int main(int argc, char **argv) {
uint32_t cfi;
float cfi_corr;
int n;
if (argc < 3) {
usage(argv[0]);
exit(-1);
}
parse_args(argc,argv);
if (base_init()) {
fprintf(stderr, "Error initializing receiver\n");
exit(-1);
}
n = filesource_read(&fsrc, input_buffer, flen);
lte_fft_run_sf(&fft, input_buffer, fft_buffer);
if (fmatlab) {
fprintf(fmatlab, "infft=");
vec_fprint_c(fmatlab, input_buffer, flen);
fprintf(fmatlab, ";\n");
fprintf(fmatlab, "outfft=");
vec_sc_prod_cfc(fft_buffer, 1000.0, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
vec_fprint_c(fmatlab, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
fprintf(fmatlab, ";\n");
vec_sc_prod_cfc(fft_buffer, 0.001, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
}
/* Get channel estimates for each port */
chest_dl_estimate(&chest, fft_buffer, ce, 0);
INFO("Decoding PCFICH\n", 0);
n = pcfich_decode(&pcfich, fft_buffer, ce, chest_dl_get_noise_estimate(&chest), 0, &cfi, &cfi_corr);
printf("cfi: %d, distance: %f\n", cfi, cfi_corr);
base_free();
if (n < 0) {
fprintf(stderr, "Error decoding PCFICH\n");
exit(-1);
} else if (n == 0) {
printf("Could not decode PCFICH\n");
exit(-1);
} else {
if (cfi_corr > 2.8 && cfi == 1) {
exit(0);
} else {
exit(-1);
}
}
}
int main(int argc, char **argv) {
pbch_mib_t mib;
int n;
if (argc < 3) {
usage(argv[0]);
exit(-1);
}
parse_args(argc,argv);
if (base_init()) {
fprintf(stderr, "Error initializing receiver\n");
exit(-1);
}
n = filesource_read(&fsrc, input_buffer, FLEN);
lte_fft_run_sf(&fft, input_buffer, fft_buffer);
if (fmatlab) {
fprintf(fmatlab, "outfft=");
vec_sc_prod_cfc(fft_buffer, 1000.0, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
vec_fprint_c(fmatlab, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
fprintf(fmatlab, ";\n");
vec_sc_prod_cfc(fft_buffer, 0.001, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
}
/* Get channel estimates for each port */
chest_ce_sf(&chest, fft_buffer, ce, 0);
INFO("Decoding PBCH\n", 0);
n = pbch_decode(&pbch, fft_buffer, ce, &mib);
base_free();
if (n < 0) {
fprintf(stderr, "Error decoding PBCH\n");
exit(-1);
} else if (n == 0) {
printf("Could not decode PBCH\n");
exit(-1);
} else {
if (mib.nof_ports == 2 && mib.nof_prb == 50 && mib.phich_length == PHICH_NORM
&& mib.phich_resources == R_1 && mib.sfn == 28) {
pbch_mib_fprint(stdout, &mib, cell.id);
printf("This is the signal.1.92M.dat file\n");
exit(0);
} else {
pbch_mib_fprint(stdout, &mib, cell.id);
printf("This is an unknown file\n");
exit(-1);
}
}
}
/** 36.211 10.3 section 6.11.1.2
*/
void pss_put_slot(cf_t *pss_signal, cf_t *slot, uint32_t nof_prb, lte_cp_t cp) {
int k;
k = (CP_NSYMB(cp) - 1) * nof_prb * RE_X_RB + nof_prb * RE_X_RB / 2 - 31;
memset(&slot[k - 5], 0, 5 * sizeof(cf_t));
memcpy(&slot[k], pss_signal, PSS_LEN * sizeof(cf_t));
memset(&slot[k + PSS_LEN], 0, 5 * sizeof(cf_t));
}
int chest_init_LTEDL(chest_t *q, lte_cell_t cell) {
int ret;
ret = chest_init(q, cell.nof_prb * RE_X_RB, CP_NSYMB(cell.cp), cell.nof_ports);
if (ret != LIBLTE_SUCCESS) {
return ret;
} else {
