// helper function (compare structured object to ordinal computation)
void runtest_dotprod_cccf(unsigned int _n)
{
float tol = 1e-3;
float complex h[_n];
float complex x[_n];
// generate random coefficients
unsigned int i;
for (i=0; i<_n; i++) {
h[i] = randnf() + randnf() * _Complex_I;
x[i] = randnf() + randnf() * _Complex_I;
}
// compute expected value (ordinal computation)
float complex y_test;
dotprod_cccf_run(h, x, _n, &y_test);
// create and run dot product object
float complex y;
dotprod_cccf dp;
dp = dotprod_cccf_create(h,_n);
dotprod_cccf_execute(dp, x, &y);
dotprod_cccf_destroy(dp);
// print results
if (liquid_autotest_verbose) {
printf(" dotprod-cccf-%-4u : %12.8f + j%12.8f (expected %12.8f + j%12.8f)\n",
_n, crealf(y), cimagf(y), crealf(y_test), cimagf(y_test));
}
// validate result
CONTEND_DELTA(crealf(y), crealf(y_test), tol);
CONTEND_DELTA(cimagf(y), cimagf(y_test), tol);
}
// re-create the structured dotprod object
dotprod_cccf dotprod_cccf_recreate(dotprod_cccf _q,
float complex * _h,
unsigned int _n)
{
// completely destroy and re-create dotprod object
dotprod_cccf_destroy(_q);
return dotprod_cccf_create(_h,_n);
}
//
// AUTOTEST: dot product with floating-point data
//
void autotest_dotprod_cccf_rand16()
{
float complex h[16] = {
0.17702709 + 1.38978455*_Complex_I, 0.91294148 + 0.39217381*_Complex_I,
-0.80607338 + 0.76477512*_Complex_I, 0.05099755 + -0.87350051*_Complex_I,
0.44513826 + -0.49490569*_Complex_I, 0.14754967 + 2.04349962*_Complex_I,
1.07246623 + 1.08146290*_Complex_I, -1.14028088 + 1.83380899*_Complex_I,
0.38105361 + -0.45591846*_Complex_I, 0.32605401 + 0.34440081*_Complex_I,
-0.05477144 + 0.60832595*_Complex_I, 1.81667523 + -1.12238075*_Complex_I,
-0.87190497 + 1.10743858*_Complex_I, 1.30921403 + 1.24438643*_Complex_I,
0.55524695 + -1.94931519*_Complex_I, -0.87191170 + 0.91693119*_Complex_I,
};
float complex x[16] = {
-2.19591953 + -0.93229692*_Complex_I, 0.17150376 + 0.56165114*_Complex_I,
1.58354529 + -0.50696037*_Complex_I, 1.40929619 + 0.87868803*_Complex_I,
-0.75505072 + -0.30867372*_Complex_I, -0.09821367 + -0.73949106*_Complex_I,
0.03785571 + 0.72763665*_Complex_I, -1.20262636 + -0.88838102*_Complex_I,
0.23323685 + 0.12456235*_Complex_I, 0.34593736 + 0.02529594*_Complex_I,
0.33669564 + 0.39064649*_Complex_I, -2.45003867 + -0.54862205*_Complex_I,
-2.64870707 + 2.33444473*_Complex_I, -0.92284477 + -2.45121397*_Complex_I,
0.24852918 + -0.62409860*_Complex_I, -0.87039907 + 0.90921212*_Complex_I,
};
float complex y;
float complex test = -0.604285042605890 - 12.390925785344704 * _Complex_I;
float tol = 1e-3f;
dotprod_cccf_run(h,x,16,&y);
CONTEND_DELTA( crealf(y), crealf(test), tol);
CONTEND_DELTA( cimagf(y), cimagf(test), tol);
dotprod_cccf_run4(h,x,16,&y);
CONTEND_DELTA( crealf(y), crealf(test), tol);
CONTEND_DELTA( cimagf(y), cimagf(test), tol);
// test object
dotprod_cccf q = dotprod_cccf_create(h,16);
dotprod_cccf_execute(q,x,&y);
CONTEND_DELTA( crealf(y), crealf(test), tol);
CONTEND_DELTA( cimagf(y), cimagf(test), tol);
dotprod_cccf_destroy(q);
}
int main() {
// options
unsigned int num_channels=64; // must be even number
unsigned int num_symbols=16; // number of symbols
unsigned int m=3; // filter delay (symbols)
