Finish DSSS demodulation stage 1

4 files changed, 68 insertions, 52 deletions

diff --git a/controller/fw/Makefile b/controller/fw/Makefile
index 2c75bbf..3b9cca6 100644
--- a/controller/fw/Makefile
+++ b/controller/fw/Makefile
@@ -51,11 +51,12 @@ FMEAS_SAMPLING_RATE		?= 10.0
 
 DSSS_GOLD_CODE_NBITS 	?= 5
 DSSS_DECIMATION			?= 10
+# TODO maybe auto adjust this based on detection rate?
 DSSS_THESHOLD_FACTOR	?= 5.0f
 DSSS_WAVELET_WIDTH		?= 7.3
 DSSS_WAVELET_LUT_SIZE	?= 69
-DSSS_FILTER_FC			?= 10e-3
-DSSS_FILTER_ORDER		?= 10
+DSSS_FILTER_FC			?= 3e-3
+DSSS_FILTER_ORDER		?= 12
 
 CC			:= $(PREFIX)gcc
 CXX			:= $(PREFIX)g++
diff --git a/controller/fw/src/dsss_demod.c b/controller/fw/src/dsss_demod.c
index 7feb41b..cc1c34e 100644
--- a/controller/fw/src/dsss_demod.c
+++ b/controller/fw/src/dsss_demod.c
@@ -22,70 +22,77 @@ float gold_correlate_step(const size_t ncode, const float a[DSSS_CORRELATION_LEN
 float cwt_convolve_step(const float v[DSSS_WAVELET_LUT_SIZE], size_t offx);
 float run_iir(const float x, const int order, const struct iir_biquad q[order], struct iir_biquad_state st[order]);
 float run_biquad(float x, const struct iir_biquad *const q, struct iir_biquad_state *const restrict st);
+void debug_print_vector(const char *name, size_t len, const float *data, size_t stride, bool index, bool debug);
 
 #ifdef SIMULATION
-void dsss_demod_step(struct dsss_demod_state *st, float new_value, size_t sim_pos) {
-#else /* SIMULATION */
+void debug_print_vector(const char *name, size_t len, const float *data, size_t stride, bool index, bool debug) {
+    if (!debug)
+        return;
+
+    if (index) {
+        DEBUG_PRINTN("    %16s  [", "");
+        for (size_t i=0; i<len; i++)
+            DEBUG_PRINTN("%8d  ", i);
+        DEBUG_PRINTN("]\n");
+    }
+
+    DEBUG_PRINTN("    %16s: [", name);
+    for (size_t i=0; i<len; i++)
+        DEBUG_PRINTN("%8.5f, ", data[i*stride]);
+    DEBUG_PRINTN("]\n");
+}
+#else 
+void debug_print_vector(const char *name, size_t len, const float *data, size_t stride, bool index, bool debug) {}
+#endif
+
+#ifdef SIMULATION
+void dsss_demod_step(struct dsss_demod_state *st, float new_value, size_t sim_pos, int record_channel) {
+    bool debug = (record_channel == -1)
+        && (sim_pos > 1000)
+        && (sim_pos % DSSS_CORRELATION_LENGTH == DSSS_CORRELATION_LENGTH-1);
+
+    if (debug) DEBUG_PRINT("Iteration %zd: signal=%f", sim_pos, new_value);
+#else
 void dsss_demod_step(struct dsss_demod_state *st, float new_value) {
-#endif /* SIMULATION */
+#endif
 
-//#define DEBUG_PRINT(...) ((void)0)
-//#define DEBUG_PRINTN(...) ((void)0)
-    bool debug = sim_pos % DSSS_CORRELATION_LENGTH == DSSS_CORRELATION_LENGTH-1;
-    //bool debug = sim_pos > 1000;
-    if (debug) DEBUG_PRINT("Iteration %zd", sim_pos);
     //const float peak_group_threshold = 0.05 * DSSS_CORRELATION_LENGTH;
     //const float hole_patching_threshold = 0.01 * DSSS_CORRELATION_LENGTH;
 
     st->signal[st->signal_wpos] = new_value;
     st->signal_wpos = (st->signal_wpos + 1) % ARRAY_LENGTH(st->signal);
-    if (debug) DEBUG_PRINT("   signal: %f", new_value);
 
