What is the deviation ratio for an FM signal with a maximum deviation of ±7.5 kHz and a maximum modulation rate of 3.5 kHz?

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Multiple Choice

What is the deviation ratio for an FM signal with a maximum deviation of ±7.5 kHz and a maximum modulation rate of 3.5 kHz?

Deviation ratio shows how wide the FM frequency swing is compared to the highest modulating frequency. It’s found by dividing the peak frequency deviation by the maximum modulating frequency. Here, 7.5 kHz divided by 3.5 kHz equals about 2.14, so the deviation ratio is 2.14 (unitless). This means the peak deviation is roughly twice the highest modulation frequency, which also relates to how the signal’s bandwidth scales with modulation. The other numeric options would come from using a different divisor or misplacing the decimal, but the standard calculation uses 7.5 kHz over 3.5 kHz.

Deviation ratio shows how wide the FM frequency swing is compared to the highest modulating frequency. It’s found by dividing the peak frequency deviation by the maximum modulating frequency. Here, 7.5 kHz divided by 3.5 kHz equals about 2.14, so the deviation ratio is 2.14 (unitless). This means the peak deviation is roughly twice the highest modulation frequency, which also relates to how the signal’s bandwidth scales with modulation. The other numeric options would come from using a different divisor or misplacing the decimal, but the standard calculation uses 7.5 kHz over 3.5 kHz.

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