In a DSB full carrier AM transmission system, if the modulation index is doubled, then the ratio of total sideband power to carrier power increases by a factor of_____
Full Carrier DSB-SC (AM) Signal
For a full carrier AM (DSB-FC) signal:
Carrier Power:
\( P_c = \frac{A_c^2}{2R} \)
Total Sideband Power:
\( P_{SB} = \frac{m^2}{2} P_c \)
Therefore, the ratio of total sideband power to carrier power is:
\( \frac{P_{SB}}{P_c} = \frac{m^2}{2} \)
If the modulation index doubles:
\( m' = 2m \)
The new ratio becomes:
\( \frac{(2m)^2}{2} = \frac{4m^2}{2} = 4\left(\frac{m^2}{2}\right) \)
Hence, the ratio of total sideband power to carrier power increases by a factor of 4.