System object: comm.PSKDemodulator
Package: comm
Demodulate using M-ary PSK method
Y = step(H,X)
Y = step(H,X,VAR)
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 data, X,
with the PSK demodulator System object, H,
and returns Y. Input X must
be a scalar or a column vector with double or single precision data
type. If the value of the ModulationOrder property
is less than or equal to 8 and you set BitOutput to false,
or when you set the DecisionMethod property to Hard
Decision and BitOutput to true,
the object accepts an input with a signed integer data type or signed
fixed point (fi objects). Depending on the BitOutput property
value, output Y, can be integer or bit valued.
Y = step(H,X,VAR) uses soft decision demodulation
and noise variance VAR. This syntax applies when
you set the BitOutput property to true, the DecisionMethod property
to Approximate log-likelihood ratio or Log-likelihood
ratio, and the VarianceSource property
to Input port. The data type of input VAR must
be double or single precision.
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, such as dimensions,
complexity, and data type of the input data. If you change a nontunable
property or an input specification, the System object issues an
error. To change nontunable properties or inputs, you must first call
the release method to unlock the object.