A baseband link uses an equalized telephone line to send polar NRZ current pulses at 10 ksps. The link uses ideal low pass RRC filters with α = 0.5. The output power of the digital transmitter is 0 dBm and the link has a constant attenuation of 50.0 dB. At the input to the receiver, the equivalent AWGN noise power is – 70 dBm. Assume implementation margin is 0 dB when calculating BER in parts (c) and (d).
a. What is the minimum bandwidth of the telephone line to transmit the pulses without distortion?
b. What is the signal to noise ratio at the input to the receiver in dB and as a power ratio?
c. What is the bit error rate at the receiver output and the average time between errors?
d. Rain leaks into a junction box in the link and causes the noise power at the receiver to increase to -60 dBm.
e. What is the bit error rate at the receiver output and the average time between errors in part (d)?