- •Учреждение образования «высший государственный колледж связи» «чтение и перевод технических текстов по специальности ткс»
- •Часть I
- •Введение
- •Unit 1 (17) Antennas
- •17.1 Types of antennas
- •17.1.1 Antennas used in communications
- •17.2 Basic properties
- •17.3 Generic antenna types
- •17.3.1 Radiation from apertures
- •1 Learn the words & word combinations:
- •2 Read & translate the text (orally) 17.1 – 17.3.2:
- •5 Answer the questions:
- •17.3.2 Radiation from small antennas
- •17.3.3 Radiation from arrays
- •17.4 Specific antenna types
- •17.4.1 Prime focus symmetric reflector antennas
- •17.4.1.1 Parabolic reflectors
- •17.4.1.2 Aperture fields and radiation patterns
- •17.4.1.3 Gain of reflector antennas
- •1Learn the words & word combinations:
- •2 Read & translate the text (orally) 17.3.2 – 17.4.1:
- •5 Answer the questions:
- •17.4.2 Dual symmetric reflector antennas
- •17.4.3 Offset reflectors
- •17.4.4 Horn feeds for reflector antennas
- •17.4.4.1 Rectangular or square horns
- •17.4.4.2 Small conical horns
- •17.4.4.3 Multi-mode conical horns
- •17.4.4.4 Conical corrugated horns
- •17.4.4.5 Array feeds
- •1 Learn the words & word combinations:
- •2 Read & translate the text (orally) 17.4.2 – 17.4.4:
- •5 Answer the questions:
- •17.5 Antennas used in communication systems
- •17.5.1 Microwave line of sight radio
- •17.5.2 Earth station antennas
- •1 Learn the words & word combinations:
- •2 Read & translate the text (orally) 17.5.1 – 17.5.2:
- •5Answer the questions:
- •17.5.3 Satellite antennas
- •17.5.3.1 Telemetry, tracking and command (tt&c)
- •17.5.3.2 Spot beams
- •17.5.3.3 Multiple beams
- •17.5.3.4 Shaped beams
- •17.5.4 Vhf and uhf communications
- •17.5.5 Hf communications
- •1 Write out the words and word combinations which are still unknown to you and learn them. Unit 2 (20) Frequency division multiplexing
- •20.1 Fdm principles
- •20.2 History
- •20.3 Fdm hierarchy
- •20.3.1 General considerations
- •20.3.2 Channel bandwidth
- •20.3.3 Group and supergroup
- •20.3.4 Higher order translation
- •20.3.4.1 15 Supergroup assemblies
- •20.3.4.2 Mastergroup
- •20.3.4.3 Bell system
- •1 Learn the words & word combinations:
- •2 Read & translate the text (orally) 20.1 – 20.3.4:
- •4Find English equivalents:
- •5 Answer the questions:
- •20.4 Frequency translation
- •20.4.1 Ring bridge modulator/demodulator design considerations
- •20.4.1.1 Carrier compression.
- •20.4.1.2 Carrier and signal suppression
- •20.5 Carriers
- •20.5.1 Carrier frequency accuracy
- •20.5.2 Carrier purity
- •20.5.3 Carrier level
- •20.6 Pilots
- •20.6.1 Translation equipment pilots
- •20.6.1.1 Use of reference pilots for automatic gain control
- •20.6.2 Line equipment pilots
- •20.6.2.1 Regulation pilots
- •20.6.2.2 Frequency comparison pilots
- •1 Learn the words & word combinations:
- •2 Read & translate the text (orally) 20.4 – 20.6
- •5. Answer the questions:
- •20.7 Noise contributions
- •20.7.1 Definitions
- •20.7.2 Psophometric weighting
- •20.7.3 Thermal noise
- •20.7.4 Noise due to unlinearity
- •20.7.4.1 Single channel load
- •20.7.4.2 Multichannel load
- •20.7.4.3 Unlinearily characterisation
- •20.7.4.4 Determination ofunlinearity noise from a multichannel load
- •20.7.4.5 Approximate value for the weighted intermodulation noise contribution
- •20.7.4.6 Weighted noise power in pWOp
- •20.7.4.7 Determination of unlinearity noise using spectral densities
- •1 Learn the words & word combinations:
- •2 Read & translation the text (orally) 20.7:
- •5 Answer the questions:
- •20.8 Measurement of noise contributions
- •20.9 Overload
- •20.9.1 Overload measurement.
- •20.9.1.1 Harmonic/intermodulation products
- •20.9.1.2 Gain change
- •20.10 Hypothetical reference system
- •20.10.1 Noise contributions
- •20.10.2 Line sections
- •1 Learn the words & word combinations:
- •2 Read & translate the text (orally) 20.8 -20.10:
- •5 Answer the questions:
- •20.11 Companding
- •20.11.1 Compander characteristics
- •20.11.2 Multichannel load increase
- •20.11.3 Compandor noise advantage
- •20.13 Transmultiplexers
- •20.13.1 Synchronisation
- •20.13.2 Pcm alarms
- •20.14 Repeatered cable line equipment
- •20.14.1 Pre-Emphasis
- •20.14.2 Thermal noise
- •20.14.3 Regulation
- •20.14.3.1 Regulation range
- •20.14.4 Power feeding
- •Translate the text 20.11 – 20.14.4
- •Translate in written form point 20.13 “Transmultiplexers”
- •«Чтение и перевод технических текстов по специальности ткс»
- •Часть I
20.6.2 Line equipment pilots
Specific pilots are combined with the traffic path for transmission over copper line systems.
20.6.2.1 Regulation pilots
Regulating pilots are placed at the high end of cable frequency spectrum close to the top traffic frequency where the cable loss is greatest and the pilot most sensitive to any loss changes. The gain of the line repeater is modified to keep the pilot level constant throughout the seasonal changes of cable loss and thus the traffic power level at the repeater output can be maintained close to the thermal and intermodulation noise design optimum. The regulating pilot is transmitted at-lOdBmO. (See also Section 20.14.3.)
Commonly used regulating pilot frequencies are given in Table 20.4.
20.6.2.2 Frequency comparison pilots
The frequency comparison pilot is used at each translation point to maintain the carrier generation master oscillators to a high degree of frequency stability. The pilots are placed at the low end of the cable frequency spectrum for minimum phase error shifts. These phase shifts occur from the cable and equalisers. Some commonly used frequency comparison pilots are given in Table 20.5.
1 Learn the words & word combinations:
ring modulator |
кольцевой модулятор |
bridge ring modulator |
мостовой кольцевой модулятор |
forward bias |
напряжение прямого смещения |
signal path |
такт сигнала |
square wave |
прямоугольное колебание |
circuit constant |
постоянная цепи |
output frequency |
выходная частота канала |
waveform |
форма волны |
Odd harmonics |
Нечетная гармоника |
Baseband signal |
Модулирующий сигнал |
Transmission path |
Канал передачи |
AGC (automatic gain control) |
Автоматическая регулировка усиления |
Distortion |
Искажение |
Time constant |
Постоянная времени |
Intermodulation noise |
Межмодуляционный шум |
Phase shift |
Фазовый сдвиг |
Equalizer |
Выравниватель |
Thermal noise |
Тепловой шум |
(un) linearity |
(не) линейность |
Reference point |
Опорная точка |
Wire(ing) point |
Монтажная точка, место присоединения |
Entity |
Сущность, категория |
Switchpoint |
Точка коммутации, коммутационный узел |
Test signal |
Испытательный сигнал |
2 Read & translate the text (orally) 20.4 – 20.6
3 Find Russian equivalents:
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4. Find English equivalents:
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