Polyphase_filter_vhdl/poly_fir_pkg.vhd

LIBRARY ieee;
USE ieee.std_logic_1164.ALL;
USE ieee.numeric_std.ALL;
USE ieee.std_logic_unsigned.ALL;
USE ieee.std_logic_signed.ALL;

PACKAGE POLY_FIR_PKG IS

  -- NOTES and PACKAGE INSTRUCTIONS :
  -- cst_downsampling_factor must be a multiplier OF cst_nb_samples_adc_in
  -- and cst_nb_subfilters/cst_nb_samples_adc_in*cst_downsampling_factor must be an integer
  -- with cst_downsampling_factor < or = cst_nb_subfilters.
  --
  -- INPUT  : vector of samples (cst_nb_samples_adc_in samples);
  -- OUTPUT : 2D matrix of samples (matrix_fir_data_out(y)(x), with y the
  -- subfilter number, and x the xth parallel fir);
  --
  -- the lower parallel fir, the older result.



  FUNCTION log2_sup_integer (number : natural) RETURN natural;
  FUNCTION log2_inf_integer (number : natural) RETURN natural;

  -- -- CONSTANTS -- --

  -- ADC
  CONSTANT cst_w_in  : natural := 6;    -- ADC in bitwidth

  CONSTANT cst_nb_samples_adc_in : natural := 80;  -- ADC in nb samples

  -- FILTER
  --coefficients
  CONSTANT cst_w_coeff                         : natural := 8;  -- coeffs bitwidth
  CONSTANT cst_nb_coeffs_filter_in             : natural := 7*20;
  CONSTANT cst_log2_sup_nb_coeffs_subfilter_in : natural := 3;

  -- FIR
  CONSTANT cst_downsampling_factor : natural := 8;
  -- POLYPHASE FILTER
  CONSTANT cst_nb_subfilters       : natural := 20;
  

  -- -- CALCULATIONS -- --

  CONSTANT cst_w_out : natural := cst_w_in + cst_w_coeff+cst_log2_sup_nb_coeffs_subfilter_in;

  -- SHIFT REG

  CONSTANT cst_nb_coeffs_subfilter_in      : natural := cst_nb_coeffs_filter_in/cst_nb_subfilters;
  CONSTANT cst_nb_samples_shiftreg_temp_in : natural := cst_nb_coeffs_subfilter_in + cst_nb_samples_adc_in/cst_downsampling_factor;
  -- mult
  CONSTANT cst_w_mult_out                  : natural := cst_w_coeff+cst_w_in;
  -- adder
  CONSTANT cst_log2_adder_stages           : natural := cst_log2_sup_nb_coeffs_subfilter_in;
  -- fir
  CONSTANT cst_w_fir_adder_out             : natural := cst_w_mult_out+cst_log2_adder_stages;
  CONSTANT cst_nb_parallel_firs            : natural := cst_nb_samples_adc_in/cst_downsampling_factor;

  -- TYPES

  -- ADC
  SUBTYPE smpl_adc_data_in IS std_logic_vector(cst_w_in-1 DOWNTO 0);
  SUBTYPE smpl_fir_data_out IS std_logic_vector(cst_w_out-1 DOWNTO 0);


  -- SHIFT REG

  TYPE vect_adc_data_out IS ARRAY (0 TO cst_nb_samples_adc_in-1) OF smpl_adc_data_in;
  TYPE vect_fir_data_in IS ARRAY(0 TO cst_nb_coeffs_subfilter_in-1) OF smpl_adc_data_in;
  TYPE vect_reg_data IS ARRAY(0 TO cst_nb_samples_shiftreg_temp_in-1) OF smpl_adc_data_in;
  TYPE matrix_reg_data IS ARRAY(0 TO cst_nb_subfilters-1) OF vect_reg_data;

  TYPE matrix_reg_data_out IS ARRAY(0 TO cst_nb_parallel_firs-1) OF vect_fir_data_in;
  TYPE matrix3D_reg_data_out IS ARRAY (0 TO cst_nb_subfilters-1) OF matrix_reg_data_out;

  -- FILTER

  SUBTYPE smpl_coeff IS std_logic_vector(cst_w_coeff-1 DOWNTO 0);

  -- mult
  SUBTYPE smpl_mult_data_out IS std_logic_vector(cst_w_mult_out-1 DOWNTO 0);
  SUBTYPE smpl_mult_data_out_signed IS signed(cst_w_mult_out-1 DOWNTO 0);
  SUBTYPE smpl_coeffs_signed IS signed(cst_w_coeff-1 DOWNTO 0);
  SUBTYPE smpl_mult_data_in_signed IS signed(cst_w_in-1 DOWNTO 0);
  TYPE vect_polyfir_coeffs_in IS ARRAY (0 TO cst_nb_coeffs_filter_in-1) OF smpl_coeff;
  TYPE vect_data_mult_in_signed IS ARRAY(0 TO cst_nb_coeffs_subfilter_in-1) OF smpl_mult_data_in_signed;
  TYPE vect_fir_coeffs_in IS ARRAY(0 TO cst_nb_coeffs_subfilter_in-1) OF smpl_coeff;
  TYPE vect_mult_coeffs_signed IS ARRAY(0 TO cst_nb_coeffs_subfilter_in-1) OF smpl_coeffs_signed;
  TYPE vect_mult_data_out IS ARRAY(0 TO cst_nb_coeffs_subfilter_in-1) OF smpl_mult_data_out;
  TYPE vect_mult_data_out_signed IS ARRAY(0 TO cst_nb_coeffs_subfilter_in-1) OF smpl_mult_data_out_signed;
  TYPE matrix_fir_coeffs_in IS ARRAY (0 TO cst_nb_subfilters-1) OF vect_fir_coeffs_in;

