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Deinterleave symbols using set of shift registers with GPU

To use this object, you must install Parallel Computing Toolbox™ and have access to a supported GPU. If the host computer has a GPU configured, processing uses the GPU. Otherwise, processing uses the CPU. For more information about GPUs, see GPU Computing (Parallel Computing Toolbox).


The comm.gpu.ConvolutionalDeinterleaver System object™ deinterleaves the symbols in the input sequence with a graphics processing unit (GPU).

To deinterleave the symbols in the input sequence with GPU:

  1. Create the comm.gpu.ConvolutionalDeinterleaver object and set its properties.

  2. Call the object with arguments, as if it were a function.

To learn more about how System objects work, see What Are System Objects?



deintrlvr = comm.gpu.ConvolutionalDeinterleaver creates a default convolutional deinterleaver System object.


deintrlvr = comm.gpu.ConvolutionalDeinterleaver(Name=Value) sets Properties using one or more name-value arguments. For example, NumRegisters=10 specifies the number of internal shift registers.

intrlvr = comm.gpu.ConvolutionalDeinterleaver(m,b,ic) sets the NumRegisters property to m, the RegisterLengthStep property to b, and the InitialConditions property to ic.


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Unless otherwise indicated, properties are nontunable, which means you cannot change their values after calling the object. Objects lock when you call them, and the release function unlocks them.

If a property is tunable, you can change its value at any time.

For more information on changing property values, see System Design in MATLAB Using System Objects.

Number of internal shift registers, specified as a positive integer.

Data Types: double

Number of additional symbols that fit in each successive shift register, specified as a positive integer. The first register holds zero symbols.

Data Types: double

Initial conditions of the shift registers, specified as one of these values.

  • Scalar — All shift registers, except the last one, store the same specified value.

  • Column vector — If the length of the column vector equals the value of the NumRegisters property, then the kth shift register stores the (N–k+1)th element of the specified vector. N is the total number of shift registers.

You do not need to specify a value for the first shift register, which has zero delay. Because the first shift register has zero delay, the object ignores the first element of this property.

Data Types: double



deintrlvseq = deintrlvr(intrlvseq) deinterleaves the input sequence of symbols inputseq by using a set of shift registers. The output is the deinterleaved sequence.

For information about delays, see Delays of Convolutional Interleaving and Deinterleaving.

Input Arguments

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Interleaved sequence of symbols, specified as a column vector. This sequence must be one that was interleaved using the comm.gpu.ConvolutionalInterleaver System object or comm.ConvolutionalInterleaver System object.

To decrease data transfer latency, format the input signal as a gpuArray (Parallel Computing Toolbox) object. For more information, see Array Processing with GPU-based System Objects.

Data Types: double | single | uint32 | int32

Output Arguments

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Deinterleaved sequence of symbols, returned as a column vector with the same data type and size as the intrlvseq input.

Object Functions

To use an object function, specify the System object as the first input argument. For example, to release system resources of a System object named obj, use this syntax:


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stepRun System object algorithm
releaseRelease resources and allow changes to System object property values and input characteristics
resetReset internal states of System object


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Create GPU-based convolutional interleaver and deinterleaver System objects.

intrlvr = comm.gpu.ConvolutionalInterleaver('NumRegisters',2, ...
deintrlvr = comm.gpu.ConvolutionalDeinterleaver('NumRegisters',2, ...

Generate a random data sequence. Pass the data sequence through the interleaver and then the deinterleaver.

data = (0:20)';
intrlvData = intrlvr(data);
deintrlvData = deintrlvr(intrlvData);

Display the original sequence, interleaved sequence, and restored sequence.

[data intrlvData deintrlvData]
ans = 21×3

     0     0     0
     1     0     0
     2     2     0
     3     0     0
     4     4     0
     5     0     0
     6     6     0
     7     1     1
     8     8     2
     9     3     3

The delay through the interleaver and deinterleaver pair is equal to the product of the NumRegisters and RegisterLengthStep properties.

intrlvDelay = intrlvr.NumRegisters * intrlvr.RegisterLengthStep
intrlvDelay = 6

After accounting for this delay, verify that the original and deinterleaved data are identical.

numSymErrors = symerr(data(1:end-intrlvDelay), ...
numSymErrors = 0

More About

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Extended Capabilities

Version History

Introduced in R2012a