【正文】 ? ? Shorebased maintenance (SBM)。 ? Locating and homing signals in the GMDSS are provided by radar beacons and EPIRBs. SART beacons are intended for use onboard survival craft and enable ships and aircraft engaged in a search and rescue operation to locate survivors using 9 GHz (3cm) radar. Most EPIRBs in current manufacture also incorporate some form of locating function – a SART can be included in InmarsatE EPIRB, and the COSPASSARSAT 406 MHz EPIRBs now provide for an additional transmission on MHz, which suitably equipped ships and aircraft can use as a homing signal. 2022 April GMDSS Services – Lecture 1 76/93 s SART A SART will transmit an alert that will create a series of dots on the radar display of a Search amp。 Pacific Ocean Region (POR). 2022 April GMDSS Services – Lecture 1 42/93 2022 April GMDSS Services – Lecture 1 43/93 2022 April GMDSS Services – Lecture 1 44/93 2022 April GMDSS Services – Lecture 1 45/93 2022 April GMDSS Services – Lecture 1 46/93 2022 April GMDSS Services – Lecture 1 47/93 2022 April GMDSS Services – Lecture 1 48/93 Unlike the Inmarsatsatellites, COSPAS/SARSAT satellites are not geostationary, but orbit the earth on a North/South and South/North path. 2022 April GMDSS Services – Lecture 1 49/93 2022 April GMDSS Services – Lecture 1 50/93 2022 April GMDSS Services – Lecture 1 51/93 Navigational sea areas (GMDSS areas) ? The GMDSS is based on the concept of using four marine munication sea areas to determine the operational, maintenance and personnel requirements for maritime radiomunications, viz: Sea area A1, Sea area A2, Sea area A3, Sea area A4 ? (remark: old maritime radiomunication system was based on the concept of using ship’s size to determine the requirements) 2022 April GMDSS Services – Lecture 1 52/93 2022 April GMDSS Services – Lecture 1 53/93 Sea Area A1 ? Within the radiotelephone coverage of at least one VHF coast station in which continuous DSC alerting is available. Such an area could extend typically 30~50 nautical miles from the coast station. 2022 April GMDSS Services – Lecture 1 54/93 2022 April GMDSS Services – Lecture 1 55/93 Sea Area A2 ? An area, excluding sea area A1, within the radiotelephone coverage of at least one MF coast station in which continuous DSC alerting is available. For planning purposes this area typically extends to up to 150 nautical miles offshore, but would exclude any A1 designated areas. In practice, satisfactory coverage may often be achieved out to around 250 nautical miles offshore. 2022 April GMDSS Services – Lecture 1 56/93 2022 April GMDSS Services – Lecture 1 57/93 Sea Area A3 ? An area, excluding sea areas A1 and A2, within the coverage of an Inmarsat geostationary satellite in which continuous alerting is available. This area lies between about latitudes 70186。 Search and Rescue Radar Transponder (SART). 2022 April GMDSS Services – Lecture 1 34/93 2022 April GMDSS Services – Lecture 1 35/93 2022 April GMDSS Services – Lecture 1 36/93 ?NBDP (narrow band direct printing radiotelegraphy) 2022 April GMDSS Services – Lecture 1 37/93 2022 April GMDSS Services – Lecture 1 38/93 s SART 2022 April GMDSS Services – Lecture 1 39/93 2022 April GMDSS Services – Lecture 1 40/93 Inmarsat, COSPAS/SARSAT, Emergency Position Indicating Radio Beacons (EPIRBs), Status Recordingsystem (STAREC). 2022 April GMDSS Services – Lecture 1 41/93 Communication by means of the geostationary Inmarsatsatellites extends in an area between 70 degrees latitude North and 70 degrees latitude South. The 4 Inmarsatregions: Atlantic Ocean Region West (AORW)。 ? A ship in distress can alert other ships in the vicinity by sending a DSC distress alert on VHF and MF, simultaneously if desired, and follow it up with a distress (MAYD