gr::filter::pfb_channelizer_ccf
gr::block
gnuradio/filter/pfb_channelizer_ccf.h
std::shared_ptr< pfb_channelizer_ccf > typedef std::shared_ptr<pfb_channelizer_ccf> gr::filter::pfb_channelizer_ccf::sptr sptr gr::filter::pfb_channelizer_ccf::sptr
sptr static sptr gr::filter::pfb_channelizer_ccf::make (unsigned int numchans, const std::vector< float > &taps, float oversample_rate) make gr::filter::pfb_channelizer_ccf::make unsigned int numchans const std::vector< float > & taps float oversample_rate

Build the polyphase filterbank decimator. numchans

(unsigned integer) Specifies the number of channels M

taps

(vector/list of floats) The prototype filter to populate the filterbank.

oversample_rate

(float) The oversampling rate is the ratio of the the actual output sampling rate to the normal output sampling rate. It must be rationally related to the number of channels as N/i for i in [1,N], which gives an outputsample rate of [fs/N, fs] where fs is the input sample rate and N is the number of channels.

For example, for 6 channels with fs = 6000 Hz, the normal rate is 6000/6 = 1000 Hz. Allowable oversampling rates are 6/6, 6/5, 6/4, 6/3, 6/2, and 6/1 where the output sample rate of a 6/1 oversample ratio is 6000 Hz, or 6 times the normal 1000 Hz. taps
void virtual void gr::filter::pfb_channelizer_ccf::set_taps (const std::vector< float > &taps)=0 set_taps gr::filter::pfb_channelizer_ccf::set_taps const std::vector< float > & taps

Resets the filterbank's filter taps with the new prototype filter taps

(vector/list of floats) The prototype filter to populate the filterbank.

taps
void virtual void gr::filter::pfb_channelizer_ccf::print_taps ()=0 print_taps gr::filter::pfb_channelizer_ccf::print_taps

Print all of the filterbank taps to screen.

std::vector< std::vector< float > > virtual std::vector< std::vector< float > > gr::filter::pfb_channelizer_ccf::taps () const =0 taps gr::filter::pfb_channelizer_ccf::taps

Return a vector<vector<>> of the filterbank taps

make
set_taps
void virtual void gr::filter::pfb_channelizer_ccf::set_channel_map (const std::vector< int > &map)=0 set_channel_map gr::filter::pfb_channelizer_ccf::set_channel_map const std::vector< int > & map

Set the channel map. Channels are numbers as: N/2+1 | ... | N-1 | 0 | 1 | 2 | ... | N/2 <------------------- 0 --------------------> freq

So output stream 0 comes from channel 0, etc. Setting a new channel map allows the user to specify which channel in frequency he/she wants to got to which output stream.

The map should have the same number of elements as the number of output connections from the block. The minimum value of the map is 0 (for the 0th channel) and the maximum number is N-1 where N is the number of channels.

We specify M as the number of output connections made where M <= N, so only M out of N channels are driven to an output stream. The number of items in the channel map should be at least M long. If there are more channels specified, any value in the map over M-1 will be ignored. If the size of the map is less than M the behavior is unknown (we don't wish to check every entry into the work function).

This means that if the channelizer is splitting the signal up into N channels but only M channels are specified in the map (where M <= N), then M output streams must be connected and the map and the channel numbers used must be less than N-1. Output channel number can be reused, too. By default, the map is [0...M-1] with M = N.

std::vector< int > virtual std::vector< int > gr::filter::pfb_channelizer_ccf::channel_map () const =0 channel_map gr::filter::pfb_channelizer_ccf::channel_map

Gets the current channel map.

Polyphase filterbank channelizer with gr_complex input, gr_complex output and float taps.

This block takes in complex inputs and channelizes it to M channels of equal bandwidth. Each of the resulting channels is decimated to the new rate that is the input sampling rate fs divided by the number of channels, M.

The PFB channelizer code takes the taps generated above and builds a set of filters. The set contains Mfilters and each filter contains ceil(taps.size()/decim) taps. Each tap from the filter prototype is sequentially inserted into the next filter. When all of the input taps are used, the remaining filters in the filterbank are filled out with 0's to make sure each filter has the same number of taps.

Each filter operates using the gr::blocks::fir_filter_XXX class of GNU Radio, which takes the input stream at i and performs the inner product calculation to i+(n-1) where n is the number of filter taps. To efficiently handle this in the GNU Radio structure, each filter input must come from its own input stream. So the channelizer must be provided with M streams where the input stream has been deinterleaved. This is most easily done using the gr::blocks::stream_to_streams block.

