Which statement is true about AM in relation to EMI?

Which statement is true about AM in relation to EMI?

• A. AM is more affected by EMI
• B. AM is less affected by EMI
• C. AM has no EMI interaction
• D. AM EMI effects are identical to FM EMI effects

Answer: (A)

EMI tends to show up as unwanted amplitude variations on the received signal. AM encodes its information in the envelope, so any extra amplitude fluctuation directly disturbs the envelope that the detector converts into audio. That makes AM highly sensitive to EMI, causing distortion and reduced intelligibility. FM, on the other hand, uses frequency deviations to carry information. Receivers typically include a limiter stage that suppresses amplitude variations before demodulation, so amplitude EMI is largely removed and has less impact on the recovered audio. Only strong, wideband interference that affects the carrier or causes wide frequency shifts would degrade FM performance. So the statement that AM is more affected by EMI is the best fit, while the others don’t reflect how AM and FM respond differently to amplitude-based interference.

EMI tends to show up as unwanted amplitude variations on the received signal. AM encodes its information in the envelope, so any extra amplitude fluctuation directly disturbs the envelope that the detector converts into audio. That makes AM highly sensitive to EMI, causing distortion and reduced intelligibility.

FM, on the other hand, uses frequency deviations to carry information. Receivers typically include a limiter stage that suppresses amplitude variations before demodulation, so amplitude EMI is largely removed and has less impact on the recovered audio. Only strong, wideband interference that affects the carrier or causes wide frequency shifts would degrade FM performance.

So the statement that AM is more affected by EMI is the best fit, while the others don’t reflect how AM and FM respond differently to amplitude-based interference.