電線電纜網(wǎng) > 通訊電纜 > IEC 61156-5 為什么找不到NEXT標(biāo)準(zhǔn)公式?（完整版）
IEC 61156-5 為什么找不到NEXT標(biāo)準(zhǔn)公式? - 無(wú)圖版
xyjilo --- 2012-10-29 15:01:43
1
如題,只有功率合公式,沒(méi)有找到NEXT公式,請(qǐng)問(wèn)哪里有?
h20050967 --- 2012-10-29 15:33:04
2
IEC 61156-1有，NEXT=10LOG10(P1N/P2N),知道公式，也沒(méi)有太多實(shí)際作用
Beltriem --- 2012-10-31 09:06:06
3
原文如下：
The worst pair power sum near-end crosstalk, PS NEXT, at all frequencies, f, in the frequency range indicated inTable 6 shall not be less than the value abtained from Equation (6) useing
PS NEXT(f)=PS NEXT(1)-15*log10(f) (6)
For those frequencies where the calculated value of PS NEXT is greater than 75 dB,the requirement shall be 75 dB.
The minimum pair-to-pair NEXT for any pair combination shall be at least 3 dB better than the PS NEXT for any pair.