communication engineering practice report essay

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time flies, in their first year university life is coming to an end. A year's time, I learned a lot, also got a lot of students as learning, communication engineering specialty, as will soon become a communication students,christian louboutin uk, understand the basic knowledge of communication,air jordan, learning to master professional communication,christian louboutin outlet, understand the forefront of communication industry science and technology knowledge, is related to their future, in relation to can you realize the life value of life. The
one one years, through eight weeks short "communication",louboutin pas cher; learning,louboutin, usually through their own magazine, newspaper, network knowledge, and two weeks of teacher, professional lectures, as well as in the China Unicom (Daqing branch), Daqing Petroleum Institute telephone station visit,air jordan pas cher. The communication based on my knowledge of the sort, summarize, in order to learn in the future life, work, system to make better use of these resources.

a teacher lectures, optical communication
1876 years the United States Belle after the invention of the telephone, telephone research has become a new topic of many scientists, factors affecting the telephone was born: a meteorological conditions are stable transmission of optical media C to find the ideal light source.
is known as the ",louboutin outlet;father of optical fiber communication" Kao (British Chinese), in the study of optical telephone made significant contribution, in the medium, reducing impurity Ma Rui,louboutin pas cher, card spectrum uplift, Keck will reduce noise to 20 dB / km in 1070, even more exciting is the 2 fundamental problems solve the photoelectric produced on the invention of semiconductor laser can produce the ideal light source.
1974 light impurity noise to 1 dB / km. In 1979 reduced to 0. 2 dB / km. In 1977 the United States Chicago and Santa Monica between grinding was first built commercial optical fiber communication system, fiber glass hair thickness can also opened 8000 telephone,jordan pas cher.
to the development of optical fiber communications in 1990 made significant progress: 1 by multimode fiber to the single mode (only one mode, no dispersion, transmission bandwidth, the amount of information sent more than multimode fiber by short wavelength (0) 2. 85 microns) to the long wavelength (1. 31 microns),red bottom shoes. 90 in the optical fiber transmission rate of up to 10000000000000000 bits per second. The hair is equivalent to the 1/10 fiber can be opened at the same time 1250000 phones. Optical communication every few kilometers, add a ",christian louboutin outlet;regenerative repeater" (? ? light electric light) to increase the signal transmission, the 1985 "doped Er fiber amplifier",air jordan; was born.
light gourd communication: the light pulse broadening, narrowing of the two effects cancel each other, became a keep constant light gourd.
our fiber development: 1977 was the first wavelength (0. 85 microns) step to fiber, >