🔍 Key Concepts

• Marine RADAR antenna construction on merchant ships • Difference between waveguide arrays, parabolic dishes, and simple dipoles • Which antenna type produces the narrow horizontal beam and wide vertical beam typical of shipboard RADAR

💭 Think About

• When you look at a commercial ship’s RADAR from the dock, what does the antenna actually look like? A dish, a bar, or a simple rod? • Which of these options is commonly used to create a long, thin beam that sweeps 360° in azimuth but has a broad vertical coverage? • Think about which of these designs is rugged, simple, and commonly seen on merchant vessel bridges and masts rather than on high‑end military systems.

✅ Before You Answer

• Picture the physical shape of standard merchant‑ship RADAR antennas you’ve seen in photos (often a long horizontal ‘bar’). • Eliminate any options that are more typical of satellite TV dishes or basic radio antennas rather than marine RADAR. • Ask yourself which design best fits a long rectangular radiator with slots along its length, used to form the scanning beam.