DQPSK Demodulator Baseband
Demodulates data modulated using the DQPSK method.
Description
Block DQPSK Demodulator Baseband demodulates a signal that has been modulated using differential quadrature phase shift keying (DQPSK). A basic representation of the modulated signal is input.
The input signal must be a discrete complex signal. The output depends on the phase difference between the current and previous symbol. The first integer (or binary pair if the Output type parameters are set to Bit) at the block output is an initial state of zero, since there is no previous symbol.
Output data types and constellations
If the Output type parameter is set to Integer, the block displays the phase difference and , where is the value of the Phase rotation parameter and takes the value 0, 1, 2 or 3.
If the Output type parameters are set to Bit, the output is pairs of binary values.
The reference page for the DQPSK Modulator Baseband block shows which phase differences correspond to each binary pair, for cases where the Constellation ordering parameters are set to Binary or Gray.
Ports
Parameters
Output type - output signal type
Integer (by default) | Bit
Indicates whether the output signal consists of integers or bit pairs.
Constellation ordering - constellation ordering
Gray (By default) | Binary
Determines how the block maps each pair of input bits to the corresponding integer, using either the Binary or Gray scheme.
*Phase rotation (rad)` -phase rotation
pi/4 (By default).
The phase difference between the previous and current modulated symbols when the input is zero.