GNU Radio 3.6.5.1 C++ API
digital_ofdm_carrier_allocator_cvc Class Reference

Create frequency domain OFDM symbols from complex values, add pilots.This block turns a stream of complex, scalar modulation symbols into vectors which are the input for an IFFT in an OFDM transmitter. It also supports the possibility of placing pilot symbols onto the carriers. More...

#include <digital_ofdm_carrier_allocator_cvc.h>

Inheritance diagram for digital_ofdm_carrier_allocator_cvc:
gr_tagged_stream_block gr_block gr_basic_block gr_msg_accepter gruel::msg_accepter

Public Member Functions

 ~digital_ofdm_carrier_allocator_cvc ()
std::string len_tag_key ()
const int fft_len ()
std::vector< std::vector< int > > occupied_carriers ()
int work (int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
 Just like gr_block::general_work, but makes sure the input is valid.
- Public Member Functions inherited from gr_tagged_stream_block
void forecast (int noutput_items, gr_vector_int &ninput_items_required)
 Don't override this.
int general_work (int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
- Public Member Functions inherited from gr_block
virtual ~gr_block ()
unsigned history () const
void set_history (unsigned history)
bool fixed_rate () const
 Return true if this block has a fixed input to output rate.
virtual bool start ()
 Called to enable drivers, etc for i/o devices.
virtual bool stop ()
 Called to disable drivers, etc for i/o devices.
void set_output_multiple (int multiple)
 Constrain the noutput_items argument passed to forecast and general_work.
int output_multiple () const
bool output_multiple_set () const
void set_alignment (int multiple)
 Constrains buffers to work on a set item alignment (for SIMD)
int alignment () const
void set_unaligned (int na)
int unaligned () const
void set_is_unaligned (bool u)
bool is_unaligned () const
void consume (int which_input, int how_many_items)
 Tell the scheduler how_many_items of input stream which_input were consumed.
void consume_each (int how_many_items)
 Tell the scheduler how_many_items were consumed on each input stream.
void produce (int which_output, int how_many_items)
 Tell the scheduler how_many_items were produced on output stream which_output.
void set_relative_rate (double relative_rate)
 Set the approximate output rate / input rate.
double relative_rate () const
 return the approximate output rate / input rate
virtual int fixed_rate_ninput_to_noutput (int ninput)
 Given ninput samples, return number of output samples that will be produced. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this.
virtual int fixed_rate_noutput_to_ninput (int noutput)
 Given noutput samples, return number of input samples required to produce noutput. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this.
uint64_t nitems_read (unsigned int which_input)
 Return the number of items read on input stream which_input.
uint64_t nitems_written (unsigned int which_output)
 Return the number of items written on output stream which_output.
tag_propagation_policy_t tag_propagation_policy ()
 Asks for the policy used by the scheduler to moved tags downstream.
void set_tag_propagation_policy (tag_propagation_policy_t p)
 Set the policy by the scheduler to determine how tags are moved downstream.
int min_noutput_items () const
 Return the minimum number of output items this block can produce during a call to work.
void set_min_noutput_items (int m)
 Set the minimum number of output items this block can produce during a call to work.
int max_noutput_items ()
 Return the maximum number of output items this block will handle during a call to work.
void set_max_noutput_items (int m)
 Set the maximum number of output items this block will handle during a call to work.
void unset_max_noutput_items ()
 Clear the switch for using the max_noutput_items value of this block.
bool is_set_max_noutput_items ()
 Ask the block if the flag is or is not set to use the internal value of max_noutput_items during a call to work.
void expand_minmax_buffer (int port)
long max_output_buffer (size_t i)
 Returns max buffer size on output port i.
void set_max_output_buffer (long max_output_buffer)
 Sets max buffer size on all output ports.
void set_max_output_buffer (int port, long max_output_buffer)
 Sets max buffer size on output port port.
long min_output_buffer (size_t i)
 Returns min buffer size on output port i.
void set_min_output_buffer (long min_output_buffer)
 Sets min buffer size on all output ports.
void set_min_output_buffer (int port, long min_output_buffer)
 Sets min buffer size on output port port.
float pc_noutput_items ()
 Gets average noutput_items performance counter.
float pc_noutput_items_var ()
 Gets variance of noutput_items performance counter.
float pc_nproduced ()
 Gets average num items produced performance counter.
float pc_nproduced_var ()
 Gets variance of num items produced performance counter.
float pc_input_buffers_full (int which)
 Gets average fullness of which input buffer.
float pc_input_buffers_full_var (int which)
 Gets variance of fullness of which input buffer.
std::vector< float > pc_input_buffers_full ()
 Gets average fullness of all input buffers.
std::vector< float > pc_input_buffers_full_var ()
 Gets variance of fullness of all input buffers.
float pc_output_buffers_full (int which)
 Gets average fullness of which input buffer.
float pc_output_buffers_full_var (int which)
 Gets variance of fullness of which input buffer.
std::vector< float > pc_output_buffers_full ()
 Gets average fullness of all output buffers.
std::vector< float > pc_output_buffers_full_var ()
 Gets variance of fullness of all output buffers.
float pc_work_time ()
 Gets average clock cycles spent in work.
float pc_work_time_var ()
 Gets average clock cycles spent in work.
void reset_perf_counters ()
 Resets the performance counters.
void set_processor_affinity (const std::vector< int > &mask)
 Set the thread's affinity to processor core n.
void unset_processor_affinity ()
 Remove processor affinity to a specific core.
std::vector< int > processor_affinity ()
 Get the current processor affinity.
gr_block_detail_sptr detail () const
void set_detail (gr_block_detail_sptr detail)
- Public Member Functions inherited from gr_basic_block
virtual ~gr_basic_block ()
long unique_id () const
long symbolic_id () const
std::string name () const
std::string symbol_name () const
gr_io_signature_sptr input_signature () const
gr_io_signature_sptr output_signature () const
gr_basic_block_sptr to_basic_block ()
bool alias_set ()
std::string alias ()
pmt::pmt_t alias_pmt ()
void set_block_alias (std::string name)
void message_port_register_in (pmt::pmt_t port_id)
void message_port_register_out (pmt::pmt_t port_id)
void message_port_pub (pmt::pmt_t port_id, pmt::pmt_t msg)
void message_port_sub (pmt::pmt_t port_id, pmt::pmt_t target)
void message_port_unsub (pmt::pmt_t port_id, pmt::pmt_t target)
virtual bool message_port_is_hier (pmt::pmt_t port_id)
virtual bool message_port_is_hier_in (pmt::pmt_t port_id)
virtual bool message_port_is_hier_out (pmt::pmt_t port_id)
pmt::pmt_t message_ports_in ()
 Get input message port names.
pmt::pmt_t message_ports_out ()
 Get output message port names.
void _post (pmt::pmt_t which_port, pmt::pmt_t msg)
bool empty_p (pmt::pmt_t which_port)
 is the queue empty?
bool empty_p ()
size_t nmsgs (pmt::pmt_t which_port)
 How many messages in the queue?
void insert_tail (pmt::pmt_t which_port, pmt::pmt_t msg)
pmt::pmt_t delete_head_nowait (pmt::pmt_t which_port)
pmt::pmt_t delete_head_blocking (pmt::pmt_t which_port)
msg_queue_t::iterator get_iterator (pmt::pmt_t which_port)
void erase_msg (pmt::pmt_t which_port, msg_queue_t::iterator it)
virtual bool has_msg_port (pmt::pmt_t which_port)
virtual bool check_topology (int ninputs, int noutputs)
 Confirm that ninputs and noutputs is an acceptable combination.
template<typename T >
void set_msg_handler (pmt::pmt_t which_port, T msg_handler)
 Set the callback that is fired when messages are available.
- Public Member Functions inherited from gr_msg_accepter
 gr_msg_accepter ()
 ~gr_msg_accepter ()
void post (pmt::pmt_t which_port, pmt::pmt_t msg)
 send msg to msg_accepter on port which_port
- Public Member Functions inherited from gruel::msg_accepter
 msg_accepter ()
virtual ~msg_accepter ()

