2.17 Therefore, the Working Group, being of the opinion that better protection could be sought for the 3 GHz band if there was a clearer SOLAS requirement for the carriage of a 3 GHz radar, drafted the modifications to regulation V/20 for consideration by the Chapter V Working Group.
2.18 The Working Group considered NAV 45/8/1 (United States) regarding radio spectrum reallocations which would be considered by the ITU World Radiocommunication Conference in May/June 2000 (WRC-2000) and which could adversely affect the safety of maritime navigation using global navigation satellite systems and 3 GHz. Additionally, handheld mobile-satellite telephones could interfere with GNSS systems
2.19 Being informed that COMSAR 4 had developed the IMO position to WRC-2000 (COMSAR 4/14, annex 6) and covered the above-mentioned matters, the Working Group was of the opinion that the IMO position should be expanded with some sentences from NAV 45/8/1 and invited the Sub-Committee to instruct the Secretariat to add the following:
.1 "If an air traffic control radar operating near a port were to operate in this band used by marine radars, ships entering that port would likely be prevented from using their 3 GHz radar. In that situation, ships would be limited to using 9 GHz radar only. In adverse weather conditions, 3 GHz radar has far superior performance compared to 9 GHz radar, and such a restriction on the use of radar could cause a hazard to navigation."
at the end of the second paragraph of Background under agenda item 1.6;
.2 "Additionally, mobile-satellite services currently using bands adjacent to that used by GNSS, particularly handheld satellite telephones used aboard ships, can cause interference to shipboard GNSS systems. The potential for interference from ship passengers using handheld satellite telephones to shipboard GNSS systems is significant."
at the end of Background under agenda item 1.9; and
.3 "Additionally, technical limits should be placed upon mobile-satellite systems using bands adjacent to 1559-1567 MHz to ensure no harmful interference occurs to global navigation satellite systems onboard ships."
at the end of "IMO position" under agenda item 1.9.
2.20 The Working Group noted NAV 45/INF.2 (Secretariat) informing on the action taken by the ITU-R Working Party 8B concerning a previous IMO liaison statement pointing out difficulties with a proposal to adopt more stringent (Category B) limits for spurious emissions for fixed VTS, as opposed to mobile, radars. WP8B had drafted an appropriate footnote but it was reported that the ITU-R Task Group 1/5 had not finally adopted the footnote, so this issue would be determined on a local basis by national authorities.
2.21 The Working Group noted the information provided by ICAO (NAV 45/INF.7) outlining an ICAO position on critical concern to civil aviation to be considered at WRC-2000 and was of the opinion that this position concurred with the IMO position on protection of the frequency bands for existing and future GNSS.
