question_answer 29)

    Figure 10(EP).3 shows a communication sys- tem, What is the output power when input signal is of 1-01 ? [gain m dB = 10 log10 (P0/Pt)].

Answer:

                   Here, transmission path = 5 km Loss suffered in transmission path =-2dBkm-1 x5km=-10dB Total amplifier gain = 10 dB + 20 dB = 30 dB Overall gain of signal = 30 dB -10 dB = 20 dB As, Gain in dB = 10 log 10 (P0/Pt)                                            Or