在进行POE链路预算时，已知光纤线路长5km，下行衰减0.3dB/km；热熔连接点3个，衰减0.1dB/个；分光比1∶8；衰减10.3dB；光纤长度冗余衰减1dB。下行链路衰减的值是（ ）。
- A.11.7d
- B.13.1dB
- C.12.1
- D.10.7
正确答案及解析
正确答案
B
解析
下行链路衰减：5×0.3+3×0.1+10.3+1=13.1dB。
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