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Integer-Output RS Decoder HDL Optimized

Decode data using Reed-Solomon (RS) decoder

  • Integer-Output RS Decoder HDL Optimized block

Libraries:
Communications Toolbox HDL Support / Error Detection and Correction / Block

Description

The Integer-Output RS Decoder HDL Optimized block decodes data using RS decoder. The RS decoding follows the same standards as any other cyclic redundancy code. Use this block to model communications system forward error correction (FEC) codes. The block provides an architecture suitable for HDL code generation and hardware deployment.

For more information about the RS decoder, see the Integer-Output RS Decoder block. For more information on representing data for RS codes, see Integer Format (Reed-Solomon Only).

Ports

Input

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Input data, specified as a scalar representing one symbol. For binary point scaling, the input data type must be an integer or fixdt. The double data type is allowed for simulation, but not for HDL code generation.

Data Types: double | int8 | int16 | int32 | int64 | fixed point

Start of input frame indicator, specified as a Boolean scalar.

Data Types: Boolean

End of input frame indicator, specified as a Boolean scalar.

Data Types: Boolean

Valid input data indicator, specified as a Boolean scalar.

This is a control signal that indicates if the data on the dataIn port is valid.

Data Types: Boolean

Output

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Decoded message data, returned as a scalar. This output data width is the same as the input data width.

Data Types: double | int8 | int16 | int32 | int64 | fixed point

Start of output frame indicator, returned as a Boolean scalar.

Data Types: Boolean

End of output frame indicator, returned as a Boolean scalar.

Data Types: Boolean

Valid output data indicator, returned as a Boolean scalar.

This is a control signal that indicates if the data on the dataOut port is valid.

Data Types: Boolean

Indications of corruption of the received data, returned as a Boolean scalar.

When this value is 1 (true) , the output contains at least one error. When this value is 0 (false), the output contains zero errors.

If the number of errors in the input codeword is greater than (Codeword lengthMessage length)/2, the block outputs data without correcting the errors and sets the errOut port to 1 (true) to indicate that errors that cannot be corrected exist in the input codeword.

Data Types: Boolean

Number of corrected errors, returned as a nonnegative scalar.

The maximum number of errors an RS code can correct is equal to (Codeword lengthMessage length)/2. If the number of errors in the input codeword is greater than (Codeword lengthMessage length)/2, the block outputs data without correcting the errors and sets the numErrors port to 0 to indicate that none of those errors can be corrected.

Dependencies

To enable this port, select the Output number of corrected symbol errors parameter.

Data Types: uint8

Parameters

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Specify the codeword length.

The codeword length N must be an integer equal to 2M – 1, where M is an integer in the range from 3 to 16. For more information on representing data for RS codes, see Integer Format (Reed-Solomon Only).

Specify the message length.

For more information on representing data for RS codes, see Integer Format (Reed-Solomon Only).

Specify the source of the primitive polynomial.

  • Select Auto to specify the primitive polynomial based on the Codeword length parameter value. The degree of the primitive polynomial is calculated as M = ceil(log2(Codeword length).

  • Select Property to specify the primitive polynomial using the Primitive polynomial parameter.

Specify a binary row vector representing the primitive polynomial in descending order of powers.

For more information on how to specify a primitive polynomial, see Primitive Polynomials and Element Representations.

Dependencies

To enable this parameter, set the Source of primitive polynomial parameter to Property.

Specify the source of the starting power for roots of the primitive polynomial.

  • Select Property to enable the B value parameter.

  • Select Auto, to use the B value parameter default value of 1.

The starting exponent of the roots.

Dependencies

To enable this parameter, set the Source of B, the starting power for roots of the primitive polynomial parameter to Property.

Select this parameter to enable the numErrors output port. This port outputs the number of corrected errors.

Algorithms

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This figure shows a sample output of the Integer-Output RS Decoder HDL Optimized block with a default configuration.

Extended Capabilities

Version History

Introduced in R2012b

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