return chest_ref_LTEDL(q, cell);
}
}
/** 36.211 10.3 section 6.11.2.2
*/
void sss_put_slot(float *sss, cf_t *slot, uint32_t nof_prb, lte_cp_t cp) {
uint32_t i, k;
k = (CP_NSYMB(cp) - 2) * nof_prb * RE_X_RB + nof_prb * RE_X_RB / 2 - 31;
if (k > 5) {
memset(&slot[k - 5], 0, 5 * sizeof(cf_t));
for (i = 0; i < SSS_LEN; i++) {
__real__ slot[k + i] = sss[i];
__imag__ slot[k + i] = 0;
}
memset(&slot[k + SSS_LEN], 0, 5 * sizeof(cf_t));
}
}
int chest_init(chest_t *q, chest_interp_t interp, lte_cp_t cp, int nof_prb, int nof_ports) {
if (nof_ports > MAX_PORTS) {
fprintf(stderr, "Error: Maximum ports %d\n", MAX_PORTS);
return -1;
}
bzero(q, sizeof(chest_t));
q->nof_ports = nof_ports;
q->nof_symbols = CP_NSYMB(cp);
q->cp = cp;
q->nof_prb = nof_prb;
switch(interp) {
case LINEAR:
q->interp = interp_linear_offset;
}
INFO("Initializing channel estimator size %dx%d, nof_ports=%d\n",
q->nof_symbols, nof_prb, nof_ports);
return 0;
}
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
int i;
lte_cell_t cell;
chest_dl_t chest;
precoding_t cheq;
cf_t *input_signal = NULL, *output_signal[MAX_LAYERS];
cf_t *output_signal2 = NULL;
cf_t *ce[MAX_PORTS];
double *outr0=NULL, *outi0=NULL;
double *outr1=NULL, *outi1=NULL;
double *outr2=NULL, *outi2=NULL;
if (nrhs < NOF_INPUTS) {
help();
return;
}
if (!mxIsDouble(CELLID) && mxGetN(CELLID) != 1 &&
!mxIsDouble(PORTS) && mxGetN(PORTS) != 1 &&
mxGetM(CELLID) != 1) {
help();
return;
}
cell.id = (uint32_t) *((double*) mxGetPr(CELLID));
cell.nof_prb = mxGetM(INPUT)/RE_X_RB;
cell.nof_ports = (uint32_t) *((double*) mxGetPr(PORTS));
if ((mxGetN(INPUT)%14) == 0) {
cell.cp = CPNORM;
} else if ((mxGetN(INPUT)%12)!=0) {
cell.cp = CPEXT;
} else {
mexErrMsgTxt("Invalid number of symbols\n");
help();
return;
}
if (chest_dl_init(&chest, cell)) {
mexErrMsgTxt("Error initiating channel estimator\n");
return;
}
int nsubframes;
if (cell.cp == CPNORM) {
nsubframes = mxGetN(INPUT)/14;
} else {
nsubframes = mxGetN(INPUT)/12;
}
uint32_t sf_idx=0;
if (nsubframes == 1) {
if (nrhs != NOF_INPUTS+1) {
mexErrMsgTxt("Received 1 subframe. Need to provide subframe index.\n");
help();
return;
}
sf_idx = (uint32_t) *((double*) mxGetPr(SFIDX));
} else {
if (nrhs != NOF_INPUTS) {
help();
return;
}
}
uint32_t filter_len = 0;
float *filter;
double *f;
filter_len = mxGetNumberOfElements(FREQ_FILTER);
filter = malloc(sizeof(float) * filter_len);
f = (double*) mxGetPr(FREQ_FILTER);
for (i=0;i<filter_len;i++) {
filter[i] = (float) f[i];
}
chest_dl_set_filter_freq(&chest, filter, filter_len);
filter_len = mxGetNumberOfElements(TIME_FILTER);
filter = malloc(sizeof(float) * filter_len);
f = (double*) mxGetPr(TIME_FILTER);
for (i=0;i<filter_len;i++) {
filter[i] = (float) f[i];
}
chest_dl_set_filter_time(&chest, filter, filter_len);
double *inr=(double *)mxGetPr(INPUT);
double *ini=(double *)mxGetPi(INPUT);
/** Allocate input buffers */
int nof_re = 2*CP_NSYMB(cell.cp)*cell.nof_prb*RE_X_RB;
for (i=0;i<MAX_PORTS;i++) {
ce[i] = vec_malloc(nof_re * sizeof(cf_t));
}
input_signal = vec_malloc(nof_re * sizeof(cf_t));
