RES425 – 323 – recognizing a) that ICAO develops Standards and Recommended Practices (SARPs) for systems enabling position determination and tracking of aircraft; b) that Annex 10 to the Convention on International Civil Aviation contains SARPs for terrestrial ADS-B usage of the frequency band 1 087.7-1 092.3 MHz, noting that the development of performance criteria for space station reception of ADS-B operating under the provisions of No. 5.328AA, including whether such criteria would require modifications to ICAO standard ADS-B equipment, is the responsibility of ICAO, resolves 1 that the use of the frequency band 1 087.7-1 092.3 MHz by AMS(R)S systems shall be in accordance with recognized international aeronautical standards; 2 that AMS(R)S systems (Earth-to-space) in the frequency band 1 087.7-1 092.3 MHz shall be designed so that they can operate in the interference environment as described in considering c); 3 that, taking into account resolves 2, AMS(R)S use of the frequency band 1 087.7-1 092.3 MHz shall not constrain administrations which have responsibilities as referred to in considering h), invites the ITU Radiocommunication Sector to complete, as a matter of urgency, the studies related to the space station reception of ADS-B in the frequency band 1 087.7-1 092.3 MHz, further invites the International Civil Aviation Organization to continue to participate in the studies, instructs the Secretary-General to bring this Resolution to the attention of ICAO and communicate the results of the studies when available.