Protected Member Functions

int calculate_output_stream_length (const gr_vector_int &ninput_items)
 Calculate the number of output items.
- Protected Member Functions inherited from gr_tagged_stream_block
 gr_tagged_stream_block (void)
 gr_tagged_stream_block (const std::string &name, gr_io_signature_sptr input_signature, gr_io_signature_sptr output_signature, const std::string &length_tag_key)
virtual void parse_length_tags (const std::vector< std::vector< gr_tag_t > > &tags, gr_vector_int &n_input_items_reqd)
 Parse all tags on the first sample of a PDU, return the number of items per input and prune the length tags.
virtual void update_length_tags (int n_produced, int n_ports)
 Set the new length tags on the output stream.
- Protected Member Functions inherited from gr_block
 gr_block (void)
 gr_block (const std::string &name, gr_io_signature_sptr input_signature, gr_io_signature_sptr output_signature)
void set_fixed_rate (bool fixed_rate)
void add_item_tag (unsigned int which_output, uint64_t abs_offset, const pmt::pmt_t &key, const pmt::pmt_t &value, const pmt::pmt_t &srcid=pmt::PMT_F)
 Adds a new tag onto the given output buffer.
void add_item_tag (unsigned int which_output, const gr_tag_t &tag)
 Adds a new tag onto the given output buffer.
void remove_item_tag (unsigned int which_input, uint64_t abs_offset, const pmt::pmt_t &key, const pmt::pmt_t &value, const pmt::pmt_t &srcid=pmt::PMT_F)
 Removes a tag from the given input buffer.
void remove_item_tag (unsigned int which_input, const gr_tag_t &tag)
 Removes a tag from the given input buffer.
void get_tags_in_range (std::vector< gr_tag_t > &v, unsigned int which_input, uint64_t abs_start, uint64_t abs_end)
 Given a [start,end), returns a vector of all tags in the range.
void get_tags_in_range (std::vector< gr_tag_t > &v, unsigned int which_input, uint64_t abs_start, uint64_t abs_end, const pmt::pmt_t &key)
 Given a [start,end), returns a vector of all tags in the range with a given key.
- Protected Member Functions inherited from gr_basic_block
 gr_basic_block (void)
 gr_basic_block (const std::string &name, gr_io_signature_sptr input_signature, gr_io_signature_sptr output_signature)
 Protected constructor prevents instantiation by non-derived classes.
void set_input_signature (gr_io_signature_sptr iosig)
 may only be called during constructor
void set_output_signature (gr_io_signature_sptr iosig)
 may only be called during constructor
void set_color (vcolor color)
 Allow the flowgraph to set for sorting and partitioning.
vcolor color () const
bool has_msg_handler (pmt::pmt_t which_port)
 Tests if there is a handler attached to port which_port.
virtual void dispatch_msg (pmt::pmt_t which_port, pmt::pmt_t msg)

