IARU Region 1 post reads:

IARU is continuing to represent the amateur services interests in the 23cm band Galileo/GLONASS radio navigation satellite service coexistence discussions in the CEPT project teams.

The most recent CEPT SE40 project team meeting was held from 24th to 26th March 2021 and the IARU R1 was represented by Barry Lewis, G4SJH (Region 1 SRLC chair). At that meeting the first coexistence calculations were introduced by one CEPT administration, based on some initial assumptions about the amateur service operation. The IARU is continuing to work with the regulators to refine the details of these assumptions and make them and the calculations more representative of typical amateur station characteristics and band usage. These first calculations are considered only as a starting point and the meeting agreed that further work is needed to develop the calculations into a more comprehensive study.

Measurement campaigns have shown that the potential for coexistence depends very much on the frequency of the amateur service transmissions in the 23cm band with respect to the RNSS receiver bandwidth. This aspect needs to be considered more carefully once the initial scenarios and calculations are agreed.

In addition the IARU continues to have questions about the protection criteria required by the RNSS receivers and in particular how they relate to RNSS operational and service provision behaviour. IARU has ensured alignment of the amateur and amateur service information being used in CEPT with that being used in the parallel work in the ITU‑R relating to WRC-23 AI 9.1b.

Source IARU Region 1 https://iaru-r1.org/

The meeting Input paper “Amateur versus RNSS, interference areas” that was submitted by France as well as other meeting documents can be downloaded from
https://cept.org/ecc/groups/ecc/wg-se/se-40/client/meeting-documents/?flid=28532

23cm band in the spotlight with regulators

RNSS - Credit IARU Region 1

RNSS – Credit IARU Region 1

The Chair of IARU Region 1 Spectrum Affairs, Barry Lewis G4SJH, reports on the meeting of the ITU‑R Working Party 4C (WP4C) on February 15-19 which discussed the amateur radio allocation at 1240-1300 MHz.

On the IARU Region 1 site he writes:

During the week February 15–19, the preparatory work for WRC-23 agenda item 9.1b continued in ITU‑R Working Party 4C (WP4C). The WRC agenda item has initiated technical studies on coexistence between the radio navigation satellite service (RNSS) and the amateur services in the 23cm band. As usual, the IARU participated in the meeting and delivered key information on amateur activities in this important microwave band. This information is vital to ensure the amateur services are realistically represented in the studies as they move forward.

It remains vital that national amateur communities present their views on the importance of this band to their national regulators in a consolidated and consistent manner.

To assist with this the IARU-R1 is developing supporting material that member societies can refer to when addressing the topic with their national regulator.

The work on this topic will continue throughout the year and beyond both in ITU‑R and in the regional telecommunications organisations and the IARU is committed to ensure every organisation understands the amateur position on this important microwave band.

Source IARU-R1 https://www.iaru-r1.org/2021/23cm-band-in-the-spotlight-with-regulators/

The ITU‑R WP4C Summary Meeting Report notes “The only administration that can be considered supportive towards proper treatment of the Amateur Services in this work is Germany”, read the report at https://www.iaru-r1.org/wp-content/uploads/2021/02/Report-from-WP4C_Feb-2021.docx

1240-1300 MHz ham radio band discussed by CEPT ECC SE40

CEPT LogoCEPT ECC has released its news summary for January 2020 that includes the SE40 Rome meeting on January 14-16 which discussed compatibility between RNSS and Amateur Services in 1240-1300 MHz.

The coexistence between the Radio Navigation Satellite Service (RNSS) and the Amateur Services in the frequency band 1240 – 1300 MHz was discussed by the CEPT ECC SE40 Working Group. The IARU presented possible scenarios to be taken into account in the sharing studies. The meeting agreed that further work on this WI will be developed in the SE40 Forum.

The papers, Amateur vs RNSS – Amateur scenarios – initial ideas, Draft Report RNSS vs Radioamateur, and Draft Minutes, along with other SE40 Rome meeting documents can be downloaded via
https://www.cept.org/ecc/groups/ecc/wg-se/se-40/client/meeting-documents/?flid=27486

The CEPT ECC January news summary is at
https://cept.org/ecc/news/ecc-monthly-news-summary-for-january-2020/
https://twitter.com/CEPT_ECC

The Galileo GNSS constellation and 1296 EME operation
http://www.southgatearc.org/news/2020/february/the-galileo-gnss-constellation-and-1296-eme-operation.htm

2006 article Potential Interference To Galileo From 23cm Band Operations by Peter Blair G3LTF
http://www.southgatearc.org/articles/galileo.htm

Threat to Amateur Radio 23cm band

Galileo LogoA joint paper by France, Lithuania, Malta, Slovenia and The Netherlands for the CEPT CPG meeting in Ankara, August 26-30, attacks the continued use by Radio Amateurs of our 1240-1300 MHz band.

This is the final CEPT CPG meeting in preparation for the ITU World Radiocommunication Conference 2019 (WRC-19) to be held in Sharm el-Sheikh, Egypt, October 28 to November 22. This conference will define the Agenda Items for WRC-23.

Paper AI10 – Proposal on AS-RNSS says:

Galileo is close to full operational capability and its E6 signals in the band 1260-1300 MHz will support new services such as the free-to-use Galileo High Accuracy Service, and also robust authentication, expected to be used by a variety of applications including autonomous vehicles and the Internet of Things (IoT).

Several cases of interference to Galileo E6 receivers from amateur service emissions have occurred in the recent past, sometimes at significant distance, and have taken several hours or even days to be eliminated. There is therefore a serious concern that as Galileo E6 receivers are deployed and used more widely, cases of interference from amateur stations will rapidly grow in number.

A WRC-23 agenda item is necessary to address this issue because:

1. Unregulated use of the band 1240-1300 MHz by the amateur service is a serious source of harmful interference to RNSS receivers. This is demonstrated by experience.

2. The number of Galileo receivers in 1260-1300 MHz will increase dramatically, and interference cases will multiply if not addressed timely.

3. Galileo and other RNSS systems will deploy at global scale, and interference scenario between amateur emissions and RNSS receivers include cross-border cases. The issue is therefore of international nature and is to be addressed in the ITU framework.

4. Galileo is a major European asset, and a decision at WRC-23 is essential to be compatible with the roadmap of deployment of Galileo receivers in this band.

Download Paper: AI10 – Proposal on AS-RNSS from
https://cept.org/ecc/groups/ecc/cpg/client/meeting-documents/?flid=10031

Also see the IARU paper: RNSS Proposal WRC-19 AI 10 at the same URL

Some background information is at
https://amsat-uk.org/2019/05/31/1240-1300-mhz-band-discussed-by-cept-wgfm-and-cpg-pta/

European Commission Joint Research Centre report written 2014 and published 2015 on Compatibility between Amateur Radio Services and Galileo in the 1260-1300 MHz Radio Frequency Band. It reports the effect of transmissions of 0.1, 1 and 15 watts EIRP on a Galileo receiver up to 10 km away – download PDF here

January 2006 – Potential Interference To Galileo From 23cm Band Operations by Peter Blair G3LTF
http://www.southgatearc.org/articles/galileo.htm