2.13 Part 13

1. Remember pronunciation of the following words

radar, target, coherent, coherence, unique, ambiguity, magnetron, microwave, susceptible.

2. Read the words, pay attention to stress shift

production — productivity; volume — volumetric; simple — simplicity; operate — operational; transmit — transmission; able — ability; magnet — magnetic; amplify — amplification; mature — maturity; necessary — necessity; complex — complexity.

2.13.3 Remember the terms

coherent radar — когерентная PJIC (радиолокационная станция)

detection — обнаружение; детектирование

search — поиск, обнаружение

tracking — сопровождение (целей)

space — космос, космическое пространство

maturity — зрелость

ground mapping — картографирование

returns — отраженные сигналы

fire control — управление огнем (зенитных орудий и ракет)

volumetric search — объемный поиск

amplifier tube — усилительный электронный прибор

range — velocity — дальность — скорость

ambiguity — неопределенность

power handling ability — большая мощность

coded signals — кодированные сигналы

matched radar system — согласованная система PJIC

jamming — умышленная помеха

staggered — переплетенные

jittered — флуктуирующие

2.13.4 Find Russian equivalents to the English words

maturity

returns

tracking

coded signals

volumetric search

jamming

ground mapping

matched radar system

power handling capacity

amplifier tube картографирование кодированные сигналы большая мощность согласованная система РЛС отраженные сигналы усилительный электронный прибор сопровождение целей умышленная помеха зрелость

объемный поиск

2.13.5 Find synonyms, translate them

sophisticated a, restrict v, velocity n, obtain v, vary v, surpass v, determine v, change v, mean v, common a, techniques n, solve v, signify v, speed n, get v, overcome v, de­fine v, complicated a, conventional a, substitute v, limit v, replace v, decide v, methods n.

2.13.6 Find antonyms, translate them

receiver n, move v, sophisticated a, increase v, necessary a, considerable a, with prp, unnecessary a, decrease v, without prp, negligible a, transmitter n, simple a, stop v.

2.13.7 Find Russian equivalents to the English words

радар код

детектирование, обнаружение

никальный

риск

эмиттер

атмосфера

импульс

фаза

atmosphere

radar code

detection

phase risk

emitter unique information pulse

информация, сведения

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

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

techniques. The ability to distinguish between successive pulses emitted by the transmitter also can be used to overcome range-velocity ambiguity restriction.

Notes to the text

range velocity ambiguity restriction — неопределенность в определении дальности по скорости

signal to noise ratio — отношение сигнала к шуму rather than — а не

noise pulse repetition periods — импульсно-шумовые периоды повторения counter measure deception techniques—счетно-измерительные маскировочные методы