for (i=0;i<MAX_PORTS;i++) {
output_signal[i] = vec_malloc(nof_re * sizeof(cf_t));
}
output_signal2 = vec_malloc(nof_re * sizeof(cf_t));
precoding_init(&cheq, nof_re);
/* Create output values */
if (nlhs >= 1) {
plhs[0] = mxCreateDoubleMatrix(nof_re * nsubframes, cell.nof_ports, mxCOMPLEX);
outr0 = mxGetPr(plhs[0]);
outi0 = mxGetPi(plhs[0]);
}
if (nlhs >= 2) {
plhs[1] = mxCreateDoubleMatrix(REFSIGNAL_MAX_NUM_SF(cell.nof_prb)*nsubframes, cell.nof_ports, mxCOMPLEX);
outr1 = mxGetPr(plhs[1]);
outi1 = mxGetPi(plhs[1]);
}
if (nlhs >= 3) {
plhs[2] = mxCreateDoubleMatrix(nof_re * nsubframes, 1, mxCOMPLEX);
outr2 = mxGetPr(plhs[2]);
outi2 = mxGetPi(plhs[2]);
}
for (int sf=0;sf<nsubframes;sf++) {
/* Convert input to C complex type */
for (i=0;i<nof_re;i++) {
__real__ input_signal[i] = (float) *inr;
if (ini) {
__imag__ input_signal[i] = (float) *ini;
}
inr++;
ini++;
}
if (nsubframes != 1) {
sf_idx = sf%10;
}
if (chest_dl_estimate(&chest, input_signal, ce, sf_idx)) {
mexErrMsgTxt("Error running channel estimator\n");
return;
}
if (cell.nof_ports == 1) {
predecoding_single(&cheq, input_signal, ce[0], output_signal2, nof_re, chest_dl_get_noise_estimate(&chest));
} else {
predecoding_diversity(&cheq, input_signal, ce, output_signal, cell.nof_ports, nof_re, chest_dl_get_noise_estimate(&chest));
layerdemap_diversity(output_signal, output_signal2, cell.nof_ports, nof_re/cell.nof_ports);
}
if (nlhs >= 1) {
for (int j=0;j<cell.nof_ports;j++) {
for (i=0;i<nof_re;i++) {
*outr0 = (double) crealf(ce[j][i]);
if (outi0) {
*outi0 = (double) cimagf(ce[j][i]);
}
outr0++;
outi0++;
}
}
}
if (nlhs >= 2) {
for (int j=0;j<cell.nof_ports;j++) {
for (i=0;i<REFSIGNAL_NUM_SF(cell.nof_prb,j);i++) {
*outr1 = (double) crealf(chest.pilot_estimates_average[j][i]);
if (outi1) {
*outi1 = (double) cimagf(chest.pilot_estimates_average[j][i]);
}
outr1++;
outi1++;
}
}
}
if (nlhs >= 3) {
for (i=0;i<nof_re;i++) {
*outr2 = (double) crealf(output_signal2[i]);
if (outi2) {
*outi2 = (double) cimagf(output_signal2[i]);
}
outr2++;
outi2++;
}
}
}
if (nlhs >= 4) {
plhs[3] = mxCreateDoubleScalar(chest_dl_get_snr(&chest));
}
if (nlhs >= 5) {
plhs[4] = mxCreateDoubleScalar(chest_dl_get_noise_estimate(&chest));
}
if (nlhs >= 6) {
plhs[5] = mxCreateDoubleScalar(chest_dl_get_rsrp(&chest));
}
chest_dl_free(&chest);
precoding_free(&cheq);
return;
}
int base_init() {
int i;
if (filesource_init(&fsrc, input_file_name, COMPLEX_FLOAT_BIN)) {
fprintf(stderr, "Error opening file %s\n", input_file_name);
exit(-1);
}
if (matlab_file_name) {
fmatlab = fopen(matlab_file_name, "w");
if (!fmatlab) {
perror("fopen");
return -1;
}
} else {
fmatlab = NULL;
}
input_buffer = malloc(FLEN * sizeof(cf_t));
if (!input_buffer) {
perror("malloc");
exit(-1);
}
fft_buffer = malloc(2 * CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB * sizeof(cf_t));
if (!fft_buffer) {
perror("malloc");
return -1;
}
for (i=0;i<cell.nof_ports;i++) {
ce[i] = malloc(2 * CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB * sizeof(cf_t));
