What is the approximate ratio of peak envelope power to average power during normal voice modulation peak in a single-sideband phone signal?

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Multiple Choice

What is the approximate ratio of peak envelope power to average power during normal voice modulation peak in a single-sideband phone signal?

In SSB, the important idea is crest factor—the relationship between how peaky the modulation is and how much power you actually average over time. The peak envelope power is the highest instantaneous RF power produced when the speech waveform reaches its maximum, while the average power is the long-term mean of that power. For normal voice modulation, the speech envelope isn’t constant; it has peaks but spends a good amount of time well below those peaks. This gives a crest factor of about 2.5 to 1, meaning the peak power is roughly 2.5 times the average power. In practical terms, the radio punch you see at a vocal peak is about 4 dB higher than the average power, so the approximate ratio is 2.5 to 1.

In SSB, the important idea is crest factor—the relationship between how peaky the modulation is and how much power you actually average over time. The peak envelope power is the highest instantaneous RF power produced when the speech waveform reaches its maximum, while the average power is the long-term mean of that power.

For normal voice modulation, the speech envelope isn’t constant; it has peaks but spends a good amount of time well below those peaks. This gives a crest factor of about 2.5 to 1, meaning the peak power is roughly 2.5 times the average power. In practical terms, the radio punch you see at a vocal peak is about 4 dB higher than the average power, so the approximate ratio is 2.5 to 1.

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