gr::digital::packet_header_ofdm Class Reference

Header utility for OFDM signals. More...

#include <gnuradio/digital/packet_header_ofdm.h>

Inheritance diagram for gr::digital::packet_header_ofdm:

Public Types
typedef boost::shared_ptr < packet_header_ofdm >	sptr
Public Types inherited from gr::digital::packet_header_default
typedef boost::shared_ptr < packet_header_default >	sptr

Public Member Functions
	packet_header_ofdm (const std::vector< std::vector< int > > &occupied_carriers, int n_syms, const std::string &len_tag_key, const std::string &frame_len_tag_key, const std::string &num_tag_key, int bits_per_header_sym, int bits_per_payload_sym, bool scramble_header)
	~packet_header_ofdm ()
bool	header_formatter (long packet_len, unsigned char *out, const std::vector< tag_t > &tags)
	Header formatter. More...
bool	header_parser (const unsigned char *header, std::vector< tag_t > &tags)
	Inverse function to header_formatter(). More...
Public Member Functions inherited from gr::digital::packet_header_default
	packet_header_default (long header_len, const std::string &len_tag_key="packet_len", const std::string &num_tag_key="packet_num", int bits_per_byte=1)
virtual	~packet_header_default ()
sptr	base ()
sptr	formatter ()
void	set_header_num (unsigned header_num)
long	header_len ()
pmt::pmt_t	len_tag_key ()

Static Public Member Functions
static sptr	make (const std::vector< std::vector< int > > &occupied_carriers, int n_syms, const std::string &len_tag_key="packet_len", const std::string &frame_len_tag_key="frame_len", const std::string &num_tag_key="packet_num", int bits_per_header_sym=1, int bits_per_payload_sym=1, bool scramble_header=false)
Static Public Member Functions inherited from gr::digital::packet_header_default
static sptr	make (long header_len, const std::string &len_tag_key="packet_len", const std::string &num_tag_key="packet_num", int bits_per_byte=1)

Protected Attributes
pmt::pmt_t	d_frame_len_tag_key
	Tag key of the additional frame length tag. More...
const std::vector< std::vector < int > >	d_occupied_carriers
	Which carriers/symbols carry data. More...
int	d_syms_per_set
	Helper variable: Total number of elements in d_occupied_carriers. More...
int	d_bits_per_payload_sym
std::vector< unsigned char >	d_scramble_mask
	Bits are xor'd with this before tx'ing. More...
Protected Attributes inherited from gr::digital::packet_header_default
long	d_header_len
pmt::pmt_t	d_len_tag_key
pmt::pmt_t	d_num_tag_key
int	d_bits_per_byte
unsigned	d_header_number
unsigned	d_mask
boost::crc_optimal< 8, 0x07, 0xFF, 0x00, false, false >	d_crc_impl

Detailed Description

Header utility for OFDM signals.

Member Typedef Documentation

typedef boost::shared_ptr<packet_header_ofdm> gr::digital::packet_header_ofdm::sptr

Constructor & Destructor Documentation

gr::digital::packet_header_ofdm::packet_header_ofdm	(	const std::vector< std::vector< int > > &	occupied_carriers,
		int	n_syms,
		const std::string &	len_tag_key,
		const std::string &	frame_len_tag_key,
		const std::string &	num_tag_key,
		int	bits_per_header_sym,
		int	bits_per_payload_sym,
		bool	scramble_header
	)

gr::digital::packet_header_ofdm::~packet_header_ofdm

(

)

Member Function Documentation

bool gr::digital::packet_header_ofdm::header_formatter ( long  packet_len, unsigned char *  out, const std::vector< tag_t > &  tags  )

virtual

Header formatter.

Does the same as packet_header_default::header_formatter(), but optionally scrambles the bits (this is more important for OFDM to avoid PAPR spikes).

Reimplemented from gr::digital::packet_header_default.

bool gr::digital::packet_header_ofdm::header_parser ( const unsigned char *  header, std::vector< tag_t > &  tags  )

virtual

Inverse function to header_formatter().

Does the same as packet_header_default::header_parser(), but adds another tag that stores the number of OFDM symbols in the packet. Note that there is usually no linear connection between the number of OFDM symbols and the packet length because a packet might finish mid-OFDM-symbol.

Reimplemented from gr::digital::packet_header_default.

static sptr gr::digital::packet_header_ofdm::make ( const std::vector< std::vector< int > > &  occupied_carriers, int  n_syms, const std::string &  len_tag_key = "packet_len", const std::string &  frame_len_tag_key = "frame_len", const std::string &  num_tag_key = "packet_num", int  bits_per_header_sym = 1, int  bits_per_payload_sym = 1, bool  scramble_header = false  )

static

Parameters

occupied_carriers	See carrier allocator
n_syms	The number of OFDM symbols the header should be (usually 1)
len_tag_key	The tag key used for the packet length (number of bytes)
frame_len_tag_key	The tag key used for the frame length (number of OFDM symbols, this is the tag key required for the frame equalizer etc.)
num_tag_key	The tag key used for packet numbering.
bits_per_header_sym	Bits per complex symbol in the header, e.g. 1 if the header is BPSK modulated, 2 if it's QPSK modulated etc.
bits_per_payload_sym	Bits per complex symbol in the payload. This is required to figure out how many OFDM symbols are necessary to encode the given number of bytes.
scramble_header	Set this to true to scramble the bits. This is highly recommended, as it reduces PAPR spikes.

Member Data Documentation

int gr::digital::packet_header_ofdm::d_bits_per_payload_sym

protected

pmt::pmt_t gr::digital::packet_header_ofdm::d_frame_len_tag_key

protected

Tag key of the additional frame length tag.

const std::vector<std::vector<int> > gr::digital::packet_header_ofdm::d_occupied_carriers

protected

Which carriers/symbols carry data.

std::vector<unsigned char> gr::digital::packet_header_ofdm::d_scramble_mask

protected

Bits are xor'd with this before tx'ing.

int gr::digital::packet_header_ofdm::d_syms_per_set

protected

Helper variable: Total number of elements in d_occupied_carriers.

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

• packet_header_ofdm.h