# Tutorial problems Analog communications

Pb1. A broadcast radio transmitter radiates 5KW power when the modulation percentage is 60% , how much is the carier power?  [Ans: 4.23 KW]

pb2. A 400 Watts carrier is modulated to a depth of 75%, calculate the total power in the modulated wave by assuming the modulating wave as sinusoidal signal. [Ans: 512.5 Watts].

Pb3. The antenna current of an AM transmitter is 8 A when only carrier is being transmitted , but is increases to 8.96 A , when the carrier is modulated by a single-tone sinusoid, find the percentage of modulation? find the antenna current when the depth of modulation changes to 0.8.  [Ans: 0.713, 9.19A].

Pb4. A 300 Watts carrier is simultaneously modulated by two audio waves with modulation percentages of 50 and 60 respectively. what will be the total side band power radiated? [Ans: 91.5 Watts].

pb5. Find the power of the signal $V(t)=&space;cos\omega&space;_{c}t&space;+&space;cos\omega&space;_{c}tcos\omega&space;_{m}t$  [Ans: 3/4 Watts].

pb6. Find the power of the signal $V(t)=&space;cos\omega&space;_{l}t&space;+&space;cos\omega&space;_{c}tcos\omega&space;_{m}t$  [Ans: 3/4 Watts].

## Author: Lakshmi Prasanna

Completed M.Tech in Digital Electronics and Communication Systems and currently working as a faculty.