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TERRESTRIAL MICROWAVE COMMUNICATIONS SYSTEMS

In document BOOK_REVIEW_-_BLAKE.pdf (Page 79-87)

1.  A single transmission path from transmitter to receiver. Hop 2. The signal-to-noise ratio in a receiver at a point before the

detector. Carrier-to-noise Ratio

3. The deviation of a wave as it passes an obstacle or passes

through a small aperture. Diffraction 4. It is the use of more than one frequency or transmission

path to improve system reliability in the presence of fading. Diversity 5. It is the energy received in the time taken to transmit one

bit. Energy per Bit

6.  Variation in received field strength over time due to

changes in propagation conditions. Fading 7.  A region near an object in which diffraction effects are

significant. Fresnel Zone

8. It is the abrupt variations in the timing of a digital signal. Jitter 9. It is a network using microwaves for two-way transmission

for telephony, television, and high-speed data.

Local Multipoint Distribution System (LMDS)

10. This is a terrestrial microwave system for the distribution of television, Internet, and telephone services to businesses and residences.

Multichannel Multipoint Distribution System (MMDS) 11. A receiver-transmitter combination that amplifies and

transmits a signal. Repeater

12. A map showing surface features, including the elevation of

the terrain. Topographic Map

13. Terrestrial microwave links generally use ______________

propagation. Line-of Sight (LOS)

 Attenuation due to rain, Ducting,

 Aging or partial failure 15. Fading due to multipath reception can reduce the received

signal strength by ______ or more. 20dB 16. This technique is done by slightly changing the frequency

so that the phase difference between the direct and reflected signals is no longer 180°.

Frequency Diversity

17. To protect against fading on a moment-to-moment basis, frequency diversity requires two transmitters and two receivers, better known as a _____.

Hot Standby

18. This technique is done by placing two antennas one above

and the other on the same tower. Space Diversity 19. Two systems of terrestrial microwave links.  Analog,

Digital 20. Analog system is also called ______ or _______.  AM System,

FM System 21. Digital system is also called _______. QAM System 22. Digital data can also be transmitted with FM systems using

 ______ ______. External Modems

CHAPTER 19: TELEVISION

1. Ratio of the width to the height of a television picture.  Aspect Ratio 2. The portion of the horizontal blanking pulse after the synch

pulse. Bach Porch

3. The video level corresponding to zero luminance. Black Setup 4. The period of time when the electron beam in a CRT is cut-

off. Blanking

5.  A vacuum tube that uses a moving electron beam to

produce patterns or images on a photophorescent screen. Cathode-ray Tube (CRT) 6. The color signal. Chrominance (Chroma) 7. These are several cycles of color subcarrier on the back

porch of the horizontal sync for color synchronization. Color Bursts 8.  A filter that can pass or reject a fundamental frequency and Comb Filter

its harmonics.

9.  A video system in which color and luminance are sent

separately, without frequency interleaving. Component Color 10. A video system in which luma, sync, and chroma signals

are combined. Composite Video

11. Alignment of the three electron beams in a color CRT so

that they land on the same triad of color phosphor dots. Convergence 12. the pulses in the vertical blanking interval of a video signal

that create interlaced scan. Equalizing Pulses 13. In an interlaced video system, it is one-half of a frame

consisting of alternate lines. Field 14. One complete image in a video system is called ________. Frame 15. The portion of horizontal blanking pulse before the sync

pulse. Front Porch

16. A television receiver design that uses mixing between the picture and sound carriers to generate the sound

intermediate frequency.

Intercarrier Sound

17. A video scanning system that divides a frame into two

fields to reduce flicker. Interlace 18. The signal that provides brightness information in a video

system. Luminance (Luma)

19. A North American television standard. NTSC Video 20. The video signal level representing maximum luminance. Peak White

21. Picture element. Pixel

22. A video system that does not use interlace. Progressive Scan 23. In a color CRT, it is the adjustment of the three electron

beams so that each lands on phosphor dots of the appropriate color.

Purity

24. The pattern of scanning lines in a video system. Raster 25. The amount of detail produced by a video system. Resolution 26. The return of the electron beam in a CRT from right to left

or from top to bottom. Retrace

27. A color video system in which the three primary colors are

transmitted separately. RGB Color 28. The main accelerating element in a CRT. Ultor

be used in determining vertical resolution.

30. A specialized oscilloscope designed for the observation of

composite color signals. Vectorscope 31. The assembly that contains the deflection coils and is

mounted on the neck of a CRT. Yoke 32. The North American NTSC television system transmits ___

frames per second. 30

33. Each frame transmitted by NTSC consists of _______ lines. 525 34. The NTSC uses a _______ interlace so that ______ fields

are transmitted per second.

2:1, 60 35. Composite color video uses two color signals modulated on

a subcarrier at 3.58 MHz using _________ ________. DSBSC QUAM 36. Terrestrial television broadcasting uses a channel _______

wide. 6 MHz

37. The picture in terrestrial television broadcasting is

transmitted using _______ with carrier. VSB AM 38. The sound in the terrestrial television broadcasting uses

 ___ on separate carrier to the video. FM 39. Picture and sound travel together through the _____ and

 ___ ______ of a television receiver.

Tuner,

Picture IF Sections 40. The sound is converted to a separate 4.5 MHz IF, in a

system known as __________ _________. Intercarrier Sound 41. Color receivers use _______ _________ to retrieve the

color signal. Synchronous Demodulation 42. The frequency and phase reference for the color

demodulators are provided by a ________ _______ on the back porch of the horizontal synchronizing signal.

Color Burst

43. The CRTs used in television receivers generate an

 ________ ______ that is intensity-modulated by the video signal and deflected horizontally and vertically by coils that surround the tube.

Electron Beam

44. Color CRTs use three electron beams striking three different types of phosphors that glow ____, ____, and  ______.

Red, Green,

Blue

45. It reduce losses by moving UHF signals to the VHF range. Cable-television System 46. It is a technique used for reducing flicker on frame rates of Interlaced Scan

25 or 30 Hz..

47. Two time intervals. Horizontal Blanking Interval, Vertical Blanking Interval 48. The three primary colors that are mixed to achieve good

color reproduction.

Red, Green,

Blue

49. Two other standards of color television.

Phase Alteration By Line (PAL), Sequential Color and Memory

(SECAM) 50. The television stereo sound system is called ___________

 _____ _________. Multichannel Television Sound

51. The first CRT. Monochrome CRT

52. In order to reproduce the three primary colors of the color television system, a color CRT must have _______ electron beams.

Three (3)

In document BOOK_REVIEW_-_BLAKE.pdf (Page 79-87)

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