     /* use new, incremented wpos for gold_correlate_step as first element of old data in ring buffer */
     for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
         st->correlation[i][st->correlation_wpos] = gold_correlate_step(i, st->signal, st->signal_wpos, false);
-    /* debug */
-    if (debug) {
-        DEBUG_PRINTN("                 [");
-        for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
-            DEBUG_PRINTN("%8d  ", i);
-        DEBUG_PRINTN("]\n");
-        DEBUG_PRINTN("    correlation: [");
-        for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
-            DEBUG_PRINTN("%8.5f, ", st->correlation[i][st->correlation_wpos]);
-        DEBUG_PRINTN("]\n");
-    }
-    /* end */
+
+    debug_print_vector("correlation",
+            DSSS_GOLD_CODE_COUNT, &st->correlation[0][st->correlation_wpos], DSSS_WAVELET_LUT_SIZE, true, debug);
+
     st->correlation_wpos = (st->correlation_wpos + 1) % ARRAY_LENGTH(st->correlation[0]);
 
     float cwt[DSSS_GOLD_CODE_COUNT];
     for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
         cwt[i] = cwt_convolve_step(st->correlation[i], st->correlation_wpos);
-    /* debug */
-    if (debug) DEBUG_PRINTN("    cwt:         [");
-    for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
-        if (debug) DEBUG_PRINTN("%8.5f, ", cwt[i]);
-    if (debug) DEBUG_PRINTN("]\n");
-    /* end */
+
+    debug_print_vector("cwt", DSSS_GOLD_CODE_COUNT, cwt, 1, false, debug);
 
     float avg[DSSS_GOLD_CODE_COUNT];
     for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
         avg[i] = run_iir(fabs(cwt[i]), ARRAY_LENGTH(cwt_filter_bq), cwt_filter_bq, st->cwt_filter[i].st);
-    /* debug */
-    if (debug) DEBUG_PRINTN("    avg:         [");
-    for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++)
-        if (debug) DEBUG_PRINTN("%8.5f, ", avg[i]);
-    if (debug) DEBUG_PRINTN("]\n");
-    /* end */
+
+    debug_print_vector("avg", DSSS_GOLD_CODE_COUNT, avg, 1, false, debug);
+
+    if (record_channel != -1)
+        DEBUG_PRINTN("%f, %f, %f\n",
+                st->correlation[record_channel][st->correlation_wpos], cwt[record_channel], avg[record_channel]);
 
     float max_val = st->group.max;
     int max_ch = st->group.max_ch;
     int max_idx = st->group.max_idx + 1;
     bool found = false;
-    //if (debug) DEBUG_PRINTN("    rel: [");
     for (size_t i=0; i<DSSS_GOLD_CODE_COUNT; i++) {
         float val = cwt[i] / avg[i];
-        //if (debug) DEBUG_PRINTN("%f, ", val);
 
         if (fabs(val) > DSSS_THESHOLD_FACTOR)
             found = true;
@@ -96,12 +103,6 @@ void dsss_demod_step(struct dsss_demod_state *st, float new_value) {
             max_idx = st->group.len;
         }
     }
-    //if (debug) DEBUG_PRINTN("]\n");
-
-    /* debug */
-    if (debug) DEBUG_PRINT("    found=%d len=%d idx=%d ch=%d max=%f",
-            found, st->group.len, st->group.max_idx, st->group.max_ch, st->group.max);
-    /* end */
 
     if (found) {
         /* Continue ongoing group */
@@ -117,8 +118,9 @@ void dsss_demod_step(struct dsss_demod_state *st, float new_value) {
         return;
 
