What are the directional characteristics of...

Question 1 / 27070DwwroLuX9wEXqOSOOi7F

Question 1 of 27070DwwroLuX9wEXqOSOOi7F

What are the directional characteristics of the INMARSAT-C SES antenna?

Question 1 of 27070

What are the directional characteristics of the INMARSAT-C SES antenna?

🔍 Key Concepts

• INMARSAT-C system design and why it is different from earlier INMARSAT ship earth stations (SES) • How antenna stabilization requirements depend on beam width and directionality • Typical radiation pattern needed so a ship can maintain satellite contact in all headings and normal sea states

💭 Think About

• Think about whether INMARSAT-C terminals are meant to be small, simple, and easy to install on many vessels, or large, mechanically stabilized systems. • Ask yourself: if the antenna’s beam were very narrow, what extra equipment or stabilization would be needed on a rolling, pitching ship? Does that match what you know about INMARSAT-C? • Consider whether INMARSAT-C needs to keep a constant lock on one satellite in a fixed sky position, or whether its coverage pattern should handle changes in ship heading without constant mechanical pointing.

✅ Before You Answer

• Verify whether INMARSAT-C uses a parabolic dish or a small, fixed antenna unit. • Check if the system description in your GMDSS materials says stabilized antenna required or no stabilization required. • Confirm whether the radiation pattern is described as omnidirectional, narrow beam, or wide beam with a preferred direction.

Question 1 of 27070

What are the directional characteristics of the INMARSAT-C SES antenna?

Highly directional parabolic antenna requiring stabilization.

Wide beam width in a cardioid pattern off the front of the antenna.

Very narrow beam width straight-up from the top of the antenna.

Omnidirectional .

Question 1 / 27070DwwroLuX9wEXqOSOOi7F

Question 1 of 27070DwwroLuX9wEXqOSOOi7F

What are the directional characteristics of the INMARSAT-C SES antenna?

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Question 1 of 27070

What are the directional characteristics of the INMARSAT-C SES antenna?