1. If a signal plus noise is fed into a linear device, show that the noise figure of that device is given by F = (S/N)in/(S/N)out .
2. An antenna is pointed in a direction such that it has a noise temperature of 30 K. It is connected to a preamplifier that has a noise figure of 1.6 dB and an available gain of 30 dB over an effective bandwidth of 10 MHz.
(a) Find the effective input noise temperature for the preamplifier.
(b) Find the available noise power out of the preamplifier