高h纯肉大尺度调教play,少妇被又大又粗又爽毛片,国产熟女亚洲精品麻豆,精品少妇无码av无码专区

industry news

The Present Situation and Future Development and Application of Optical Fiber Communication

author:admintime:2019-09-22 22:08click:
            Light is everywhere. In the early days of human development, light has been used to transmit information. But at that time, the information capacity was very small and the limitations were very large.
            With the development of society, the amount of information transmission and exchange is increasing day by day. The traditional way of telecommunication can not meet people's needs. In order to expand the communication capacity, the communication mode has developed from medium wave and short wave to microwave and millimeter wave, which in fact expands the communication capacity by increasing the carrier frequency of the communication. In this way, the present optical communication technology is optical fiber communication.
            Optical fiber communication is a communication mode which modulates the image, data and other signals to be transmitted to the optical carrier and uses optical fiber as the transmission medium.
            Compared with traditional telecommunications, optical fiber communication uses high frequency light wave as carrier and optical fiber as transmission medium. Because of the advantages of low loss, wide transmission bandwidth, large capacity, small size, light weight, anti-electromagnetic interference, and not easy to cross talk, optical fiber communication has been favored by the industry since its emergence and developed very rapidly. The transmission capacity of optical fiber communication system has increased nearly 10,000 times since 1980, and the transmission speed has increased about 100 times in the past 10 years.
            Development and Application of Optical Fiber
            In order to develop optical communication technology, people have considered and tried various transmission media, but their losses are very high. Until 1966, Chinese-American Dr. Gao Rong and Dr. Hockham published papers predicting that low-loss optical fibers could be used in communications, opening the door to optical communications.

Telephone

0769-85415700

function

Price

quality

service

Wechat sweep

Mobile phone sweep

欧美丰满少妇xxxxx| 人妻丝袜无码国产一区| 永久免费av在线观看| 亚洲色偷偷偷网站色偷一区| 国产精品夜间视频香蕉| 精品麻豆国产色欲色欲色欲www| 国产麻豆成人传媒免费观看| 被灌满精子的少妇视频| 欧美a级毛欧美1级a大片免费播放| 欧美国产日韩亚洲中文| 男女做爰猛烈吃奶啪啪喷水网站| 精品久久久久久无码人妻蜜桃| 国产xxxx做受视频| 精品国产一区二区av片| 扒开双腿吃奶呻吟做受视频| 成人网站精品久久久久| 亚洲av无码乱码在线观看性色| 日本19禁啪啪吃奶大尺度| 国产精品美女久久久久av爽李琼| 欧洲熟妇色 欧美| 国产精品成人无码免费| 国产超级va在线观看视频| 国产香蕉尹人在线观看视频 | 激情内射人妻1区2区3区| 无码区日韩特区永久免费系列| 中文字幕精品亚洲无线码二区| 国内精品伊人久久久久av| 青青草原精品99久久精品66| 午夜性爽视频男人的天堂 | 精品亚洲一区二区三区在线观看| 婷婷俺也去俺也去官网| 亚洲中文字幕琪琪在线| 日韩一区二区在线观看视频| 天天摸夜夜摸夜夜狠狠添| 久久这里只有精品18| 日韩精品免费一线在线观看| 国产男女无遮挡猛进猛出 | 亚洲成av人片在www色猫咪| 亚洲日韩精品一区二区三区无码| 精品乱码久久久久久中文字幕| 亚洲欧洲美色一区二区三区|