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3. Dish-shaped antenna that focuses radio waves to a point.
5. The array type where current distribution is uniform across all elements.
7. Type of antenna that uses reflector, driven, and director elements for directional radiation.
8. The impedance of a standard dipole antenna in free space.
10. The plane in which the radiation pattern of a Yagi-Uda antenna is measured.
12. Broadband directional antenna consisting of dipoles of different lengths.
13. The point at which impedance of an antenna matches that of the transmission line.
15. The part of an antenna that radiates or receives radio waves.
16. The ratio of the power radiated in a particular direction to the power radiated isotropically.
17. The angular width between the half-power points of the main lobe.

1. Antenna that consists of two half-wave elements folded back on each other.
2. The unit used to express antenna gain in logarithmic scale.
4. Antenna array in which elements are spaced a half-wavelength apart to achieve desired directivity.
6. A common reference antenna used for measuring gain.
9. Radiation pattern of a directional antenna is often represented on this type of graph.
10. A parameter that measures how well an antenna converts input power into radio waves.
11. The antenna most suitable for satellite TV reception.
12. The polarization of electromagnetic waves in a parabolic dish antenna is usually this type.
14. The region close to the antenna where the field strength varies rapidly.
17. An antenna that can operate over a wide range of frequencies.