if (!ce[i]) {
perror("malloc");
return -1;
}
}
if (!lte_cell_isvalid(&cell)) {
fprintf(stderr, "Invalid cell properties\n");
return -1;
}
if (chest_init_LTEDL(&chest, cell)) {
fprintf(stderr, "Error initializing equalizer\n");
return -1;
}
if (lte_fft_init(&fft, cell.cp, cell.nof_prb)) {
fprintf(stderr, "Error initializing FFT\n");
return -1;
}
if (pbch_init(&pbch, cell)) {
fprintf(stderr, "Error initiating PBCH\n");
return -1;
}
DEBUG("Memory init OK\n",0);
return 0;
}
int main(int argc, char **argv) {
ra_pdsch_t ra_dl;
int i;
int nof_frames;
int ret;
char *data;
dci_location_t locations[10];
uint32_t nof_locations;
dci_msg_t dci_msg;
data = malloc(10000);
if (argc < 3) {
usage(argv[0]);
exit(-1);
}
parse_args(argc,argv);
if (base_init()) {
fprintf(stderr, "Error initializing memory\n");
exit(-1);
}
if (rnti == SIRNTI) {
INFO("Initializing common search space for SI-RNTI\n",0);
nof_locations = pdcch_common_locations(&pdcch, locations, 10, cfi);
} else {
// For ue-specific, generate locations for subframe 5
INFO("Initializing user-specific search space for RNTI: 0x%x\n", rnti);
nof_locations = pdcch_ue_locations(&pdcch, locations, 10, 5, cfi, rnti);
}
ret = -1;
nof_frames = 0;
do {
filesource_read(&fsrc, input_buffer, flen);
if (nof_frames == 5) {
INFO("Reading %d samples sub-frame %d\n", flen, nof_frames);
lte_fft_run_sf(&fft, input_buffer, fft_buffer);
if (fmatlab) {
fprintf(fmatlab, "infft%d=", nof_frames);
vec_fprint_c(fmatlab, input_buffer, flen);
fprintf(fmatlab, ";\n");
fprintf(fmatlab, "outfft%d=", nof_frames);
vec_sc_prod_cfc(fft_buffer, 1000.0, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
vec_fprint_c(fmatlab, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
fprintf(fmatlab, ";\n");
vec_sc_prod_cfc(fft_buffer, 0.001, fft_buffer, CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB);
}
/* Get channel estimates for each port */
for (i=0;i<cell.nof_ports;i++) {
chest_ce_slot_port(&chest, fft_buffer, ce[i], 2*nof_frames, i);
chest_ce_slot_port(&chest, &fft_buffer[CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB],
&ce[i][CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB], 2*nof_frames+1, i);
if (fmatlab) {
chest_fprint(&chest, fmatlab, 2*nof_frames+1, i);
}
}
uint16_t crc_rem = 0;
for (i=0;i<nof_locations && crc_rem != rnti;i++) {
if (pdcch_extract_llr(&pdcch, fft_buffer, ce, locations[i], nof_frames, cfi)) {
fprintf(stderr, "Error extracting LLRs\n");
return -1;
}
if (pdcch_decode_msg(&pdcch, &dci_msg, Format1A, &crc_rem)) {
fprintf(stderr, "Error decoding DCI msg\n");
return -1;
}
}
if (crc_rem == rnti) {
if (dci_msg_to_ra_dl(&dci_msg, rnti, 1234, cell, cfi, &ra_dl)) {
fprintf(stderr, "Error unpacking PDSCH scheduling DCI message\n");
goto goout;
}
if (pdsch_harq_setup(&harq_process, ra_dl.mcs, &ra_dl.prb_alloc)) {
fprintf(stderr, "Error configuring HARQ process\n");
goto goout;
}
if (pdsch_decode(&pdsch, fft_buffer, ce, data, nof_frames%10, &harq_process, ra_dl.rv_idx)) {
fprintf(stderr, "Error decoding PDSCH\n");
goto goout;
} else {