The output is then produced as a vector, where index i in the vector is the next sample from the ith channel. This is most easily handled by sending the output to a gr::blocks::vector_to_streams block to handle the conversion and passing M streams out.

The input and output formatting is done using a hier_block2 called pfb_channelizer_ccf. This can take in a single stream and outputs M streams based on the behavior described above.

The filter's taps should be based on the input sampling rate.

For example, using the GNU Radio's firdes utility to building filters, we build a low-pass filter with a sampling rate of fs, a 3-dB bandwidth of BW and a transition bandwidth of TB. We can also specify the out-of-band attenuation to use, ATT, and the filter window function (a Blackman-harris window in this case). The first input is the gain of the filter, which we specify here as unity.

self._taps = filter.firdes.low_pass_2(1, fs, BW, TB, attenuation_dB=ATT, window=fft.window.WIN_BLACKMAN_hARRIS)

The filter output can also be oversampled. The oversampling rate is the ratio of the the actual output sampling rate to the normal output sampling rate. It must be rationally related to the number of channels as N/i for i in [1,N], which gives an outputsample rate of [fs/N, fs] where fs is the input sample rate and N is the number of channels.

For example, for 6 channels with fs = 6000 Hz, the normal rate is 6000/6 = 1000 Hz. Allowable oversampling rates are 6/6, 6/5, 6/4, 6/3, 6/2, and 6/1 where the output sample rate of a 6/1 oversample ratio is 6000 Hz, or 6 times the normal 1000 Hz. A rate of 6/5 = 1.2, so the output rate would be 1200 Hz.

The theory behind this block can be found in Chapter 6 of the following book:

f. harris, "Multirate Signal Processing for Communication Systems," Upper Saddle River, NJ: Prentice Hall, Inc. 2004.

When dealing with oversampling, the above book is still a good reference along with this paper:

E. Venosa, X. Chen, and fred harris, “Polyphase analysis filter bank down-converts unequal channel bandwidths with arbitrary center frequencies - design I,” in SDR’10-WinnComm, 2010.

