From 86b8c2e84a065a5cc3d2f960798ca626d391a2f9 Mon Sep 17 00:00:00 2001
From: Eric Kooistra <kooistra@astron.nl>
Date: Tue, 5 Apr 2022 14:46:20 +0200
Subject: [PATCH] Use c_wpfb_lofar2_subbands_dts_18b setting. Use
func_wpfb_subband_gain() to calculate expected subband ampl.
---
.../lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd | 29 +++++++++++++------
1 file changed, 20 insertions(+), 9 deletions(-)
diff --git a/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd b/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd
index faace9dd44..e9e7f6c3ad 100644
--- a/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd
+++ b/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd
@@ -139,26 +139,37 @@ PACKAGE sdp_pkg is
--CONSTANT c_sdp_wpfb_subbands : t_wpfb :=
-- (1, c_sdp_N_fft, 0, c_sdp_P_pfb,
-- c_sdp_N_taps, 1, c_sdp_W_adc, 16, c_sdp_W_fir_coef,
- -- true, false, true, 16, c_sdp_W_subband, 1, 18, 2,
- -- true, 54, 2, 195313, c_fft_pipeline, c_fft_pipeline,
- -- c_fil_ppf_pipeline);
+ -- true, false, true, 16, c_sdp_W_subband, 1, 18, 2, true, 54, 2, 195313,
+ -- c_fft_pipeline, c_fft_pipeline, c_fil_ppf_pipeline);
+
-- LTS 2021-02-03, changes based on results from u_wpfb_stage22 in tb_tb_verify_pfb_wg.vhd:
-- . fil_backoff_w = 0 (was 1)
-- . fil_out_dat_w = fft_in_dat_w = 17 (was 16)
-- . g_fft_out_gain_w = 0 (was 1)
-- . g_fft_stage_dat_w = 22 (was 18)
-- . g_fft_guard_w = 1 (was 2)
+ --CONSTANT c_sdp_wpfb_subbands : t_wpfb :=
+ -- (1, c_sdp_N_fft, 0, c_sdp_P_pfb,
+ -- c_sdp_N_taps, 0, c_sdp_W_adc, 17, c_sdp_W_fir_coef,
+ -- true, false, true, 17, c_sdp_W_subband, 0, 22, 1, true, 54, c_sdp_W_statistic_sz, 195313,
+ -- c_fft_pipeline, c_fft_pipeline, c_fil_ppf_pipeline); -- = c_wpfb_lofar2_subbands_lts_2021
+
+ -- DTS 2022-04-04, changes based on results from in tb_tb_verify_pfb_wg.vhd:
+ -- . fil_backoff_w = 1
+ -- . fil_out_dat_w = fft_in_dat_w = 0 (use g_fft_stage_dat_w - g_fft_guard_w)
+ -- . g_fft_out_gain_w = 1 (compensate for fil_backoff_w = 1)
+ -- . g_fft_stage_dat_w = 24
+ -- . g_fft_guard_w = 1
CONSTANT c_sdp_wpfb_subbands : t_wpfb :=
(1, c_sdp_N_fft, 0, c_sdp_P_pfb,
- c_sdp_N_taps, 0, c_sdp_W_adc, 17, c_sdp_W_fir_coef,
- true, false, true, 17, c_sdp_W_subband, 0, 22, 1,
- true, 54, c_sdp_W_statistic_sz, 195313, c_fft_pipeline, c_fft_pipeline,
- c_fil_ppf_pipeline);
+ c_sdp_N_taps, 1, c_sdp_W_adc, 23, c_sdp_W_fir_coef,
+ true, false, true, 23, c_sdp_W_subband, 1, 24, 1, true, 54, c_sdp_W_statistic_sz, 195313,
+ c_fft_pipeline, c_fft_pipeline, c_fil_ppf_pipeline); -- = c_wpfb_lofar2_subbands_dts_18b
-- 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;
- CONSTANT c_sdp_wpfb_subband_sp_ampl_ratio : REAL := 8.0 * c_sdp_wpfb_fir_filter_dc_gain; -- ~= 8 for unit FIR DC gain, depends on internal WPFB quantization and FIR coefficients
+ CONSTANT c_sdp_wpfb_fir_filter_dc_gain : REAL := c_fil_lofar1_fir_filter_dc_gain; -- = 0.994817, almost unit DC gain
+ CONSTANT c_sdp_wpfb_subband_sp_ampl_ratio : REAL := func_wpfb_subband_gain(c_sdp_wpfb_subbands, c_sdp_wpfb_fir_filter_dc_gain);
-----------------------------------------------------------------------------
-- Statistics offload
--
GitLab