printf("PDSCH Decoded OK!\n");
}
}
}
nof_frames++;
} while (nof_frames <= max_frames);
ret = 0;
goout:
base_free();
exit(ret);
}
int base_init() {
int i;
if (filesource_init(&fsrc, input_file_name, COMPLEX_FLOAT_BIN)) {
fprintf(stderr, "Error opening file %s\n", input_file_name);
exit(-1);
}
if (matlab_file_name) {
fmatlab = fopen(matlab_file_name, "w");
if (!fmatlab) {
perror("fopen");
return -1;
}
} else {
fmatlab = NULL;
}
flen = 2 * (SLOT_LEN(lte_symbol_sz(cell.nof_prb)));
input_buffer = malloc(flen * sizeof(cf_t));
if (!input_buffer) {
perror("malloc");
exit(-1);
}
fft_buffer = malloc(2 * CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB * sizeof(cf_t));
if (!fft_buffer) {
perror("malloc");
return -1;
}
for (i=0;i<MAX_PORTS;i++) {
ce[i] = malloc(2 * CP_NSYMB(cell.cp) * cell.nof_prb * RE_X_RB * sizeof(cf_t));
if (!ce[i]) {
perror("malloc");
return -1;
}
}
if (chest_init_LTEDL(&chest, cell)) {
fprintf(stderr, "Error initializing equalizer\n");
return -1;
}
if (lte_fft_init(&fft, cell.cp, cell.nof_prb)) {
fprintf(stderr, "Error initializing FFT\n");
return -1;
}
if (regs_init(®s, R_1, PHICH_NORM, cell)) {
fprintf(stderr, "Error initiating regs\n");
return -1;
}
if (regs_set_cfi(®s, cfi)) {
fprintf(stderr, "Error setting CFI %d\n", cfi);
return -1;
}
if (pdcch_init(&pdcch, ®s, cell)) {
fprintf(stderr, "Error creating PDCCH object\n");
exit(-1);
}
if (pdsch_init(&pdsch, cell)) {
fprintf(stderr, "Error creating PDSCH object\n");
exit(-1);
}
pdsch_set_rnti(&pdsch, rnti);
if (pdsch_harq_init(&harq_process, &pdsch)) {
fprintf(stderr, "Error initiating HARQ process\n");
exit(-1);
}
DEBUG("Memory init OK\n",0);
return 0;
}
int main(int argc, char **argv) {
chest_t eq;
cf_t *input = NULL, *ce = NULL, *h = NULL;
refsignal_t refs;
int i, j, n_port, n_slot, cid, num_re;
int ret = -1;
int max_cid;
FILE *fmatlab = NULL;
float mse_mag, mse_phase;
parse_args(argc,argv);
if (output_matlab) {
fmatlab=fopen(output_matlab, "w");
if (!fmatlab) {
perror("fopen");
goto do_exit;
}
}
num_re = nof_prb * RE_X_RB * CP_NSYMB(cp);
input = malloc(num_re * sizeof(cf_t));
if (!input) {
perror("malloc");
goto do_exit;
}
h = malloc(num_re * sizeof(cf_t));
if (!h) {
perror("malloc");
goto do_exit;
}
ce = malloc(num_re * sizeof(cf_t));
if (!ce) {
perror("malloc");
goto do_exit;
}
if (cell_id == -1) {
cid = 0;
max_cid = 504;
} else {
cid = cell_id;
max_cid = cell_id;
}
while(cid <= max_cid) {
if (chest_init(&eq, LINEAR, cp, nof_prb, MAX_PORTS)) {
fprintf(stderr, "Error initializing equalizer\n");
goto do_exit;
}
if (chest_ref_LTEDL(&eq, cid)) {
fprintf(stderr, "Error initializing reference signal\n");
goto do_exit;
}
for (n_slot=0;n_slot<NSLOTS_X_FRAME;n_slot++) {
for (n_port=0;n_port<MAX_PORTS;n_port++) {
if (refsignal_init_LTEDL(&refs, n_port, n_slot, cid, cp, nof_prb)) {
fprintf(stderr, "Error initiating CRS slot=%d\n", i);
return -1;
}
bzero(input, sizeof(cf_t) * num_re);
for (i=0;i<num_re;i++) {
input[i] = 0.5-rand()/RAND_MAX+I*(0.5-rand()/RAND_MAX);
}
bzero(ce, sizeof(cf_t) * num_re);
