alleryStart learning →In AM (amplitude modulation), modulating signal varies:
AAmplitude (envelope) of carrier; carrier frequency fixed
BFrequency
CPhase
DRandom
Answer & Solution
Correct answer: A. Amplitude (envelope) of carrier; carrier frequency fixed
**AM:** amplitude varies with information signal.
**Mathematically:** s_AM(t) = (A + m(t)) cos(ω_c t).
Modulation index μ = m_max/A. Over-modulation (μ > 1)
→ envelope distortion.
**Bandwidth:** 2 × m_max frequency.
Keep practising GATE ECE — Core
Browse all GATE ECE — Core questions for GATE ECE, or explore more Electronics & Communication topics.
Related questions
For n-bit ADC with full-scale V_FS, resolution (LSB) is:Cutoff frequency of RC low-pass filter:Wave equation in vacuum (Maxwell):VSWR (Voltage Standing Wave Ratio) for matched load (R_L = Z_0):Characteristic impedance of a lossless transmission line:Shannon channel capacity:FM (frequency modulation) varies:Transfer function 1/(s² + 2s + 5) has poles at: