/* Computes channel estimates for each reference in a slot for all ports.
*/
int chest_ce_slot(chest_t *q, cf_t *input, cf_t **ce, uint32_t nslot) {
int p, ret;
for (p=0;p<q->nof_ports;p++) {
ret = chest_ce_slot_port(q, input, ce[p], nslot, p);
if (ret != LIBLTE_SUCCESS) {
return ret;
}
}
return LIBLTE_SUCCESS;
}
/* Computes channel estimates for each reference in a subframe and port id.
*/
int chest_ce_sf_port(chest_t *q, cf_t *input, cf_t *ce, uint32_t sf_idx, uint32_t port_id) {
int n, slotsz, ret;
slotsz = q->nof_symbols*q->nof_re;
for (n=0;n<2;n++) {
ret = chest_ce_slot_port(q, &input[n*slotsz], &ce[n*slotsz], 2*sf_idx+n, port_id);
if (ret != LIBLTE_SUCCESS) {
return ret;
}
}
return LIBLTE_SUCCESS;
}
/* Computes channel estimates for each reference in a subframe for all ports.
*/
int chest_ce_sf(chest_t *q, cf_t *input, cf_t *ce[MAX_PORTS], uint32_t sf_idx) {
int p, n, slotsz, ret;
slotsz = q->nof_symbols*q->nof_re;
for (p=0;p<q->nof_ports;p++) {
for (n=0;n<2;n++) {
ret = chest_ce_slot_port(q, &input[n*slotsz], &ce[p][n*slotsz], 2*sf_idx+n, p);
if (ret != LIBLTE_SUCCESS) {
return ret;
}
}
}
return LIBLTE_SUCCESS;
}
/** This function must be called in an slot basis (0.5ms) for LTE */
int chest_work(chest_hl* hl) {
int i;
chest_t *q = &hl->obj;
if (hl->init.cell_id != hl->ctrl_in.cell_id) {
if (chest_ref_LTEDL(q, hl->init.cell_id)) {
fprintf(stderr, "Error initializing reference signal\n");
return -1;
}
}
for (i=0;i<hl->init.nof_ports;i++) {
chest_ce_slot_port(q, hl->input, hl->output[i], 1, 0);
hl->out_len[i] = hl->in_len;
}
return 0;
}
/* Computes channel estimates for each reference in a slot.
* Saves the result for the p-th port to the pointer ce[p]
*/
void chest_ce_slot(chest_t *q, cf_t *input, cf_t **ce, int nslot) {
int p;
for (p=0;p<q->nof_ports;p++) {
chest_ce_slot_port(q, input, ce[p], nslot, p);
}
}
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 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);
}
}
