锛?鍚岃酱浼犺緭绾挎槸涓?浼樿川瀹藉甫灞忚斀浼犺緭绾?br />
[Quality]: transmission attenuation.
[Broadband]: Now the level of our products have achieved 0 ~ 20Gz; twisted pair coaxial transmission bandwidth is about 1 / 10;
[灞忚斀]锛氬畠鎶婁紶杈撲俊鍙风殑鐢电鍦哄叏閮ㄩ檺鍒跺湪灞忚斀灞傚唴閮紝涓嶅悜澶栬緪灏勶紝鏍规嵁鏀跺彂鍙?鍘熺悊锛屽鐣岀數纾佸満涔熶笉鑳界┛杩囧睆钄藉眰杩涘叆鍐呴儴銆?br />
The principle of coaxial interference produced is another matter, twisted pair is different, its signal transmission electromagnetic field theory is distributed in infinite space. Reversible under the principle of sending and receiving, the external electromagnetic field can also go directly to twisted pair. Twisted pair can not prevent external electromagnetic field to enter, but with a helical twist of the way, so that two lines of the received signal, "exactly the same as far as possible", and a balanced differential signal processing technology, the same as that of "common-mode signal "restrain out. The key here is the twisted pair of "balance" feature, "balance" when there are differences, interference can take advantage of the external object will also affect the balance. Project on "balance" is relative, not absolute, the circuit's "common mode rejection" has a range of performance. These two practical problems, determine the twisted pair of anti-interference ability is limited, the integration of network cabling in the Rules strong interference case, you must use shielded twisted pair, is the truth.
2. Coaxial and twisted pair transmission characteristics is provided by the national standard, can not change. Such as video signals on top band for the 6M, the 2000 meters transmission distance, SYWV-75-5 cable attenuation of 40db, the voltage decay 100 times, 1Vp-p video signal attenuation of 6M to 10mv, or 80db microvolts, in this level video resume, you can ensure high SNR. Experience with the cable system design engineers, is very clear; for unshielded twisted pair, 2km of 6M attenuation of 92db, attenuation of nearly 4 times higher than 75-5 coaxial large 52db (400 times);
3. Twisted pair 2km, 1Vp-p signal attenuation to 25 micro-volts, that level is 28db microvolts, and the circuit has the noise level can be close, only the end of the compensation signal to noise ratio will seriously deteriorate the way out can only enhance the front-end level.杩欏氨鏄洰鍓嶅弻缁炵嚎浼犺緭蹇呴』閲囩敤鐨勨?鍓嶆帹鍚庢媺鈥濇妧鏈柟妗堬紝瑕佹眰鍓嶅悗璁惧鐨勮ˉ鍋挎彁鍗囨?鑳藉姏蹇呴』澶т簬92db,瀹為檯搴旇鍋氬埌100db銆?Now I only see a manufacturer provides a 60db capacity building of the data, do not know is that the frequency data. Also to note, front-end large-signal amplification to enhance the inherent noise generated by the circuit itself, than the end of the small-signal circuit intrinsic noise generated by much larger, faster deterioration of the system signal to noise ratio, it was suggested that twisted pair transmission equipment relay relay series can do a lot (a lot more than the coaxial), which is entirely ignorant of the imagination, theory and practice are not justified;
Conclusion: Comparing the coaxial and twisted pair transmission system, two points must be seized: one more difference between transmission characteristics of two lines, the second is to look at the performance level and transmission equipment.
相关链接:
"Dragon Century: The Origin of" Game of the background Qunari people
Easy Online Gaming
3G2 To MOV
China's own 3G licenses will be ready to go from the TD-SCDMA
MKV to MP4
android widget review curvefish onoff
Zhongguancun Hand new countryside
RMVB to MP4
Miao QINGHAI: Digital Agriculture Discussion
B2G Appeared In China Yiwu Fair Into The White House
Liu Yunjie Chinese Academy Of Engineering: "Soft Exchange Untimely"
Dell is holding a 10 billion U.S. dollars in cash ready to deal
VS 2008 and. NET 3.5 Beta2 introduce new Features
Easy Graphic
Superstar format -> BMP
Comment Web Servers
No comments:
Post a Comment