  -- adder
  SUBTYPE smpl_adder_generic IS std_logic_vector(cst_w_fir_adder_out-1 DOWNTO 0);
  SUBTYPE smpl_adder_generic_signed IS signed(cst_w_fir_adder_out-1 DOWNTO 0);
  TYPE vect_adder_generic IS ARRAY(0 TO 2**(cst_log2_adder_stages)-1) OF smpl_adder_generic;
  TYPE vect_adder_generic_signed IS ARRAY(0 TO 2**(cst_log2_adder_stages)-1) OF smpl_adder_generic_signed;
  TYPE matrix_adder_generic IS ARRAY(0 TO cst_log2_adder_stages) OF vect_adder_generic;
  TYPE matrix_adder_generic_signed IS ARRAY(0 TO cst_log2_adder_stages) OF vect_adder_generic_signed;

  -- fir
  SUBTYPE smpl_fir_adder_data_out IS std_logic_vector(cst_w_fir_adder_out-1 DOWNTO 0);
  TYPE vect_fir_adder_data_out IS ARRAY (0 TO cst_nb_parallel_firs-1) OF smpl_fir_adder_data_out;
  TYPE vect_fir_data_out IS ARRAY(0 TO cst_nb_parallel_firs-1) OF smpl_fir_data_out;

  -- POLYPHASE FILTER

  TYPE matrix_fir_data_out IS ARRAY (0 TO cst_nb_subfilters-1) OF vect_fir_data_out;
  -- TYPE matrix_coeffs_polyphase_filter                IS array(0 to cst_nb_subfilters) OF vect_mult_coeffs;





END;

PACKAGE BODY POLY_FIR_PKG IS


  --functions
  FUNCTION log2_sup_integer (number : natural) RETURN natural IS
    VARIABLE result : natural;
  BEGIN

    IF(number <= 1) THEN
      result := 0;
    ELSIF(number = 2) THEN
      result := 1;
    ELSIF(number > 2 AND number <= 4) THEN
      result := 2;
    ELSIF(number > 4 AND number <= 8) THEN
      result := 3;
    ELSIF(number > 8 AND number <= 16) THEN
      result := 4;
    ELSIF(number > 16 AND number <= 32) THEN
      result := 5;
    ELSIF(number > 32 AND number <= 64) THEN
      result := 6;
    ELSIF(number > 64 AND number <= 128) THEN
      result := 7;
    ELSIF(number > 128 AND number <= 256) THEN
      result := 8;
    ELSIF(number > 256 AND number <= 512) THEN
      result := 9;
    ELSIF(number > 512 AND number <= 1024) THEN
      result := 10;
    ELSIF(number > 1024 AND number <= 2048) THEN
      result := 11;
    ELSIF(number > 2048 AND number <= 4096) THEN
      result := 12;
    ELSIF(number > 4096 AND number <= 8192) THEN
      result := 13;
    ELSIF(number > 8192 AND number <= 16384) THEN
      result := 14;
    ELSIF(number > 16384 AND number <= 32768) THEN
      result := 15;
    END IF;
    RETURN result;
  END FUNCTION;

  FUNCTION log2_inf_integer (number : natural) RETURN natural IS
    VARIABLE result : natural;
  BEGIN

    IF(number < 2) THEN
      result := 0;
    ELSIF(number >= 2 AND number < 4) THEN
      result := 1;
    ELSIF(number >= 4 AND number < 8) THEN
      result := 2;
    ELSIF(number >= 8 AND number < 16) THEN
      result := 3;
    ELSIF(number >= 16 AND number < 32) THEN
      result := 4;
    ELSIF(number >= 32 AND number < 64) THEN
      result := 5;
    ELSIF(number >= 64 AND number < 128) THEN
      result := 6;
    ELSIF(number >= 128 AND number < 256) THEN
      result := 7;
    ELSIF(number >= 256 AND number < 512) THEN
      result := 8;
    ELSIF(number >= 512 AND number < 1024) THEN
      result := 9;
    ELSIF(number >= 1024 AND number < 2048) THEN
      result := 10;
    ELSIF(number >= 2048 AND number < 4096) THEN
      Result := 11;
    ELSIF(Number >= 4096 AND number < 8192) THEN
      result := 12;
    ELSIF(number >= 8192 AND number < 16384) THEN
      result := 13;
    ELSIF(number >= 16384 AND number < 32768) THEN
      result := 14;
    END IF;
    RETURN result;
  END FUNCTION;

END PACKAGE BODY;