bzero(h, sizeof(cf_t) * num_re);
refsignal_put(&refs, input);
refsignal_free(&refs);
for (i=0;i<CP_NSYMB(cp);i++) {
for (j=0;j<nof_prb * RE_X_RB;j++) {
float x = -1+(float) i/CP_NSYMB(cp) + cosf(2 * M_PI * (float) j/nof_prb/RE_X_RB);
h[i*nof_prb * RE_X_RB+j] = (3+x) * cexpf(I * x);
input[i*nof_prb * RE_X_RB+j] *= h[i*nof_prb * RE_X_RB+j];
}
}
chest_ce_slot_port(&eq, input, ce, n_slot, n_port);
mse_mag = mse_phase = 0;
for (i=0;i<num_re;i++) {
mse_mag += (cabsf(h[i]) - cabsf(ce[i])) * (cabsf(h[i]) - cabsf(ce[i])) / num_re;
mse_phase += (cargf(h[i]) - cargf(ce[i])) * (cargf(h[i]) - cargf(ce[i])) / num_re;
}
if (check_mse(mse_mag, mse_phase, n_port)) {
goto do_exit;
}
if (fmatlab) {
fprintf(fmatlab, "input=");
vec_fprint_c(fmatlab, input, num_re);
fprintf(fmatlab, ";\n");
fprintf(fmatlab, "h=");
vec_fprint_c(fmatlab, h, num_re);
fprintf(fmatlab, ";\n");
fprintf(fmatlab, "ce=");
vec_fprint_c(fmatlab, ce, num_re);
fprintf(fmatlab, ";\n");
chest_fprint(&eq, fmatlab, n_slot, n_port);
}
}
}
chest_free(&eq);
cid+=10;
INFO("cid=%d\n", cid);
}
ret = 0;
do_exit:
if (ce) {
free(ce);
}
if (input) {
free(input);
}
if (h) {
free(h);
}
if (!ret) {
printf("OK\n");
} else {
printf("Error at cid=%d, slot=%d, port=%d\n",cid, n_slot, n_port);
}
exit(ret);
}
int main(int argc, char **argv) {
int distance;
int i, n;
int ngroup, nseq, max_nseq;
char ack_rx;
if (argc < 3) {
usage(argv[0]);
exit(-1);
}
parse_args(argc,argv);
max_nseq = CP_ISNORM(cp)?PHICH_NORM_NSEQUENCES:PHICH_EXT_NSEQUENCES;
if (base_init()) {
fprintf(stderr, "Error initializing memory\n");
exit(-1);
}
n = filesource_read(&fsrc, input_buffer, flen);
lte_fft_run(&fft, input_buffer, fft_buffer);
if (fmatlab) {
fprintf(fmatlab, "infft=");
vec_fprint_c(fmatlab, input_buffer, flen);
fprintf(fmatlab, ";\n");
fprintf(fmatlab, "outfft=");
vec_fprint_c(fmatlab, fft_buffer, CP_NSYMB(cp) * nof_prb * RE_X_RB);
fprintf(fmatlab, ";\n");
}
/* Get channel estimates for each port */
for (i=0;i<nof_ports;i++) {
chest_ce_slot_port(&chest, fft_buffer, ce[i], 0, i);
if (fmatlab) {
chest_fprint(&chest, fmatlab, 0, i);
}
}
INFO("Decoding PHICH\n", 0);
/* Receive all PHICH groups and sequence numbers */
for (ngroup=0;ngroup<phich_ngroups(&phich);ngroup++) {
for (nseq=0;nseq<max_nseq;nseq++) {
if (phich_decode(&phich, fft_buffer, ce, ngroup, nseq, numsubframe, &ack_rx, &distance)<0) {
printf("Error decoding ACK\n");
exit(-1);
}
INFO("%d/%d, ack_rx: %d, ns: %d, distance: %d\n",
ngroup, nseq, ack_rx, numsubframe, distance);
}
}
base_free();
fftwf_cleanup();
if (n < 0) {
fprintf(stderr, "Error decoding phich\n");
exit(-1);
} else if (n == 0) {
printf("Could not decode phich\n");
exit(-1);
} else {
exit(0);
}
}
int base_init() {
int i;
if (filesource_init(&fsrc, input_file_name, COMPLEX_FLOAT_BIN)) {
fprintf(stderr, "Error opening file %s\n", input_file_name);
exit(-1);
}
if (matlab_file_name) {
fmatlab = fopen(matlab_file_name, "w");
if (!fmatlab) {
perror("fopen");
return -1;
}
} else {
fmatlab = NULL;
}
flen = SLOT_LEN(lte_symbol_sz(nof_prb), cp);
