Angle Modulation

Angle (Exponential) Modulation

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Determine the instantaneous frequency of the signal

The frequency of ф(t) is 5 Hz at t = 0 and increases linearly at a rate of 1 Hz per

second.

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Hence, in PM, the instantaneous frequency ωi varies linearly with the derivative of the modulating signal

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H. W.

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If kf is very small (that is, if |kfa(t)| << 1), then all but the first two terms are negligible

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The Maximum and Minimum carrier frequencies are ωc + kfmp and ωc - kfmp

The deviation of carrier frequency is ± kfmp.

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bandwidth is unchanged so that B = 15 KHz

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