gr::basic_block
gr::block
gr::filter::pfb_channelizer_ccf
gr::messages::msg_accepter
gr::msg_accepter
std::enable_shared_from_this< basic_block >
gr::basic_block
d_name
d_symbol_alias
d_symbol_name
d_input_signature
d_output_signature
d_debug_logger
d_logger
msg_queue
d_rpc_vars
d_message_subscribers
gr::block
d_max_output_buffer
d_min_output_buffer
d_pmt_done
d_system_port
gr::filter::pfb_channelizer_ccf
gr::messages::msg_accepter
gr::msg_accepter
std::basic_string< Char >
std::enable_shared_from_this< basic_block >
std::map< pmt::pmt_t, msg_queue_t, msg_queue_comparator >
std::shared_ptr< io_signature >
std::shared_ptr< logger >
std::shared_ptr< pmt_base >
std::shared_ptr< rpcbasic_base >
std::string
std::vector< long >
std::vector< rpcbasic_sptr >
elements
p
- gr::filter::pfb_channelizer_ccf
  _post
- gr::filter::pfb_channelizer_ccf
  active_thread_priority
- gr::filter::pfb_channelizer_ccf
  add_item_tag
- gr::filter::pfb_channelizer_ccf
  add_item_tag
- gr::filter::pfb_channelizer_ccf
  alias
- gr::filter::pfb_channelizer_ccf
  alias_pmt
- gr::filter::pfb_channelizer_ccf
  alias_set
- gr::filter::pfb_channelizer_ccf
  alignment
- gr::filter::pfb_channelizer_ccf
  allocate_buffer
- gr::filter::pfb_channelizer_ccf
  allocate_detail
- gr::filter::pfb_channelizer_ccf
  basic_block
- gr::filter::pfb_channelizer_ccf
  basic_block
- gr::filter::pfb_channelizer_ccf
  BLACK
- gr::filter::pfb_channelizer_ccf
  blkd_input_timer_value
- gr::filter::pfb_channelizer_ccf
  block
- gr::filter::pfb_channelizer_ccf
  block
- gr::filter::pfb_channelizer_ccf
  channel_map
- gr::filter::pfb_channelizer_ccf
  check_topology
- gr::filter::pfb_channelizer_ccf
  clear_finished
- gr::filter::pfb_channelizer_ccf
  color
- gr::filter::pfb_channelizer_ccf
  consume
- gr::filter::pfb_channelizer_ccf
  consume_each
- gr::filter::pfb_channelizer_ccf
  d_blkd_input_timer_value
- gr::filter::pfb_channelizer_ccf
  d_color
- gr::filter::pfb_channelizer_ccf
  d_debug_logger
- gr::filter::pfb_channelizer_ccf
  d_input_signature
- gr::filter::pfb_channelizer_ccf
  d_logger
- gr::filter::pfb_channelizer_ccf
  d_max_output_buffer
- gr::filter::pfb_channelizer_ccf
  d_message_subscribers
- gr::filter::pfb_channelizer_ccf
  d_min_output_buffer
- gr::filter::pfb_channelizer_ccf
  d_name
- gr::filter::pfb_channelizer_ccf
  d_output_signature
- gr::filter::pfb_channelizer_ccf
  d_pmt_done
- gr::filter::pfb_channelizer_ccf
  d_rpc_set
- gr::filter::pfb_channelizer_ccf
  d_rpc_vars
- gr::filter::pfb_channelizer_ccf
  d_setlock
- gr::filter::pfb_channelizer_ccf
  d_symbol_alias
- gr::filter::pfb_channelizer_ccf
  d_symbol_name
- gr::filter::pfb_channelizer_ccf
  d_symbolic_id
- gr::filter::pfb_channelizer_ccf
  d_system_port
- gr::filter::pfb_channelizer_ccf
  d_unique_id
- gr::filter::pfb_channelizer_ccf
  declare_sample_delay
- gr::filter::pfb_channelizer_ccf
  declare_sample_delay
- gr::filter::pfb_channelizer_ccf
  delete_head_nowait
- gr::filter::pfb_channelizer_ccf
  detail
- gr::filter::pfb_channelizer_ccf
  dispatch_msg
- gr::filter::pfb_channelizer_ccf
  empty_handled_p
- gr::filter::pfb_channelizer_ccf
  empty_handled_p
- gr::filter::pfb_channelizer_ccf
  empty_p
- gr::filter::pfb_channelizer_ccf
  empty_p
- gr::filter::pfb_channelizer_ccf
  enable_update_rate
- gr::filter::pfb_channelizer_ccf
  erase_msg
- gr::filter::pfb_channelizer_ccf
  expand_minmax_buffer
- gr::filter::pfb_channelizer_ccf
  finished
- gr::filter::pfb_channelizer_ccf
  fixed_rate
- gr::filter::pfb_channelizer_ccf
  fixed_rate_ninput_to_noutput
- gr::filter::pfb_channelizer_ccf
  fixed_rate_noutput_to_ninput
- gr::filter::pfb_channelizer_ccf
  forecast
- gr::filter::pfb_channelizer_ccf
