My speciality. Овчинникова Т.Е - 39 стр.

      2.13.7 Find Russian equivalents to the English words

atmosphere                  радар
radar                        код
code                        детектирование, обнаружение
detection                   никальный
phase                       риск
risk                        эмиттер
emitter                     атмосфера
unique                      импульс
information                 фаза
pulse                       информация, сведения

      2.13.8 Anylise the second sentence (paragraph 1). Define types of
attributive clanses

      2.13.9 Read a questions for each paragraph, find answers in the text

1. Where did coherent radars generally continue to be used during the past years? 2.
How many operations are necessary to determine the Doppler shifts in the frequency
of the returns? 3. In what way do microwave power amplifier tubes surpass
magnetrons? 4. What is a common characteristic of a new radar?

          RADAR AND RADIO NAVIGATION COHERENT RADAR

1. During the past years, coherent radars generally continued to be used in ground-
mapping, detection of moving targets on the ground, and search and tracking in the
atmosphere and in space. This shows the degree of maturity these sophisticated systems
have achieved, but it does not mean that all their problems have been solved.
2. Two operations are necessary to determine the Doppler shifts in the frequency of
the returns for obtaining velocity information and to improve the signal-to-noise ratio
in volumetric search and fire control radars.
3. There has been a resurgence of interest in techniques for obtaining coherence with
radars using magnetron transmitters rather than microwave power amplifier tubes.
Mention should be made that these tubes surpass magnetrons in both efficiency and
power handling ability, but they are still very expensive and a radar using a chain of them
is quite complicated. If coherence can be achieved with magnetron transmitters,
coherent radars will be considered for application in which cost and simplicity are
primary factors.
4. A common characteristic of a new radar is the increased use of coded signals and
of detection systems for decoding in the receiver. The result is known as a "matched"
radar system. The coding can vary in complexity from staggered, jittered or noise
pulse repetition periods to true coding of each pulse by changes of frequency or phase
within the pulse. It makes each radar transmission more clearly unique, so that there is
less risk of the receiver confusing the returns with other signals. The system thus
becomes less susceptible to noise, jamming, and counter measure deception