input_buffer = malloc(flen * sizeof(cf_t));
if (!input_buffer) {
perror("malloc");
exit(-1);
}
fft_buffer = malloc(CP_NSYMB(cp) * nof_prb * RE_X_RB * sizeof(cf_t));
if (!fft_buffer) {
perror("malloc");
return -1;
}
for (i=0;i<MAX_PORTS_CTRL;i++) {
ce[i] = malloc(CP_NSYMB(cp) * nof_prb * RE_X_RB * sizeof(cf_t));
if (!ce[i]) {
perror("malloc");
return -1;
}
}
if (chest_init(&chest, LINEAR, cp, nof_prb, nof_ports)) {
fprintf(stderr, "Error initializing equalizer\n");
return -1;
}
if (chest_ref_LTEDL(&chest, cell_id)) {
fprintf(stderr, "Error initializing reference signal\n");
return -1;
}
if (lte_fft_init(&fft, cp, nof_prb)) {
fprintf(stderr, "Error initializing FFT\n");
return -1;
}
if (regs_init(®s, cell_id, nof_prb, nof_ports, phich_res, phich_length, cp)) {
fprintf(stderr, "Error initiating regs\n");
return -1;
}
if (phich_init(&phich, ®s, cell_id, nof_prb, nof_ports, cp)) {
fprintf(stderr, "Error creating PBCH object\n");
return -1;
}
DEBUG("Memory init OK\n",0);
return 0;
}
/** Converts the MIB message to symbols mapped to SLOT #1 ready for transmission
*/
int pbch_encode(pbch_t *q, pbch_mib_t *mib, cf_t *sf_symbols[MAX_PORTS]) {
int i;
int nof_bits;
cf_t *slot1_symbols[MAX_PORTS];
cf_t *x[MAX_LAYERS];
if (q != NULL &&
mib != NULL)
{
for (i=0;i<q->cell.nof_ports;i++) {
if (sf_symbols[i] == NULL) {
return LIBLTE_ERROR_INVALID_INPUTS;
} else {
slot1_symbols[i] = &sf_symbols[i][q->cell.nof_prb * RE_X_RB * CP_NSYMB(q->cell.cp)];
}
}
/* Set pointers for layermapping & precoding */
nof_bits = 2 * q->nof_symbols;
/* number of layers equals number of ports */
for (i = 0; i < q->cell.nof_ports; i++) {
x[i] = q->pbch_x[i];
}
memset(&x[q->cell.nof_ports], 0, sizeof(cf_t*) * (MAX_LAYERS - q->cell.nof_ports));
if (q->frame_idx == 0) {
/* pack MIB */
pbch_mib_pack(mib, q->data);
/* encode & modulate */
crc_attach(&q->crc, q->data, 24);
crc_set_mask(q->data, q->cell.nof_ports);
convcoder_encode(&q->encoder, q->data, q->data_enc, 40);
rm_conv_tx(q->data_enc, 120, q->pbch_rm_b, 4 * nof_bits);
}
scrambling_b_offset(&q->seq_pbch, &q->pbch_rm_b[q->frame_idx * nof_bits],
q->frame_idx * nof_bits, nof_bits);
mod_modulate(&q->mod, &q->pbch_rm_b[q->frame_idx * nof_bits], q->pbch_d,
nof_bits);
/* layer mapping & precoding */
if (q->cell.nof_ports > 1) {
layermap_diversity(q->pbch_d, x, q->cell.nof_ports, q->nof_symbols);
precoding_diversity(x, q->pbch_symbols, q->cell.nof_ports,
q->nof_symbols / q->cell.nof_ports);
} else {
memcpy(q->pbch_symbols[0], q->pbch_d, q->nof_symbols * sizeof(cf_t));
}
/* mapping to resource elements */
for (i = 0; i < q->cell.nof_ports; i++) {
pbch_put(q->pbch_symbols[i], slot1_symbols[i], q->cell);
}
q->frame_idx++;
if (q->frame_idx == 4) {
q->frame_idx = 0;
}
return LIBLTE_SUCCESS;
} else {
return LIBLTE_ERROR_INVALID_INPUTS;
}
}
/* Decodes the PBCH channel
*
* The PBCH spans in 40 ms. This function is called every 10 ms. It tries to decode the MIB
* given the symbols of a subframe (1 ms). Successive calls will use more subframes
* to help the decoding process.
