Added c_sdp_wpfb_fir_filter_dc_gain from MATLAB sim.

applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd

@@ -28,8 +28,9 @@
 -- . See Document: L3 SDP Decision: SDP Parameter definitions.
 --   https://support.astron.nl/confluence/display/L2M/L3+SDP+Decision%3A+SDP+Parameter+definitions
 -------------------------------------------------------------------------------
-LIBRARY ieee, common_lib, rTwoSDF_lib, fft_lib, filter_lib, wpfb_lib;
+LIBRARY IEEE, common_lib, rTwoSDF_lib, fft_lib, filter_lib, wpfb_lib;
 USE IEEE.std_logic_1164.ALL;
+USE IEEE.math_real.ALL;
 USE common_lib.common_pkg.ALL;
 USE common_lib.common_mem_pkg.ALL;
 USE common_lib.common_field_pkg.ALL;
@@ -154,6 +155,10 @@ PACKAGE sdp_pkg is
     true, 54, c_sdp_W_statistic_sz, 195313, c_fft_pipeline, c_fft_pipeline,
     c_fil_ppf_pipeline);
 
+  -- DC gain of WPFB FIR filter obtained from applications/lofar2/model/run_pfir_coef.m using application = 'lofar_subband'
+  -- Not used in RTL, only used in test benches to verify expected suband levels
+  CONSTANT c_sdp_wpfb_fir_filter_dc_gain : REAL := 0.994817;
+
   -----------------------------------------------------------------------------
   -- Statistics offload
   -----------------------------------------------------------------------------