Friends

DIGITAL_API
digital_ofdm_carrier_allocator_cvc_sptr 
digital_make_ofdm_carrier_allocator_cvc (int fft_len, const std::vector< std::vector< int > > &occupied_carriers, const std::vector< std::vector< int > > &pilot_carriers, const std::vector< std::vector< gr_complex > > &pilot_symbols, const std::string &len_tag_key)

Additional Inherited Members

- Public Types inherited from gr_block
enum  { WORK_CALLED_PRODUCE = -2, WORK_DONE = -1 }
 Magic return values from general_work. More...
enum  tag_propagation_policy_t { TPP_DONT = 0, TPP_ALL_TO_ALL = 1, TPP_ONE_TO_ONE = 2 }
- Protected Types inherited from gr_basic_block
enum  vcolor { WHITE, GREY, BLACK }
- Protected Attributes inherited from gr_tagged_stream_block
std::string d_length_tag_key_str

Detailed Description

Create frequency domain OFDM symbols from complex values, add pilots.

This block turns a stream of complex, scalar modulation symbols into vectors which are the input for an IFFT in an OFDM transmitter. It also supports the possibility of placing pilot symbols onto the carriers.

The carriers can be allocated freely, if a carrier is not allocated, it is set to zero. This allows doing OFDMA-style carrier allocations.

Input: A tagged stream of complex scalars. The first item must have a tag containing the number of complex symbols in this frame. Output: A tagged stream of complex vectors of length fft_len. This can directly be connected to an FFT block. Make sure to set this block to 'reverse' for the IFFT and to deactivate FFT shifting.

Carrier indexes are always such that index 0 is the DC carrier (note: you should not allocate this carrier). The carriers below the DC carrier are either indexed with negative numbers, or with indexes larger than fft_len/2. Index -1 and index fft_len-1 both identify the carrier below the DC carrier.

Constructor & Destructor Documentation

digital_ofdm_carrier_allocator_cvc::~digital_ofdm_carrier_allocator_cvc ( )

Member Function Documentation

int digital_ofdm_carrier_allocator_cvc::calculate_output_stream_length ( const gr_vector_int ninput_items)
protectedvirtual

Calculate the number of output items.

This is basically the inverse function to forecast(): Given a number of input items, it returns the maximum number of output items.

You most likely need to override this function, unless your block is a sync block or integer interpolator/decimator.

Reimplemented from gr_tagged_stream_block.

const int digital_ofdm_carrier_allocator_cvc::fft_len ( )
inline
std::string digital_ofdm_carrier_allocator_cvc::len_tag_key ( )
inline
std::vector<std::vector<int> > digital_ofdm_carrier_allocator_cvc::occupied_carriers ( )
inline
int digital_ofdm_carrier_allocator_cvc::work ( int  noutput_items,
gr_vector_int ninput_items,
gr_vector_const_void_star input_items,
gr_vector_void_star output_items 
)
virtual

Just like gr_block::general_work, but makes sure the input is valid.

The user must override work to define the signal processing code. Check the documentation for general_work() to see what happens here.

Like gr_sync_block, this calls consume() for you (it consumes ninput_items[i] items from the i-th port).

A note on tag propagation: The PDU length tags are handled by other functions, but all other tags are handled just as in any other gr_block. So, most likely, you either set the tag propagation policy to TPP_DONT and handle the tag propagation manually, or you propagate tags through the scheduler and don't do anything here.

Parameters
noutput_itemsThe size of the writable output buffer
ninput_itemsThe exact size of the items on every input for this particular PDU. These will be consumed if a length tag key is provided!
input_itemsSee gr_block
output_itemsSee gr_block

Implements gr_tagged_stream_block.

Friends And Related Function Documentation

DIGITAL_API digital_ofdm_carrier_allocator_cvc_sptr digital_make_ofdm_carrier_allocator_cvc ( int  fft_len,
const std::vector< std::vector< int > > &  occupied_carriers,
const std::vector< std::vector< int > > &  pilot_carriers,
const std::vector< std::vector< gr_complex > > &  pilot_symbols,
const std::string &  len_tag_key 
)
friend

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