🔍 Key Concepts

• Inmarsat-C uses L-band frequencies in the 1.5–1.6 GHz range for shipboard terminals • The ship’s "reception" is the satellite-to-ship (downlink) direction, and "transmission" is ship-to-satellite (uplink) • In mobile-satellite services, the uplink is usually at the higher frequency band than the downlink

💭 Think About

• Which ranges in the choices look like general L-band allocations, and which look like the narrower sub-band typically assigned to Inmarsat-C? • Remember that mobile-satellite services often have downlink around 1.5 GHz and uplink around 1.6 GHz – how does that help you pair reception vs transmission? • Two of the options are identical – what does that tell you about how carefully you must check the numerical limits and the order of reception/transmission?

✅ Before You Answer

• Confirm which side (ship or satellite) is associated with the higher L-band frequencies (~1.6 GHz) • Check whether Inmarsat-C is defined over the full allocation band or a more limited segment within it • Verify that the reception band you choose is consistent with the usual downlink (satellite-to-ship) direction for Inmarsat services