float beta = 0.9f; // filter excess bandwidth factor
float phi = 0.0f; // carrier phase offset;
float dphi = 0.04f; // carrier frequency offset
// number of frames (compensate for filter delay)
unsigned int num_frames = num_symbols + 2*m;
unsigned int num_samples = num_channels * num_frames;
unsigned int i;
unsigned int j;
// create filter prototype
unsigned int h_len = 2*num_channels*m + 1;
float h[h_len];
float complex hc[h_len];
float complex gc[h_len];
liquid_firdes_rkaiser(num_channels, m, beta, 0.0f, h);
unsigned int g_len = 2*num_channels*m;
for (i=0; i<g_len; i++) {
hc[i] = h[i];
gc[i] = h[g_len-i-1] * cexpf(_Complex_I*dphi*i);
}
// data arrays
float complex s[num_channels]; // input symbols
float complex y[num_samples]; // time-domain samples
float complex Y0[num_frames][num_channels]; // channelized output
float complex Y1[num_frames][num_channels]; // channelized output
// create ofdm/oqam generator object and generate data
ofdmoqam qs = ofdmoqam_create(num_channels, m, beta, 0.0f, LIQUID_SYNTHESIZER, 0);
for (i=0; i<num_frames; i++) {
for (j=0; j<num_channels; j++) {
if (i<num_symbols) {
#if 0
// QPSK on all subcarriers
s[j] = (rand() % 2 ? 1.0f : -1.0f) +
(rand() % 2 ? 1.0f : -1.0f) * _Complex_I;
s[j] *= 1.0f / sqrtf(2.0f);
#else
// BPSK on even subcarriers
s[j] = rand() % 2 ? 1.0f : -1.0f;
s[j] *= (j%2)==0 ? 1.0f : 0.0f;
#endif
} else {
s[j] = 0.0f;
}
}
// run synthesizer
ofdmoqam_execute(qs, s, &y[i*num_channels]);
}
ofdmoqam_destroy(qs);
// channel
for (i=0; i<num_samples; i++)
y[i] *= cexpf(_Complex_I*(phi + dphi*i));
//
// analysis filterbank (receiver)
//
// create filterbank manually
dotprod_cccf dp[num_channels]; // vector dot products
windowcf w[num_channels]; // window buffers
#if DEBUG
// print coefficients
printf("h_prototype:\n");
for (i=0; i<h_len; i++)
printf(" h[%3u] = %12.8f\n", i, h[i]);
#endif
// create objects
unsigned int gc_sub_len = 2*m;
float complex gc_sub[gc_sub_len];
for (i=0; i<num_channels; i++) {
// sub-sample prototype filter, loading coefficients in
// reverse order
#if 0
for (j=0; j<gc_sub_len; j++)
gc_sub[j] = h[j*num_channels+i];
#else
for (j=0; j<gc_sub_len; j++)
gc_sub[gc_sub_len-j-1] = gc[j*num_channels+i];
#endif
// create window buffer and dotprod objects
dp[i] = dotprod_cccf_create(gc_sub, gc_sub_len);
w[i] = windowcf_create(gc_sub_len);
#if DEBUG
printf("gc_sub[%u] : \n", i);
for (j=0; j<gc_sub_len; j++)
printf(" g[%3u] = %12.8f + %12.8f\n", j, crealf(gc_sub[j]), cimagf(gc_sub[j]));
#endif
}
// generate DFT object
float complex x[num_channels]; // time-domain buffer
float complex X[num_channels]; // freq-domain buffer
#if 0
fftplan fft = fft_create_plan(num_channels, X, x, FFT_REVERSE, 0);
#else
fftplan fft = fft_create_plan(num_channels, X, x, FFT_FORWARD, 0);
#endif
//
// run analysis filter bank
//
#if 0
unsigned int filter_index = 0;
#else
unsigned int filter_index = num_channels-1;
#endif
float complex y_hat; // input sample
float complex * r; // read pointer
for (i=0; i<num_frames; i++) {
// load buffers
for (j=0; j<num_channels; j++) {
// grab sample
y_hat = y[i*num_channels + j];
// push sample into buffer at filter index
windowcf_push(w[filter_index], y_hat);
// decrement filter index
filter_index = (filter_index + num_channels - 1) % num_channels;
