Coding test suite added

- get BlER (block error rate) at different Es/N0 values
szabolor · Aug 28, 2015 · 492cf5e · 492cf5e
1 parent 2876aeb
commit 492cf5e
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diff --git a/smog_ref/v0.2/test/Makefile b/smog_ref/v0.2/test/Makefile
@@ -0,0 +1,17 @@
+CC = gcc
+
+CFLAGS = -Wall -Wextra -O3
+
+LDFLAGS = -L../encode/ -L../decode/ -lencref -ldecref -lm
+
+RM = rm
+AR = ar
+
+
+all: test
+
+test: main.c
+	$(CC) main.c $(LDFLAGS) -o test
+
+clean: 
+	-$(RM) test
diff --git a/smog_ref/v0.2/test/main.c b/smog_ref/v0.2/test/main.c
@@ -0,0 +1,218 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <getopt.h>
+#include <string.h>
+#include <assert.h>
+#include <math.h>
+#include <time.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+#define DEBUG 0
+
+extern void decode_data(uint8_t (*raw)[5200], uint8_t (*data)[256], int8_t (*error)[2]);
+extern void encode_data(uint8_t (*data)[256], uint8_t (*encoded)[650]);
+
+static volatile int run = 1;
+
+struct {
+  uint32_t cases;
+  uint32_t block_error; // when error[0 or 1] is -1 or dec_data != data
+  uint32_t error_count; // the sum of errors of successfully decoded messages
+} stat;
+
+struct timeval start, stop, diff;
+
+double ebn0 = 2;
+
+void print_usage() {
+  printf("SMOG reference coding test suite\n\n");
+  printf(" -c         Continuous mode testing\n");
+  printf(" -e [value] Set the desired Eb/N0 value in dB\n");
+  printf("\n");
+  printf("Hit Ctrl+C to end the test and get the final statistics\n");
+  printf("Hit Ctrl+Z to see the current results\n");
+}
+
+double normal_rand(double mean, double std_dev)
+{
+  double fac,rsq,v1,v2;
+  static double gset;
+  static int iset = 0;
+
+  if (iset) {
+    iset = 0;
+    return mean + std_dev * gset;
+  }
+
+  do {
+    v1 = 2.0 * (double) random() / RAND_MAX - 1;
+    v2 = 2.0 * (double) random() / RAND_MAX - 1;
+    rsq = v1 * v1 + v2 * v2;
+  } while (rsq >= 1.0 || rsq == 0.0);
+
+  fac = sqrt(-2.0 * log(rsq) / rsq);
+  gset = v1 * fac;
+  iset++;
+
+  return mean + std_dev * v2 * fac;
+}
+
+uint8_t addnoise(uint8_t sym, double amp, double gain){
+  double sample;
+
+  sample = 127.5 + gain * normal_rand(sym ? amp : -amp, 1.0);
+
+  if (sample < 0.)
+    sample = 0.;
+  else if (sample > 255.0)
+    sample = 255.0;
+  return (uint8_t) sample;
+}
+
+void generate_random_data(uint8_t (*data)[256]) {
+  uint16_t i;
+
+  for (i=0; i<256; ++i) {
+    (*data)[i] = random() & 0xff;
+  }
+}
+
+uint8_t is_equal(uint8_t (*data)[256], uint8_t (*dec_data)[256]) {
+  uint16_t i;
+
+  // TODO: make much more efficient via int64_t concation and comparation or other method
+  for (i=0; i<256; ++i)
+    if ((*data)[i] != (*dec_data)[i])
+      return 0;
+  return 1;
+}
+
+void stat_init() {
+  stat.cases = 0;
+  stat.block_error = 0;
+  stat.error_count = 0;
+}
+
+void stat_refresh(int8_t (*error)[2], uint8_t equal) {
+  ++stat.cases;
+  if (equal && ((*error)[0] != -1) && ((*error)[1] != -1)) {
+    stat.error_count += (*error)[0];
+    stat.error_count += (*error)[1];
+  } else {
+    ++stat.block_error;
+  }
+}
+
+void stat_print() {