*
* Returns 1 if successfully decoded MIB, 0 if not and -1 on error
*/
int pbch_decode(pbch_t *q, cf_t *sf_symbols, cf_t *ce[MAX_PORTS], pbch_mib_t *mib) {
uint32_t src, dst, nb;
uint32_t nant_[3] = { 1, 2, 4 };
uint32_t na, nant;
cf_t *slot1_symbols;
int i;
int nof_bits;
cf_t *x[MAX_LAYERS];
cf_t *ce_slot[MAX_PORTS];
int ret = LIBLTE_ERROR_INVALID_INPUTS;
if (q != NULL &&
sf_symbols != NULL &&
mib != NULL)
{
for (i=0;i<q->cell.nof_ports;i++) {
if (ce[i] == NULL) {
return LIBLTE_ERROR_INVALID_INPUTS;
} else {
ce_slot[i] = &ce[i][q->cell.nof_prb * RE_X_RB * CP_NSYMB(q->cell.cp)];
}
}
slot1_symbols = &sf_symbols[q->cell.nof_prb * RE_X_RB * CP_NSYMB(q->cell.cp)];
/* Set pointers for layermapping & precoding */
nof_bits = 2 * q->nof_symbols;
/* number of layers equals number of ports */
for (i = 0; i < MAX_PORTS; i++) {
x[i] = q->pbch_x[i];
}
memset(&x[MAX_PORTS], 0, sizeof(cf_t*) * (MAX_LAYERS - MAX_PORTS));
/* extract symbols */
if (q->nof_symbols != pbch_get(slot1_symbols, q->pbch_symbols[0], q->cell)) {
fprintf(stderr, "There was an error getting the PBCH symbols\n");
return LIBLTE_ERROR;
}
/* extract channel estimates */
for (i = 0; i < q->cell.nof_ports; i++) {
if (q->nof_symbols != pbch_get(ce_slot[i], q->ce[i], q->cell)) {
fprintf(stderr, "There was an error getting the PBCH symbols\n");
return LIBLTE_ERROR;
}
}
q->frame_idx++;
ret = 0;
/* Try decoding for 1 to cell.nof_ports antennas */
for (na = 0; na < q->cell.nof_ports && !ret; na++) {
nant = nant_[na];
INFO("Trying %d TX antennas with %d frames\n", nant, q->frame_idx);
/* in conctrol channels, only diversity is supported */
if (nant == 1) {
/* no need for layer demapping */
predecoding_single_zf(q->pbch_symbols[0], q->ce[0], q->pbch_d,
q->nof_symbols);
} else {
predecoding_diversity_zf(q->pbch_symbols[0], q->ce, x, nant,
q->nof_symbols);
layerdemap_diversity(x, q->pbch_d, nant, q->nof_symbols / nant);
}
/* demodulate symbols */
demod_soft_sigma_set(&q->demod, 1.0);
demod_soft_demodulate(&q->demod, q->pbch_d,
&q->pbch_llr[nof_bits * (q->frame_idx - 1)], q->nof_symbols);
/* We don't know where the 40 ms begin, so we try all combinations. E.g. if we received
* 4 frames, try 1,2,3,4 individually, 12, 23, 34 in pairs, 123, 234 and finally 1234.
* We know they are ordered.
*
* FIXME: There are unnecessary checks because 2,3,4 have already been processed in the previous
* calls.
*/
for (nb = 0; nb < q->frame_idx && !ret; nb++) {
for (dst = 0; (dst < 4 - nb) && !ret; dst++) {
for (src = 0; src < q->frame_idx - nb && !ret; src++) {
DEBUG("Trying %d blocks at offset %d as subframe mod4 number %d\n",
nb + 1, src, dst);
ret = pbch_decode_frame(q, mib, src, dst, nb + 1, nof_bits, nant);
}
}
}
}
/* If not found, make room for the next packet of radio frame symbols */
if (q->frame_idx == 4) {
memmove(q->pbch_llr, &q->pbch_llr[nof_bits], nof_bits * 3 * sizeof(float));
q->frame_idx = 3;
}
}
return ret;
}
