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煩請各位大大撥冗來幫我看一下這個題目吧! 題目如下: A digital communication system consists of a transmission line with 4 regenerative repeaters(excluding the last receiver). The communication environment and design of all receivers are identical. The channel has an ideal frequency response over 320MHz≦f≦325MHz. The modulation scheme is OQPSK with coherent detection and the channel noise is AWGN with No=10^-10W/Hz. (b)If the bit-error-rate of the whole system≦5*10^-5 is required, the minimum received Eb/No at each receiver is . (Note: It is required Eb/No=12.6dB for BFSK signal with coherent detection and Pb=10^-5. ) 解答為: 5*BER≦5*10^-5 BER≦10^-5 Eb/No=9.6dB 我的疑問在於,5*BER≦5*10^-5,畫底線的5是從哪裡來的?是從題目敘述中的 transmission line with 4 regenerative repeaters(excluding the last receiver)得 知的嗎?請各位大大幫我解答,感恩! -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 111.248.14.224
maxwellyann:上面PO文有誤,因為用word編輯的,問題如下↓ 02/15 13:11
maxwellyann:5*BER≦5*10^-5.左式的5是由那一串英文敘述出來的嗎? 02/15 13:12
wolf0000:發射端+四個repeater,總共會傳送五次故有五次BER 02/15 13:25
maxwellyann:我了解了,感恩你唷! 給你一個推! 02/15 13:31