+  timersub(&stop, &start, &diff);
+
+  printf("\n=== Statistics ===\n");
+  printf("Number of processed blocks:                   %8d\n", stat.cases);
+  printf("Block failed to decode or decoded incorretly: %8d\n", stat.block_error);
+  printf("Reed-Solomon code error correction sum:       %8d\n", stat.error_count);
+  printf("Eb/N0 = %.4f\n", ebn0);
+  printf("BlER = %.10e\n", (double) stat.block_error / (double) stat.cases);
+  printf("Time elapsed: %ld.%06ld sec\n", (long int)diff.tv_sec, (long int)diff.tv_usec);
+
+}
+
+void stat_quick_print(int signo) {
+  printf("Case: %6d; Block Error: %6d; BlER: %.10e\n", stat.cases, stat.block_error, (double) stat.block_error / (double) stat.cases);
+}
+
+void stoprun(int signo) {
+  run = 0;
+  gettimeofday(&stop, NULL);
+  printf("Stopping...\n");
+  sleep(0.5);
+  // because of no using locks it could happen, that there's is a half-written stat... :\
+  // try to avoid this by sleeping
+  stat_print();
+  exit(0);
+}
+
+void continuous_test(double ebn0) {
+  uint8_t data[256] = {0};
+  uint8_t encoded[650] = {0};
+  uint8_t bits[5200] = {0};
+  uint8_t dec_data[256] = {0};
+  int8_t error[2] = {0};
+  FILE *fp;
+  uint16_t i;
+
+  // Es/No in dB - Energy per symbol (symbol, like channel bit)
+  double esn0 = ebn0 + 10*log10(1. / 2.);
+
+  // Compute noise voltage. The 0.5 factor accounts for BPSK seeing
+  // only half the noise power, and the sqrt() converts power to
+  // voltage.
+  double gain = 1./sqrt(0.5/pow(10.,esn0/10.));
+
+  gettimeofday(&start, NULL);
+  while (run) {
+    generate_random_data(&data);
+#if (DEBUG >= 1)
+    fp = fopen("data", "wb");
+    fwrite(data, 256, 1, fp);
+    fclose(fp);
+#endif
+
+    encode_data(&data, &encoded);
+
+    // AWGN channel simulation
+    for (i=0; i<5200; ++i) {
+      bits[i] = addnoise(encoded[i>>3] & (1 << (7 - (i & 7))), gain, 32.0);
+    }
+
+    decode_data(&bits, &dec_data, &error);
+#if (DEBUG >= 1)
+    fp = fopen("dec_data", "wb");
+    fwrite(dec_data, 256, 1, fp);
+    fclose(fp);
+#endif
+
+    stat_refresh(&error, is_equal(&data, &dec_data));
+  }
+}
+
+int main(int argc, char *argv[]) {
+  char mode = '\0';
+  int option = 0;
+
+  srand(time(NULL));
+  stat_init();
+
+  // Ctrl+C: stop program:
+  signal(SIGINT, stoprun);
+  // Ctrl+Z: quick review of state
+  signal(SIGTSTP, stat_quick_print);
+
+  while ((option = getopt(argc, argv, "ce:")) != -1) {
+    switch (option) {
+      case 'c':
+        mode = 'c';
+        break;
+      case 'e':
+        ebn0 = atof(optarg);
+        break;
+      default:
+        print_usage();
+        exit(1);
+    }
+  }
+
+  switch (mode) {
+    case 'c':
+      continuous_test(ebn0);
+      break;
+    default:
+      printf("No mode have selected!\n");
+      print_usage();
+      exit(0);
+  }
+
+  return 0;
+}
diff --git a/smog_ref/v0.2/test/results.txt b/smog_ref/v0.2/test/results.txt
@@ -0,0 +1,13 @@
+Results:
+EbN0 - BlER (block error rate)
+2.0, 1.012e-5
+1.9, 5.886e-5
+1.8, 1.485e-4
+1.7, 8.222e-4
+1.6, 3.550e-3
+1.5, 9.722e-3
+1.4, 2.879e-2
+1.3, 6.650e-2
+1.2, 1.429e-1
+1.1, 2.678e-1
+1.0, 4.218e-1