  general_work
- gr::filter::pfb_channelizer_ccf
  get_iterator
- gr::filter::pfb_channelizer_ccf
  get_msg_map
- gr::filter::pfb_channelizer_ccf
  get_tags_in_range
- gr::filter::pfb_channelizer_ccf
  get_tags_in_range
- gr::filter::pfb_channelizer_ccf
  get_tags_in_window
- gr::filter::pfb_channelizer_ccf
  get_tags_in_window
- gr::filter::pfb_channelizer_ccf
  GREY
- gr::filter::pfb_channelizer_ccf
  has_msg_handler
- gr::filter::pfb_channelizer_ccf
  has_msg_port
- gr::filter::pfb_channelizer_ccf
  history
- gr::filter::pfb_channelizer_ccf
  identifier
- gr::filter::pfb_channelizer_ccf
  input_signature
- gr::filter::pfb_channelizer_ccf
  insert_tail
- gr::filter::pfb_channelizer_ccf
  is_pc_rpc_set
- gr::filter::pfb_channelizer_ccf
  is_rpc_set
- gr::filter::pfb_channelizer_ccf
  is_set_max_noutput_items
- gr::filter::pfb_channelizer_ccf
  is_unaligned
- gr::filter::pfb_channelizer_ccf
  log_level
- gr::filter::pfb_channelizer_ccf
  make
- gr::filter::pfb_channelizer_ccf
  max_noutput_items
- gr::filter::pfb_channelizer_ccf
  max_output_buffer
- gr::filter::pfb_channelizer_ccf
  message_port_is_hier
- gr::filter::pfb_channelizer_ccf
  message_port_is_hier_in
- gr::filter::pfb_channelizer_ccf
  message_port_is_hier_out
- gr::filter::pfb_channelizer_ccf
  message_port_pub
- gr::filter::pfb_channelizer_ccf
  message_port_register_in
- gr::filter::pfb_channelizer_ccf
  message_port_register_out
- gr::filter::pfb_channelizer_ccf
  message_port_sub
- gr::filter::pfb_channelizer_ccf
  message_port_unsub
- gr::filter::pfb_channelizer_ccf
  message_ports_in
- gr::filter::pfb_channelizer_ccf
  message_ports_out
- gr::filter::pfb_channelizer_ccf
  message_subscribers
- gr::filter::pfb_channelizer_ccf
  min_noutput_items
- gr::filter::pfb_channelizer_ccf
  min_output_buffer
- gr::filter::pfb_channelizer_ccf
  mp_relative_rate
- gr::filter::pfb_channelizer_ccf
  msg_accepter
- gr::filter::pfb_channelizer_ccf
  msg_queue
- gr::filter::pfb_channelizer_ccf
  name
- gr::filter::pfb_channelizer_ccf
  nitems_read
- gr::filter::pfb_channelizer_ccf
  nitems_written
- gr::filter::pfb_channelizer_ccf
  nmsgs
- gr::filter::pfb_channelizer_ccf
  no_pc_rpc
- gr::filter::pfb_channelizer_ccf
  notify_msg_neighbors
- gr::filter::pfb_channelizer_ccf
  output_multiple
- gr::filter::pfb_channelizer_ccf
  output_multiple_set
- gr::filter::pfb_channelizer_ccf
  output_signature
- gr::filter::pfb_channelizer_ccf
  pc_input_buffers_full
- gr::filter::pfb_channelizer_ccf
  pc_input_buffers_full
- gr::filter::pfb_channelizer_ccf
  pc_input_buffers_full_avg
- gr::filter::pfb_channelizer_ccf
  pc_input_buffers_full_avg
- gr::filter::pfb_channelizer_ccf
  pc_input_buffers_full_var
- gr::filter::pfb_channelizer_ccf
  pc_input_buffers_full_var
- gr::filter::pfb_channelizer_ccf
  pc_noutput_items
- gr::filter::pfb_channelizer_ccf
  pc_noutput_items_avg
- gr::filter::pfb_channelizer_ccf
  pc_noutput_items_var
- gr::filter::pfb_channelizer_ccf
  pc_nproduced
- gr::filter::pfb_channelizer_ccf
  pc_nproduced_avg
- gr::filter::pfb_channelizer_ccf
  pc_nproduced_var
- gr::filter::pfb_channelizer_ccf
  pc_output_buffers_full
- gr::filter::pfb_channelizer_ccf
  pc_output_buffers_full
- gr::filter::pfb_channelizer_ccf
  pc_output_buffers_full_avg
- gr::filter::pfb_channelizer_ccf
  pc_output_buffers_full_avg
- gr::filter::pfb_channelizer_ccf
  pc_output_buffers_full_var
- gr::filter::pfb_channelizer_ccf
  pc_output_buffers_full_var
- gr::filter::pfb_channelizer_ccf
  pc_throughput_avg
- gr::filter::pfb_channelizer_ccf
  pc_work_time
- gr::filter::pfb_channelizer_ccf
  pc_work_time_avg
- gr::filter::pfb_channelizer_ccf
  pc_work_time_total
- gr::filter::pfb_channelizer_ccf
