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Punctures a data stream and returns it at a higher rate.

Puncturing is the process of artificially increasing the rate of the input data by selectively deleting certain elements in the input data stream. The positions where the elements are deleted from the input data stream are defined by the puncture pattern matrix. Elements in the input data stream that correspond to values of zero in the puncture pattern matrix are omitted from the data stream output. The rate of the output data stream is given by the following equation:

R o u t = R i n × p q ( p q L )
where the input data stream arrives at a rate R in and the puncture pattern is a P× Q matrix containing L zeros.
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input data stream

The data stream with a rate to be increased by puncturing. This data stream is usually obtained from the output of a block or convolutional encoder.

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puncture pattern

A binary-valued matrix that determines which elements in the input data stream are omitted.

Note  

The puncture pattern matrix is chronologically ordered by columns with respect to the input data stream. If the dimensions of the puncture pattern matrix are m×n, the m elements of the first column correspond to the first m elements of the input data stream, and so on.

Default: 1

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error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: no error

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reset?

A Boolean that determines whether this node uses the stored state information from a previous iteration while puncturing the input data stream in the current iteration.

Note  

When the length L of the input data stream is not an integer multiple of the product P×Q of the P×Q puncture pattern matrix, the last L modulo (P×Q) bits are buffered inside the node.

TRUE Clears all previous state information and reinitializes the buffers.
FALSE Uses the stored state information from the previous iteration while puncturing the input data stream in the current iteration. The buffered elements are added to the beginning of the input data stream during the next iteration, prior to the puncturing operation.

Default: TRUE

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output data stream

The data stream returned by this node, which consists of all elements in the input data stream except those that were deleted during the puncturing operation.

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error out

Error information. The node produces this output according to standard error behavior.