Main Content

DQPSK Demodulator Baseband

Demodulate DQPSK-modulated data

Library

PM, in Digital Baseband sublibrary of Modulation

  • DQPSK Demodulator Baseband block

Description

The DQPSK Demodulator Baseband block demodulates a signal that was modulated using the differential quadrature phase shift keying method. The input is a baseband representation of the modulated signal.

The input must be a discrete-time complex signal. The output depends on the phase difference between the current symbol and the previous symbol. The first integer (or binary pair, if you set theOutput typeparameter toBit) at the block output is the initial condition of zero because there is no previous symbol.

This block accepts either a scalar or column vector input signal. For information about the data types each block port supports, seeSupported Data Types.

Outputs and Constellation Types

When you setOutput typeparameter toInteger, the block maps a phase difference of

θ + πm/2

tom, where θ represents thePhase rotationparameter andmis 0, 1, 2, or 3.

When you set theOutput typeparameter toBit, then the output contains pairs of binary values. The reference page for theDQPSK Modulator Basebandblock shows which phase differences map to each binary pair, for the cases when theConstellation orderingparameter is eitherBinaryorGray.

Dialog Box

Output type

Determines whether the output consists of integers or pairs of bits.

Constellation ordering

Determines how the block maps each integer to a pair of output bits.

Phase rotation (rad)

当前这个阶段区别和上一页ious modulated symbols results in an output of zero.

Output data type

When the parameter is set to'Inherit via internal rule'(default setting), the block will inherit the output data type from the input port. The output data type will be the same as the input data type if the input is of typesingleordouble.

For integer outputs, this block can output the data typesint8,uint8,int16,uint16,int32,uint32,single, anddouble. For bit outputs, output can beint8,uint8,int16,uint16,int32,uint32,boolean,single, ordouble.

Supported Data Types

Port Supported Data Types

Input

  • Double-precision floating point

  • Single-precision floating point

Output

  • Double-precision floating point

  • Single-precision floating point

  • Boolean whenOutput typeisBit

  • 8-, 16-, and 32-bit signed integers

  • 8-, 16-, and 32-bit unsigned integers

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced before R2006a

See Also

Blocks