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Методичка 5курс (1 часть).doc
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1. Put the words in the right order to make a sentence:

1. An, a, transducer, antenna, is, that, transmits, electromagnetic, or, receives, waves. 2. The, first, were, rudimentary, built, antennas, by, 1888, in, Heinrich Hertz 3. There, two, are, directional, fundamental, of, antenna, types, patterns. 4. A, a, the, Hertzian, not, antenna, presence, does, require, of, for, ground, its, operation. 5. Small, for, antennas, preferred, are, usually, convenience. 6. The, the, of, word, antenna, relative, is, to, to, wireless, apparatus, attributed, origin, Guglielmo Marconi.7. Antennas, its, are, any, radiotransmitter, in, order, electromagnetic, to, couple, electrical, connection, to, required, by, receiver, or, the, field.8. Resonant, be, resonant, expected, to, used, around, a, are, antennas, particular, frequency.9. Resonant, frequency, antenna, conductors, have, the, the, the, impedance, lowest, feedpoint, at.

2. Fill in the blanks with the following words:

the emitter, a transducer, wires, rod, conductor, transmission, an antenna, variations, types

1. An antenna is …that transmits or receives electromagnetic waves. 2. Hertz placed …dipole in the focal point of a parabolic reflector. 3. There are two fundamental …of antenna directional patterns 4. There are many …of antennas. 5. The bandwidth of …may be increased by several techniques. 6. The patch antenna consists mainly of a square … mounted over a groundplane. 7. The dipole antenna is simply two … pointed in opposite directions. 8. One example of antennas is the very common vertical antenna or whip antenna consisting of a metal …. 9. An antenna lead-in is the … line which connects the antenna to a transmitter or receiver.

3. Complete the following sentences using active vocabulary:

1. An antenna is a transducer that transmits or receives…2. Antennas are used in systems such as…3. Some of the first rudimentary antennas were built in 1888 …4. Small antennas are usually preferred for… 5. The bandwidth of an antenna may be increased by …6. The random wire antenna is simply a very long wire with… 7. The dipole antenna is simply two wires pointed in opposite directions arranged either… 8. A loaded antenna is an active antenna having an elongated portion of… 9. A Hertzian antenna is a set of terminals that does not require the presence of … 10. An antenna grounding structure is a structure for establishing …

4. Say if the following statements are true or false:

1. The first rudimentary antennas were built in 1888 by Clerk Maxwell. 2. An antenna is an arrangement only of more conductors. 3. There are three fundamental types of antenna directional patterns. 4. The bandwidth of an antenna may be decreased by several techniques. 5. A simple straight wire antenna will have a different polarization when mounted vertically, and one polarization when mounted horizontally.6. The parabolic antenna consists of a square conductor mounted over a groundplane. 7. The patch antenna consists mainly of an active element at the focus of a parabolic reflector to reflect the waves into a plane wave. 8. The isotropic radiator is a purely theoretical antenna that radiates only in one direction.