Xilinx System Generator v2.1 Reference Guide
Depuncture
The Xilinx Depuncture block allows you to insert arbitrary symbol into your input data at the location specified by the depuncture code and creates a new value. This value is presented as output from the block. The Xilinx depuncture block accepts data of type UFixN_0 where N
equals the length of insert string x (the number of ones in the depuncture code) and produces output data of type UFixK_0 where K equals the length of insert string x (the length of the depuncture code ).
The Xilinx Depuncture block can be used to decode a range of punctured convolution codes. The following diagram illustrates an application of this block to implement soft decision Viterbi decoding of punctured convolution codes.
Figure 3-32: Example of Depuncture block use
The previous diagram shows a matched filter block connected to a serial to parallel block. The serial to parallel block concatenates two continuous soft inputs and presents it as a
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