     /* A group ended. Process result. */
-    DEBUG_PRINT("GROUP FOUND: %8d len=%3d max=%f ch=%d offx=%d",
-            sim_pos, st->group.len, st->group.max, st->group.max_ch, st->group.max_idx);
+    if (record_channel == -1)
+        DEBUG_PRINT("GROUP FOUND: %8d len=%3d max=%f ch=%d offx=%d",
+                sim_pos, st->group.len, st->group.max, st->group.max_ch, st->group.max_idx);
 
     /* reset grouping state */
     st->group.len = 0;
diff --git a/controller/fw/src/dsss_demod.h b/controller/fw/src/dsss_demod.h
index 8ab5cac..b6947bc 100644
--- a/controller/fw/src/dsss_demod.h
+++ b/controller/fw/src/dsss_demod.h
@@ -36,7 +36,7 @@ struct dsss_demod_state {
 };
 
 #ifdef SIMULATION
-void dsss_demod_step(struct dsss_demod_state *st, float new_value, size_t sim_pos);
+void dsss_demod_step(struct dsss_demod_state *st, float new_value, size_t sim_pos, int record_channel);
 #else /* SIMULATION */
 void dsss_demod_step(struct dsss_demod_state *st, float new_value);
 #endif /* SIMULATION */
diff --git a/controller/fw/tools/dsss_demod_test.c b/controller/fw/tools/dsss_demod_test.c
index 51742b1..4370f80 100644
--- a/controller/fw/tools/dsss_demod_test.c
+++ b/controller/fw/tools/dsss_demod_test.c
@@ -13,11 +13,11 @@
 #include "dsss_demod.h"
 
 void print_usage() {
-    fprintf(stderr, "Usage: dsss_demod_test [test_data.bin]\n");
+    fprintf(stderr, "Usage: dsss_demod_test [test_data.bin] [optional recording channel number]\n");
 }
 
 int main(int argc, char **argv) {
-    if (argc != 2) {
+    if (argc != 2 && argc != 3) {
         fprintf(stderr, "Error: Invalid arguments.\n");
         print_usage();
         return 1;
@@ -46,7 +46,18 @@ int main(int argc, char **argv) {
         return 2;
     }
 
-    fprintf(stderr, "Reading %zd samples test data...", st.st_size/sizeof(float));
+    int record_channel = -1;
+    if (argc == 3) {
+        char *endptr;
+        record_channel = strtoul(argv[2], &endptr, 10);
+        if (!endptr || *endptr != '\0') {
+            fprintf(stderr, "Invalid channel number \"%s\"\n", argv[2]);
+            return 1;
+        }
+    }
+
+    if (record_channel != -1)
+        fprintf(stderr, "Reading %zd samples test data...", st.st_size/sizeof(float));
     size_t nread = 0;
     while (nread < st.st_size) {
         ssize_t rc = read(fd, buf, st.st_size - nread);
@@ -66,18 +77,20 @@ int main(int argc, char **argv) {
 
         nread += rc;
     }
-    fprintf(stderr, " done.\n");
+    if (record_channel != -1)
+        fprintf(stderr, " done.\n");
 
     const size_t n_samples = st.st_size / sizeof(float);
     float *buf_f = (float *)buf;
 
-    fprintf(stderr, "Starting simulation.\n");
+    if (record_channel != -1)
+        fprintf(stderr, "Starting simulation.\n");
 
     struct dsss_demod_state demod;
     memset(&demod, 0, sizeof(demod));
     for (size_t i=0; i<n_samples; i++) {
         //fprintf(stderr, "Iteration %zd/%zd\n", i, n_samples);
-        dsss_demod_step(&demod, buf_f[i], i);
+        dsss_demod_step(&demod, buf_f[i], i, record_channel);
     }
 
     return 0;