1. WRC Resolution 205
First results of 406 MHz Monitoring programs

2. 406 Mhz Monitoring program
Introduction
France presented document FM22(16)51 during FM22 meeting (October 2016). WRC Resolution 205 (rev 2015) calls for the organisation of monitoring programmes in the adjacent bands and MHz around the MHz MSS band dedicated to search and rescue by satellite (COSPAS SARSAT system).
A drafting group was formed to define the monitoring activities required from administrations to satisfy this request and to define to process to set up monitoring campaign.
This document presents the French contribution to the 406 MHz monitoring program
22 fixed spectrum control stations were used to conduct these measurements

3. Location of fixed stations
406 Mhz Monitoring program
Location of fixed stations

4. 406 Mhz Monitoring program
Equipment
THALES TRC8021, TRC8025 and MRE type Esmeralda receivers
THALES Spectrum Monitoring System
Rohde & Schwarz EB110, EM100 and EM550 measuring receivers
Spectrum detection and recording software "IRIS“(ANFR developed software) and R&S "Ramon“
The measurements were carried out from the remote stations of our national spectrum control system. A surveillance was also conducted from laboratory vehicles.

5. Detection threshold (dBµV)
406 Mhz Monitoring program
Methodology
The observation period extends from December 2016 to March 2017.
The observation was not continuous as a result of the use of the spectrum monitoring system for other purposes.
Frequency band scans have been launched through the use of stand-alone programs over periods of two days of scrutiny and two days of analysis of results.
A reconciliation of the results was carried out against data from our data bases to determine the status of the detected emissions.
Research and location using stationary and mobile location systems for unknown emissions was not triggered during this measurement campaign
The step frequency (12.5 kHz) is in line with the transmissions currently in operation under the fixed and mobile services, especially in the upper adjacent band
Frequency start (MHz)
Frequency end (MHz)
Step (kHz)
Detection threshold (dBµV)
Modulation
AFC
405.9
406.2
12,5 -5 FM No

6. 406 Mhz Monitoring program
Preliminary results
405.9 MHz MHz : this is the lower adjacent band and only one emission detected on MHz was detected (Dijon region).
406 MHz – MHz : this is the search and rescue band. Therefore, depending on the visibility of the reception, it is possible to find emissions corresponding to true Cospas-Sarsat emissions. In fact, several emissions were detected, and they are characterized by impulses of a few hundred microseconds and are repeated only a few times a week. Their location seems difficult because of very low frequency detection and very short duration.
406.1 MHz – MHz : this is the upper adjacent band and several emissions were detected on the frequency of MHz corresponding to authorized regulated emissions. It appears that these levels found in this frequency band are very low. Unknown azimuths are the result of mobile emissions or radio direction-finding errors.

7. 406 Mhz Monitoring program
Conclusion, Proposals
It is expected that detections will be seen using terrestrial monitoring stations means. In Europe, detections will been seen especially in the upper adjacent band “406.1 – MHz” due to authorized frequency assignments.
It is therefore essential to continue the work initiated by the Working Group set up during the previous FM22 to verify that no new frequency assignments will be done and unauthorized emissions will appear within the frequency bands MHz and MHz under the mobile and fixed services.
Later, it will allowed to evaluate the impact of emissions from systems operating in the frequency bands MHz and MHz on MSS reception in the frequency band MHz and to assess the effectiveness of this resolution.

8. 406 Mhz Monitoring program
Conclusion, Proposals
The comparison of the results of measurements made by FM22 members will be helpful to finalize a unified process to conduct measurement campaigns.
Eventually, a unified format for the transmission of the results of these measurement campaigns will be defined.
Administrations are kindly invited to provide a plan for future measurement campaigns.
In addition, France has the intention to draft an input to the next ITU-R WP1C meeting in June with a view of revising existing ITU-R Recommendation SM (Priority of identifying and eliminating harmful interference in the band MHz). The existing part dealing with in-band interference will be kept, and an added annex in connection with the monitoring in adjacent bands will be added (the two aspects of monitoring using terrestrial and satellite means will be introduced).

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