Demodulate convolutionally encoded data mapped to M-ary PSK signal constellation
The PSKTCMDemodulator
object uses the Viterbi
algorithm to decode a trellis-coded modulation (TCM) signal that was
previously modulated using a PSK signal constellation.
To demodulate a signal that was modulated using trellis-coded modulation:
Define and set up your PSK TCM demodulator object. See Construction.
Call step
to demodulate the signal
according to the properties of comm.PSKTCMDemodulator
.
The behavior of step
is specific to each object in
the toolbox.
Note
Starting in R2016b, instead of using the step
method
to perform the operation defined by the System object™, you can
call the object with arguments, as if it were a function. For example, y
= step(obj,x)
and y = obj(x)
perform
equivalent operations.
H = comm.PSKTCMDemodulator
creates a trellis-coded,
M-ary phase shift, keying (PSK TCM) demodulator System object, H
.
This object demodulates convolutionally encoded data that has been
mapped to an M-PSK constellation.
H = comm.PSKTCMDemodulator(
creates
a PSK TCM demodulator object, Name
,Value
)H
, with each specified
property set to the specified value. You can specify additional name-value
pair arguments in any order as (Name1
,Value1
,...,NameN
,ValueN
).
H = comm.PSKTCMDemodulator(TRELLIS,
creates
a PSK TCM demodulator System object, Name
,Value
)H
. This
object has the TrellisStructure
property set to TRELLIS
and
the other specified properties set to the specified values.
|
Trellis structure of convolutional code Specify trellis as a MATLAB structure that contains the trellis
description of the convolutional code. Use the |
|
Termination method of encoded frame Specify the termination method as one of When you set this property to When you set this property to When you set property to |
|
Traceback depth for Viterbi decoder Specify the scalar, integer number of trellis branches to construct
each traceback path. The default is When you set the When you set the |
|
Enable demodulator reset input Set this property to |
|
Number of points in signal constellation Specify the number of points in the signal constellation used to map the convolutionally
encoded data as a positive, integer scalar value. The number of points must be
|
|
Data type of output Specify output data type as |
reset | Reset states of the PSK TCM demodulator object |
step | Demodulate convolutionally encoded data mapped to M-ary PSK constellation |
Common to All System Objects | |
---|---|
release | Allow System object property value changes |
This object implements the algorithm, inputs, and outputs described on the M-PSK TCM Decoder block reference page. The object properties correspond to the block parameters.
comm.GeneralQAMTCMDemodulator
| comm.PSKTCMModulator
| comm.RectangularQAMTCMDemodulator
| comm.ViterbiDecoder