Answer to Question #292154 in Computer Networks for koi

Question

CAT-6 twisted pair cable is a commonly used computer networks cable that provides a frequency bandwidth of up to 250 MHz. It is suitable for most varieties of Ethernet over twisted pair up to 1000 BASE-T (Gigabit Ethernet). Determine whether a signal-to-noise ratio (SNR) of 20 dB is adequate to transmit 0.9 Gbps on this cable?

Answer 1

$$SNR(dB) =10log10(SNR)$$

Therefore:

20=10log₁₀(SNR)

SNR=10² =>100

To get Capacity:

$C=Blog2(1+SNR)$

C=0.9*10⁹log₂(101)

C=5 992.39MHz

Hence the signal to noise ratio of 20dB is inadequate