Question

On radiating (sending out) an AM modulated signal, the total radiated power is due to energy carried by ${\omega }_c,{\omega }_c-{\omega }_m$ & ${\omega }_c+{\omega }_m$. Suggest ways to minimize cost of radiation without compromising on information.

Answer 1

Only side band $({\omega }_c-{\omega }_m)$, and ${\omega }_c+{\omega }_m$ are the frequencies to carry information in amplitude modulated signal. SO to minimize the cost of radiating the information signals we can send either ${\omega }_c+{\omega }_m$ or ${\omega }_c-{\omega }_m$ or both ${\omega }_c+{\omega }_m$ and ${\omega }_c-{\omega }_m$.