A.20KM B.50KM C.100KM
A.SDH系統(tǒng)中譯碼是將加擾NRZ碼解擾,而PDH系統(tǒng)中將5B6B,8B1H等碼譯為PCM電端機(jī)的CMI和HDB3碼 B.SDH,PDH都是將擾碼NRZ碼解擾 C.SDH譯碼是將5B6B,8B1H碼譯為CMI和HDB3碼
A.正弦波 B.余弦波 C.矩形脈沖