Consider the signal a(t) with PSD
Where  The signal is centered at the frequency 10 kHz (see Example 2.7 F in section 2.7.6) and transmitted through a channel with frequency response
with TCh = 1 ms.
At the receiver we have a first stage made by an antenna (modeled by a 100  resistance with noise temperature 200 K), followed by an amplifier with noise temperature 500 K and gain 30 dB. Assuming a narrowband channel model, determine:
a) The channel attenuation (in dB).
b) The noise PSD at the output of the amplifier.
c) The output SNR (in dB).