  pc_work_time_var
- gr::filter::pfb_channelizer_ccf
  post
- gr::filter::pfb_channelizer_ccf
  print_taps
- gr::filter::pfb_channelizer_ccf
  processor_affinity
- gr::filter::pfb_channelizer_ccf
  produce
- gr::filter::pfb_channelizer_ccf
  relative_rate
- gr::filter::pfb_channelizer_ccf
  relative_rate_d
- gr::filter::pfb_channelizer_ccf
  relative_rate_i
- gr::filter::pfb_channelizer_ccf
  remove_item_tag
- gr::filter::pfb_channelizer_ccf
  remove_item_tag
- gr::filter::pfb_channelizer_ccf
  replace_buffer
- gr::filter::pfb_channelizer_ccf
  reset_perf_counters
- gr::filter::pfb_channelizer_ccf
  rpc_set
- gr::filter::pfb_channelizer_ccf
  sample_delay
- gr::filter::pfb_channelizer_ccf
  set_alignment
- gr::filter::pfb_channelizer_ccf
  set_blkd_input_timer_value
- gr::filter::pfb_channelizer_ccf
  set_block_alias
- gr::filter::pfb_channelizer_ccf
  set_channel_map
- gr::filter::pfb_channelizer_ccf
  set_color
- gr::filter::pfb_channelizer_ccf
  set_detail
- gr::filter::pfb_channelizer_ccf
  set_fixed_rate
- gr::filter::pfb_channelizer_ccf
  set_history
- gr::filter::pfb_channelizer_ccf
  set_input_signature
- gr::filter::pfb_channelizer_ccf
  set_inverse_relative_rate
- gr::filter::pfb_channelizer_ccf
  set_is_unaligned
- gr::filter::pfb_channelizer_ccf
  set_log_level
- gr::filter::pfb_channelizer_ccf
  set_max_noutput_items
- gr::filter::pfb_channelizer_ccf
  set_max_output_buffer
- gr::filter::pfb_channelizer_ccf
  set_max_output_buffer
- gr::filter::pfb_channelizer_ccf
  set_min_noutput_items
- gr::filter::pfb_channelizer_ccf
  set_min_output_buffer
- gr::filter::pfb_channelizer_ccf
  set_min_output_buffer
- gr::filter::pfb_channelizer_ccf
  set_msg_handler
- gr::filter::pfb_channelizer_ccf
  set_output_multiple
- gr::filter::pfb_channelizer_ccf
  set_output_signature
- gr::filter::pfb_channelizer_ccf
  set_processor_affinity
- gr::filter::pfb_channelizer_ccf
  set_relative_rate
- gr::filter::pfb_channelizer_ccf
  set_relative_rate
- gr::filter::pfb_channelizer_ccf
  set_tag_propagation_policy
- gr::filter::pfb_channelizer_ccf
  set_taps
- gr::filter::pfb_channelizer_ccf
  set_thread_priority
- gr::filter::pfb_channelizer_ccf
  set_unaligned
- gr::filter::pfb_channelizer_ccf
  setup_pc_rpc
- gr::filter::pfb_channelizer_ccf
  setup_rpc
- gr::filter::pfb_channelizer_ccf
  shared_from_base
- gr::filter::pfb_channelizer_ccf
  sptr
- gr::filter::pfb_channelizer_ccf
  start
- gr::filter::pfb_channelizer_ccf
  stop
- gr::filter::pfb_channelizer_ccf
  symbol_name
- gr::filter::pfb_channelizer_ccf
  symbolic_id
- gr::filter::pfb_channelizer_ccf
  system_handler
- gr::filter::pfb_channelizer_ccf
  tag_propagation_policy
- gr::filter::pfb_channelizer_ccf
  tag_propagation_policy_t
- gr::filter::pfb_channelizer_ccf
  taps
- gr::filter::pfb_channelizer_ccf
  thread_priority
- gr::filter::pfb_channelizer_ccf
  to_basic_block
- gr::filter::pfb_channelizer_ccf
  TPP_ALL_TO_ALL
- gr::filter::pfb_channelizer_ccf
  TPP_CUSTOM
- gr::filter::pfb_channelizer_ccf
  TPP_DONT
- gr::filter::pfb_channelizer_ccf
  TPP_ONE_TO_ONE
- gr::filter::pfb_channelizer_ccf
  unaligned
- gr::filter::pfb_channelizer_ccf
  unique_id
- gr::filter::pfb_channelizer_ccf
  unset_max_noutput_items
- gr::filter::pfb_channelizer_ccf
  unset_processor_affinity
- gr::filter::pfb_channelizer_ccf
  update_rate
- gr::filter::pfb_channelizer_ccf
  vcolor
- gr::filter::pfb_channelizer_ccf
  WHITE
- gr::filter::pfb_channelizer_ccf
  WORK_CALLED_PRODUCE
- gr::filter::pfb_channelizer_ccf
  WORK_DONE
- gr::filter::pfb_channelizer_ccf
  work_return_t
- gr::filter::pfb_channelizer_ccf
  ~basic_block
- gr::filter::pfb_channelizer_ccf
  ~block
- gr::filter::pfb_channelizer_ccf
  ~msg_accepter