题目

求助中译英第二部分
αc(z)=Ne-(α×z)-Nr(z) (2)
式中：αc(z)——局部耦合损耗,单位dB；Ne ——电缆输入端的电平,单位dBm；Nr(z) ——天线处的接收电平,单位dBm；α——电缆的衰减常数,单位dB/km；z——电缆输入端到天线处的距离,单位km.
测得的耦合损耗可由αc50和αc95两个典型值来表征,αc50耦合损耗指50%接收概率,即50%测得的局部耦合损耗小于该值；αc95耦合损耗指95%接收概率,即95%测得的局部耦合损耗小于该值.
在IEC61196-4和GB/T17737.4标准中,电缆长度至少要10倍于测量频率下的波长,同时为确保测量有效,必须要有足够的位置分辨率标准规定,在95%接收概率时,每半波长要进行10次测量来计算耦合损耗.因此耦合损耗的测量依靠人工是不可能实现的,必须借助计算机和自动测量系统.
本漏泄电缆耦合损耗自动测试系统（见下图）包括轨道车、伺服控制系统、信号源、接收机、天线和计算机程控系统等,可以完全满足同轴漏泄电缆耦合损耗的测试要求.

提问时间：2020-07-18

答案

杜绝机译,专业对口,请审阅
αc(z)=Ne-(α×z)-Nr(z) (2)
Where αc(z) is local coupling loss,dB; Ne is the power level,dBm; Nr(z) is the receiving level at the antenna,dBm; α is the attenuation coefficient,dB/km; z is the distance from the input end of the cable to the antenna,km.
The measured coupling loss can be characterized by two typical values,αc50 and αc95,αc50 refers to that the receiving probability of 50%,i.e.50% of the measured local coupling loss,is less than that value; αc95 refers to that the receiving probability of 95%,i.e.95% of the measured local coupling loss,is less than that value.
In IEC 61196 and GB/T 17737.4 standards,the cable length should be at least ten times of the wavelength at the measuring frequency,in the same time,in order to ensure the measurement to be effective it is necessary to meet the stipulation of enough position resolution,in the case of 95% receiving probability ten times of measurement should be carried out for each semi-wavelength so as to calculate the coupling loss.Therefore it is impossible to achieve the measurement of coupling loss by manpower,and it is necessary to rely on computer and automatic measurement system.
the coupling loss measurement system of leaky coaxial cable (see the following Fig.) consists of track handcart,serve control system,signal source,receiver,antenna,computer program controlled system,etc.and is fully able to meet the requirements for the coupling loss measurement of leaky coaxial cables.