//filter_index = (filter_index + 1) % num_channels;
}
// execute filter outputs, reversing order of output (not
// sure why this is necessary)
for (j=0; j<num_channels; j++) {
windowcf_read(w[j], &r);
dotprod_cccf_execute(dp[j], r, &X[num_channels-j-1]);
}
#if 1
// compensate for carrier frequency offset (before transform)
for (j=0; j<num_channels; j++) {
X[j] *= cexpf(-_Complex_I*(dphi*i*num_channels));
}
#endif
// execute DFT, store result in buffer 'x'
fft_execute(fft);
#if 0
// compensate for carrier frequency offset (after transform)
for (j=0; j<num_channels; j++) {
x[j] *= cexpf(-_Complex_I*(dphi*i*num_channels));
}
#endif
// move to output array
for (j=0; j<num_channels; j++)
Y0[i][j] = x[j];
}
// destroy objects
for (i=0; i<num_channels; i++) {
dotprod_cccf_destroy(dp[i]);
windowcf_destroy(w[i]);
}
fft_destroy_plan(fft);
#if 0
// print filterbank channelizer
printf("\n");
printf("filterbank channelizer:\n");
for (i=0; i<num_symbols; i++) {
printf("%3u: ", i);
for (j=0; j<num_channels; j++) {
printf(" %8.5f+j%8.5f, ", crealf(Y0[i][j]), cimagf(Y0[i][j]));
}
printf("\n");
}
#endif
//
// export data
//
FILE*fid = fopen(OUTPUT_FILENAME,"w");
fprintf(fid,"%% %s: auto-generated file\n\n", OUTPUT_FILENAME);
fprintf(fid,"clear all;\nclose all;\n\n");
fprintf(fid,"num_channels=%u;\n", num_channels);
fprintf(fid,"num_symbols=%u;\n", num_symbols);
fprintf(fid,"num_frames = %u;\n", num_frames);
fprintf(fid,"num_samples = num_frames*num_channels;\n");
fprintf(fid,"y = zeros(1,%u);\n", num_samples);
fprintf(fid,"Y0 = zeros(%u,%u);\n", num_frames, num_channels);
fprintf(fid,"Y1 = zeros(%u,%u);\n", num_frames, num_channels);
for (i=0; i<num_frames; i++) {
for (j=0; j<num_channels; j++) {
fprintf(fid,"Y0(%4u,%4u) = %12.4e + j*%12.4e;\n", i+1, j+1, crealf(Y0[i][j]), cimagf(Y0[i][j]));
fprintf(fid,"Y1(%4u,%4u) = %12.4e + j*%12.4e;\n", i+1, j+1, crealf(Y1[i][j]), cimagf(Y1[i][j]));
}
}
// plot BPSK results
fprintf(fid,"figure;\n");
fprintf(fid,"plot(Y0(:,1:2:end),'x');\n");
fprintf(fid,"axis([-1 1 -1 1]*1.2*sqrt(num_channels));\n");
fprintf(fid,"axis square;\n");
fprintf(fid,"grid on;\n");
fclose(fid);
printf("results written to '%s'\n", OUTPUT_FILENAME);
printf("done.\n");
return 0;
}
//
// AUTOTEST: structured dot product, odd lengths
//
void autotest_dotprod_cccf_struct_lengths()
{
float tol = 2e-6;
float complex y;
float complex h[35] = {
1.11555653 + 2.30658043*_Complex_I, -0.36133676 + -0.10917327*_Complex_I,
0.17714505 + -2.14631440*_Complex_I, 2.20424609 + 0.59063608*_Complex_I,
-0.44699194 + 0.23369318*_Complex_I, 0.60613931 + 0.21868288*_Complex_I,
-1.18746289 + -0.52159563*_Complex_I, -0.46277775 + 0.75010157*_Complex_I,
0.93796307 + 0.28608151*_Complex_I, -2.18699829 + 0.38029319*_Complex_I,
0.16145611 + 0.18343353*_Complex_I, -0.62653631 + -1.79037656*_Complex_I,
-0.67042462 + 0.11044084*_Complex_I, 0.70333438 + 1.78729174*_Complex_I,
-0.32923580 + 0.78514690*_Complex_I, 0.27534332 + -0.56377431*_Complex_I,
0.41492559 + 1.37176526*_Complex_I, 3.25368958 + 2.70495218*_Complex_I,
1.63002035 + -0.14193750*_Complex_I, 2.22057186 + 0.55056461*_Complex_I,
1.40896777 + 0.80722903*_Complex_I, -0.22334033 + -0.14227395*_Complex_I,
