Communications Blockset

General QAM Demodulator Baseband

Demodulate QAM-modulated data

Library

AM, in Digital Baseband sublibrary of Modulation

Description

The General QAM Demodulator Baseband block demodulates a signal that was modulated using quadrature amplitude modulation. The input is a baseband representation of the modulated signal.

The input must be a discrete-time complex signal. The Signal constellation parameter defines the constellation by listing its points in a vector of complex numbers. The block maps the mth point in the Signal constellation vector to the integer m-1.

The input can be either a scalar or a frame-based column vector.

Processing an Upsampled Modulated Signal

The input signal can be an upsampled version of the modulated signal. The Samples per symbol parameter is the upsampling factor. It must be a positive integer. For more information, see Upsampled Signals and Rate Changes in Using the Communications Blockset.

Dialog Box

Signal constellation

A real or complex vector that lists the constellation points.

Samples per symbol

The number of input samples that represent each modulated symbol.

Pair Block

General QAM Modulator Baseband

See Also

Rectangular QAM Demodulator Baseband

General Multiplexed Interleaver

General QAM Demodulator Passband