Rs Decoder - Xilinx System Generator V2.1 Reference Manual

Block Parameters Dialog Box
The Xilinx puncture block can be configured using its Block Parameters dialog box.
Figure 3-38: Puncture block parameters dialog box
Parameters specific to the Xilinx Puncture block are:
Other parameters used by this block are described in the Common Parameters section
of the previous chapter.
The Puncture block does not use a Xilinx LogiCORE.

RS Decoder

n is the total number of symbols in a code block and k is the number of information or
data symbols. See the RS Encoder block documentation for more details. A Reed-
Solomon decoder can correct up to t symbols that contain errors in a codeword, where
2t = n-k.
The RS decoder can correct up to t errors or up to 2t erasures. An erasure occurs when
the position of an erred symbol is known. Erasure information is generally supplied
by the demodulator in a digital communication system, i.e. the demodulator flags
received symbols that are likely to contain errors. When a codeword is decoded, there
are three possible outcomes:
Communication
Puncture Code: specifies the puncture pattern for removing the bits from the
input.
RS (Reed-Solomon) codes are block-based error correcting codes
with a wide range of applications in digital communications and
storage. The Xilinx RS Decoder core handles both full length and
shortened systematic codes. The Reed-Solomon decoder takes a
block of digital data and processes each block and attempts to
correct errors and recover the original data.
A Reed-Solomon code is specified as RS(n,k) with s-bit symbols.
Reed-Solomon codes are usually referred to as (n,k) codes, where
1. If 2p + r < 2t (p errors, r erasures) the original transmitted code word will
always be recovered
2. The decoder will detect that it cannot recover the original code word and will
indicate a failure in decoding.
3. The decoder will mis-decode and recover an incorrect code word without any
indication.
Xilinx Blocks
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