-1.48631186 + 0.53610531*_Complex_I, -1.91632185 + 0.88755083*_Complex_I,
-0.52054895 + -0.35572001*_Complex_I, -1.56515607 + -0.41448794*_Complex_I,
-0.91107117 + 0.17059659*_Complex_I, -0.77007659 + 2.73381816*_Complex_I,
-0.46645585 + 0.38994666*_Complex_I, 0.80317663 + -0.41756968*_Complex_I,
0.26992512 + 0.41828145*_Complex_I, -0.72456446 + 1.25002030*_Complex_I,
1.19573306 + 0.98449546*_Complex_I, 1.42491943 + -0.55426305*_Complex_I,
1.08243614 + 0.35774368*_Complex_I, };
float complex x[35] = {
-0.82466736 + -1.39329228*_Complex_I, -1.46176052 + -1.96218827*_Complex_I,
-1.28388174 + -0.07152934*_Complex_I, -0.51910014 + -0.37915971*_Complex_I,
-0.65964708 + -0.98417534*_Complex_I, -1.40213479 + -0.82198463*_Complex_I,
0.86051446 + 0.97926463*_Complex_I, 0.26257342 + 0.76586696*_Complex_I,
0.72174183 + -1.89884636*_Complex_I, -0.26018863 + 1.06920599*_Complex_I,
0.57949117 + -0.77431546*_Complex_I, 0.84635184 + -0.81123009*_Complex_I,
-1.12637629 + -0.42027412*_Complex_I, -1.04214881 + 0.90519721*_Complex_I,
0.54458433 + -1.03487314*_Complex_I, -0.17847893 + 2.20358978*_Complex_I,
0.19642532 + -0.07449796*_Complex_I, -1.84958229 + 0.13218920*_Complex_I,
-1.49042886 + 0.81610408*_Complex_I, -0.27466940 + -1.48438409*_Complex_I,
0.29239375 + 0.72443343*_Complex_I, -1.20243456 + -2.77032750*_Complex_I,
-0.41784260 + 0.77455254*_Complex_I, 0.37737465 + -0.52426993*_Complex_I,
-1.25500377 + 1.76270122*_Complex_I, 1.55976056 + -1.18189171*_Complex_I,
-0.05111343 + -1.18849396*_Complex_I, -1.92966664 + 0.66504899*_Complex_I,
-2.82387897 + 1.41128242*_Complex_I, -1.48171326 + -0.03347470*_Complex_I,
0.38047273 + -1.40969799*_Complex_I, 1.71995272 + 0.00298203*_Complex_I,
0.56040910 + -0.12713027*_Complex_I, -0.46653022 + -0.65450499*_Complex_I,
0.15515755 + 1.58944030*_Complex_I, };
float complex v32 = -11.5100903519506 - 15.3575526884014*_Complex_I;
float complex v33 = -10.7148314918614 - 14.9578463360225*_Complex_I;
float complex v34 = -11.7423673921916 - 15.6318827515320*_Complex_I;
float complex v35 = -12.1430314741466 - 13.8559085000689*_Complex_I;
//
dotprod_cccf dp;
// n = 32
dp = dotprod_cccf_create(h,32);
dotprod_cccf_execute(dp, x, &y);
CONTEND_DELTA(y, v32, tol);
dotprod_cccf_destroy(dp);
if (liquid_autotest_verbose) {
printf(" dotprod-cccf-32 : %12.8f + j%12.8f (expected %12.8f + j%12.8f)\n",
crealf(y), cimagf(y), crealf(v32), cimagf(v32));
}
// n = 33
dp = dotprod_cccf_create(h,33);
dotprod_cccf_execute(dp, x, &y);
CONTEND_DELTA(y, v33, tol);
dotprod_cccf_destroy(dp);
if (liquid_autotest_verbose) {
printf(" dotprod-cccf-33 : %12.8f + j%12.8f (expected %12.8f + j%12.8f)\n",
crealf(y), cimagf(y), crealf(v33), cimagf(v33));
}
// n = 34
dp = dotprod_cccf_create(h,34);
dotprod_cccf_execute(dp, x, &y);
CONTEND_DELTA(y, v34, tol);
dotprod_cccf_destroy(dp);
if (liquid_autotest_verbose) {
printf(" dotprod-cccf-34 : %12.8f + j%12.8f (expected %12.8f + j%12.8f)\n",
crealf(y), cimagf(y), crealf(v34), cimagf(v34));
}
// n = 35
dp = dotprod_cccf_create(h,35);
dotprod_cccf_execute(dp, x, &y);
CONTEND_DELTA(y, v35, tol);
dotprod_cccf_destroy(dp);
if (liquid_autotest_verbose) {
printf(" dotprod-cccf-35 : %12.8f + j%12.8f (expected %12.8f + j%12.8f)\n",
crealf(y), cimagf(y), crealf(v35), cimagf(v35));
}
}
