step
System object: comm.RectangularQAMTCMDemodulator
Package: comm
Demodulate convolutionally encoded data mapped to rectangular QAM constellation
Syntax
Y = step(H,X)
Y = step(H,X,R)
Description
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.
Y = step(H,X)
demodulates the rectangular
QAM modulated input data, X
, and uses the Viterbi
algorithm to decode the resulting demodulated, convolutionally encoded
bits. X
must be a complex, double or single precision
column vector. The step method outputs a demodulated, binary data
column vector, Y
. When the convolutional encoder
represents a rate K/N code, the length of the output vector is K*L,
where L is the length of the input vector, X
.
Y = step(H,X,R)
resets the decoder to the
all-zeros state when you input a reset signal, R
that
is non-zero. R
must be a double precision or logical,
scalar integer. This syntax applies when you set the ResetInputPort
property
to true.
Note
obj
specifies the System object on which to run this step
method.
The object performs an initialization the first time the step
method is executed. This initialization locks nontunable properties and
input specifications. For more information on changing property values, see System Design in MATLAB Using System Objects.