comm.HelicalInterleaver System object

Package: comm

Permute input symbols using helical array


The HelicalInterleaver object permutes the symbols in the input signal by placing them in an array in a helical arrangement and then sending rows of the array to the output port.

To helically interleave input symbols:

  1. Define and set up your helical interleaver object. See Construction.

  2. Call step to interleave input symbols according to the properties of comm.HelicalInterleaver. The behavior of step is specific to each object in the toolbox.


H = comm.HelicalInterleaver creates a helical interleaver System object™, H. This object permutes the input symbols in the input signal by placing them in an array in a helical arrangement.

H = comm.HelicalInterleaver(Name,Value) creates a helical interleaver object, 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).



Number of columns in helical array

Specify the number of columns in the helical array as a positive integer scalar value. The default is 6.


Size of each group of input symbols

Specify the size of each group of input symbols as a positive integer scalar value. The default is 4.


Helical array step size

Specify the number of rows of separation between consecutive input groups in their respective columns of the helical array. This property requires as a positive integer scalar value . The default is 1.


Initial conditions of helical array

Specify the value that is initially stored in the helical array as a numeric scalar value. The default is 0.


cloneCreate helical interleaver object with same property values
getNumInputsNumber of expected inputs to step method
getNumOutputsNumber of outputs from step method
isLockedLocked status for input attributes and nontunable properties
releaseAllow property value and input characteristics changes
resetReset states of the helical interleaver object
stepPermute input symbols using a helical array


Interleave and deinterleave random data.

    hInt = comm.HelicalInterleaver('GroupSize', 2, ...
                    'NumColumns', 3, ...
                    'InitialConditions', -1);
    hDeInt = comm.HelicalDeinterleaver('GroupSize', 2, ...
                    'NumColumns', 3, ...
                    'InitialConditions', -1);
    data = randi(7, 6, 1);
    intData = step(hInt, data);
    deIntData = step(hDeInt, intData);

    % compare the original sequence, interleaved sequence, and restored sequence
    [data, intData, deIntData]


This object implements the algorithm, inputs, and outputs described on the Helical Interleaver block reference page. The object properties correspond to the block parameters.

Introduced in R2012a

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