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DSB AM Demodulator Passband

Demodulate DSB-AM-modulated data

Library

Analog Passband Modulation, in Modulation

Description

The DSB AM Demodulator Passband block demodulates a signal that was modulated using double-sideband amplitude modulation. The block uses the envelope detection method. The input is a passband representation of the modulated signal. Both the input and output signals are real scalar signals.

In the course of demodulating, this block uses a filter whose order, coefficients, passband ripple and stopband ripple are described by their respective lowpass filter parameters.

Typically, an appropriate Carrier frequency value is much higher than the highest frequency of the input signal. By the Nyquist sampling theorem, the reciprocal of the model's sample time (defined by the model's signal source) must exceed twice the Carrier frequency parameter.

This block works only with real inputs of type double. This block does not work inside a triggered subsystem.

Dialog Box

Input signal offset

The same as the Input signal offset parameter in the corresponding DSB AM Modulator Passband block.

Carrier frequency (Hz)

The frequency of the carrier in the corresponding DSB AM Modulator Passband block.

Initial phase (rad)

The initial phase of the carrier in radians.

Lowpass filter design method

The method used to generate the filter. Available methods are Butterworth, Chebyshev type I, Chebyshev type II, and Elliptic.

Filter order

The order of the lowpass digital filter specified in the Lowpass filter design method field .

Cutoff frequency (Hz)

The cutoff frequency of the lowpass digital filter specified in the Lowpass filter design method field in Hertz.

Passband ripple (dB)

Applies to Chebyshev type I and Elliptic filters only. This is peak-to-peak ripple in the passband in dB.

Stopband ripple (dB)

Applies to Chebyshev type II and Elliptic filters only. This is the peak-to-peak ripple in the stopband in dB.

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