Convolutional soft-decision sequential decoder generic (virtual) class for algorithm internal use. It is tainted by the type of code tree node+edge tag that is algorithm dependant. It contains the code tree root node and some common methods. More...

#include <CC_SequentialDecodingInternal.h>

Public Member Functions
	CC_SequentialDecodingInternal ()
virtual	~CC_SequentialDecodingInternal ()
void	reset ()
Protected Member Functions
float	log2 (float x)
void	init_root ()
virtual void	visit_node_forward (CC_TreeNodeEdge< T_IOSymbol, T_Register, T_Tag > *node, const CC_ReliabilityMatrix &relmat)=0
void	back_track (CC_TreeNodeEdge< T_IOSymbol, T_Register, T_Tag > *node_edge, std::vector< T_IOSymbol > &decoded_message, bool mark_nodes=false)
void	print_dot_internal (std::ostream &os)
Protected Attributes
CC_TreeNodeEdge< T_IOSymbol, T_Register, T_Tag > *	root_node
	Root node.

Detailed Description

template<typename T_Register, typename T_IOSymbol, typename T_Tag>
class ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >

Convolutional soft-decision sequential decoder generic (virtual) class for algorithm internal use. It is tainted by the type of code tree node+edge tag that is algorithm dependant. It contains the code tree root node and some common methods.

Template Parameters:

T_Register	Type of the encoder internal registers
T_IOSymbol	Type of the input and output symbols
T_EdgeTag	Type of the code tree node+edge tag

Constructor & Destructor Documentation

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::CC_SequentialDecodingInternal ( ) [inline]

Constructor

Parameters:

constraints Vector of register lengths (constraint length + 1). The number of elements determines k.

genpoly_representations Generator polynomial numeric representations. There are as many elements as there are input bits (k). Each element is itself a vector with one polynomial value per output bit. The smallest size of these vectors is retained as the number of output bits n. The input bits of a symbol are clocked simultaneously into the right hand side, or least significant position of the internal registers. Therefore the given polynomial representation of generators should follow the same convention.

                                        :
        root_node(0)
        {}

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

virtual ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::~CC_SequentialDecodingInternal ( ) [inline, virtual]

Destructor

        {
        if (root_node)
        {
            delete root_node;
            root_node = 0;
        }
        }

Member Function Documentation

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

void ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::back_track	(	CC_TreeNodeEdge< T_IOSymbol, T_Register, T_Tag > *	node_edge,
		std::vector< T_IOSymbol > &	decoded_message,
		bool	mark_nodes = `false`
	)		`[inline, protected]`

Back track from a node. When the node is the selected terminal node it is used to retrieve the decoded message

Parameters:

node	Node to track back from
decoded_message	Symbols corresponding to the edge ordered from root node to the given node
mark_nodes	Mark the nodes along the path

    {
        std::vector<T_IOSymbol> reversed_message;
        CC_TreeNodeEdge<T_IOSymbol, T_Register, T_Tag> *cur_node_edge = node_edge;
        CC_TreeNodeEdge<T_IOSymbol, T_Register, T_Tag> *incoming_node_edge;

        reversed_message.push_back(cur_node_edge->get_in_symbol());

        while (incoming_node_edge = (cur_node_edge->get_incoming_node_edge()))
        {
            cur_node_edge->set_on_final_path(mark_nodes);

            if (incoming_node_edge->get_depth() >= 0) // don't take root node
            {
                reversed_message.push_back(incoming_node_edge->get_in_symbol());
            }

            cur_node_edge = incoming_node_edge;
        }

        decoded_message.resize(reversed_message.size());
        std::reverse_copy(reversed_message.begin(), reversed_message.end(), decoded_message.begin());
    }

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

void ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::init_root ( ) [inline, protected]

Initialize process at the root node

    {
        root_node = new CC_TreeNodeEdge<T_IOSymbol, T_Register, T_Tag>(0, 0, 0, 0.0, 0.0, -1);
    }

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

float ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::log2 ( float x ) [inline, protected]

Base 2 logarithm

    {
        return log(x)/log(2.0);
    }

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

void ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::print_dot_internal ( std::ostream & os ) [inline, protected]

Print the code tree in Graphviz dot format

Parameters:

os	Output stream

    {
        CC_TreeGraphviz<T_IOSymbol, T_Register, T_Tag>::create_dot(root_node, os);
    }

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

void ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::reset ( ) [inline]

Reset the decoding process

Reimplemented in ccsoft::CC_FanoDecoding< T_Register, T_IOSymbol >, and ccsoft::CC_StackDecoding< T_Register, T_IOSymbol >.

    {
        if (root_node)
        {
            delete root_node;
            root_node = 0;
        }
    }

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

virtual void ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::visit_node_forward	(	CC_TreeNodeEdge< T_IOSymbol, T_Register, T_Tag > *	node,
		const CC_ReliabilityMatrix &	relmat
	)		`[protected, pure virtual]`

Visit a new node in the code tree

Parameters:

node	Node to visit
relmat	Reliability matrix reference

Implemented in ccsoft::CC_FanoDecoding< T_Register, T_IOSymbol >, and ccsoft::CC_StackDecoding< T_Register, T_IOSymbol >.

Member Data Documentation

template<typename T_Register, typename T_IOSymbol, typename T_Tag>

CC_TreeNodeEdge<T_IOSymbol, T_Register, T_Tag>* ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >::root_node [protected]

Root node.

The documentation for this class was generated from the following file:

/shared/development/google_code/rssoft/libccsoft/lib/CC_SequentialDecodingInternal.h

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

template<typename T_Register, typename T_IOSymbol, typename T_Tag> class ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

template<typename T_Register, typename T_IOSymbol, typename T_Tag>
class ccsoft::CC_SequentialDecodingInternal< T_Register, T_IOSymbol, T_Tag >