comm.ConvolutionalInterleaver System object

Package: comm

Permute input symbols using shift registers with same property values


The ConvolutionalInterleaver object permutes the symbols in the input signal. Internally, this class uses a set of shift registers.

To convolutionally interleave binary data:

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

  2. Call step to convolutionally interleave according to the properties of comm.ConvolutionalInterleaver. The behavior of step is specific to each object in the toolbox.


H = comm.ConvolutionalInterleaver creates a convolutional interleaver System object™, H, that permutes the symbols in the input signal using a set of shift registers.

H = comm.ConvolutionalInterleaver(Name,Value) creates a convolutional interleaver System object, H. This object has 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 internal shift registers

Specify the number of internal shift registers as a scalar, positive integer. The default is 6.


Number of additional symbols that fit in each successive shift register

Specify the number of additional symbols that fit in each successive shift register as a positive, scalar integer. The default is 2. The first register holds zero symbols.


Initial conditions of shift registers

Specify the values that are initially stored in each shift register as a numeric scalar or vector. You do not need to specify a value for the first shift register, which has zero delay. The default is 0. The value of the first element of this property is unimportant because the first shift register has zero delay. If you set this property to a scalar, then all shift registers, except the first one, store the same specified value. If you set it to a column vector with length equal to the value of the NumRegisters property, then the i-th shift register stores the i-th element of the specified vector.


cloneCreate convolutional 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 convolutional interleaver object
stepPermute input symbols using shift registers


Interleave and deinterleave random data.

    hInt = comm.ConvolutionalInterleaver('NumRegisters', 3, ...
                    'RegisterLengthStep', 2, ...
                    'InitialConditions', [ -1 -2 -3]');
    hDeInt = comm.ConvolutionalDeinterleaver('NumRegisters', 3, ...
                    'RegisterLengthStep', 2, ...
                    'InitialConditions', [-1 -2 -3]');
    data = (0:20)';
    intrlvData = step(hInt, data);
    deintrlvData = step(hDeInt, intrlvData);
    % compare the original sequence, interleaved sequence and restored sequence.
    [data, intrlvData, deintrlvData]


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

Introduced in R2012a

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