🔍 Key Concepts
• INMARSAT-B uses higher bandwidth voice/data services and typically requires a mechanically steered, directional (parabolic) antenna aimed at the satellite.
• INMARSAT-C is a lower data‑rate messaging system that commonly uses a small, fixed, omni-directional antenna.
• Think about how antenna size and directionality (parabolic vs omni) usually relate to gain, complexity, and the need to track the satellite.
💭 Think About
• Which system (B or C) would more likely need a larger, mechanically steered, high‑gain antenna to support wideband services like voice and fax?
• Which system is designed for simple, low‑rate data and messaging, and so can use a smaller, fixed antenna that does not need to be steered?
• Look at each option and ask: does it correctly pair the high‑gain parabolic antenna with the higher bandwidth system, and the small omni antenna with the lower bandwidth messaging system?
✅ Before You Answer
• Make sure you correctly match directional/parabolic antennas with the system that needs higher gain and satellite tracking.
• Confirm that the system designed for simple, low‑rate messaging is described as having a small, omni-directional antenna.
• Eliminate any choice where the description of antenna size vs function (gain/bandwidth) does not make practical engineering sense.