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/*
* Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The OpenAirInterface Software Alliance licenses this file to You under
* the OAI Public License, Version 1.0 (the "License"); you may not use this file
* except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.openairinterface.org/?page_id=698
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*-------------------------------------------------------------------------------
* For more information about the OpenAirInterface (OAI) Software Alliance:
* contact@openairinterface.org
*/
/*
* @defgroup _PHY_MODULATION_
* @ingroup _physical_layer_ref_implementation_
* @{
\section _phy_modulation_ OFDM Modulation Blocks
This section deals with basic functions for OFDM Modulation.
*/
#include "PHY/defs.h"
#include "UTIL/LOG/log.h"
#include "UTIL/LOG/vcd_signal_dumper.h"
//static short temp2[2048*4] __attribute__((aligned(16)));
//#define DEBUG_OFDM_MOD
void normal_prefix_mod(int32_t *txdataF,int32_t *txdata,uint8_t nsymb,LTE_DL_FRAME_PARMS *frame_parms)
{
uint8_t i;
int short_offset=0;
if ((2*nsymb) < frame_parms->symbols_per_tti)
short_offset = 1;
// printf("nsymb %d\n",nsymb);
for (i=0; i<((short_offset)+2*nsymb/frame_parms->symbols_per_tti); i++) {
#ifdef DEBUG_OFDM_MOD
printf("slot i %d (txdata offset %d, txoutput %p)\n",i,(i*(frame_parms->samples_per_tti>>1)),
txdata+(i*(frame_parms->samples_per_tti>>1)));
#endif
PHY_ofdm_mod(txdataF+(i*frame_parms->ofdm_symbol_size*frame_parms->symbols_per_tti>>1), // input
txdata+(i*frame_parms->samples_per_tti>>1), // output
frame_parms->ofdm_symbol_size,
1, // number of symbols
frame_parms->nb_prefix_samples0, // number of prefix samples
CYCLIC_PREFIX);
#ifdef DEBUG_OFDM_MOD
printf("slot i %d (txdata offset %d)\n",i,OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES0+(i*frame_parms->samples_per_tti>>1));
#endif
PHY_ofdm_mod(txdataF+frame_parms->ofdm_symbol_size+(i*frame_parms->ofdm_symbol_size*(frame_parms->symbols_per_tti>>1)), // input
txdata+OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES0+(i*(frame_parms->samples_per_tti>>1)), // output
frame_parms->ofdm_symbol_size,
(short_offset==1) ? 1 :(frame_parms->symbols_per_tti>>1)-1,//6, // number of symbols
frame_parms->nb_prefix_samples, // number of prefix samples
CYCLIC_PREFIX);
}
}
void PHY_ofdm_mod(int *input, /// pointer to complex input
int *output, /// pointer to complex output
int fftsize, /// FFT_SIZE
unsigned char nb_symbols, /// number of OFDM symbols
unsigned short nb_prefix_samples, /// cyclic prefix length
Extension_t etype /// type of extension
)
{
static short temp[2048*4] __attribute__((aligned(32)));
unsigned short i,j;
short k;
volatile int *output_ptr=(int*)0;
int *temp_ptr=(int*)0;
void (*idft)(int16_t *,int16_t *, int);
switch (fftsize) {
case 128:
idft = idft128;
break;
case 256:
idft = idft256;
break;
case 512:
idft = idft512;
break;
case 1024:
idft = idft1024;
break;
case 1536:
idft = idft1536;
break;
case 2048:
idft = idft2048;
break;
default:
idft = idft512;
break;
}
#ifdef DEBUG_OFDM_MOD
printf("[PHY] OFDM mod (size %d,prefix %d) Symbols %d, input %p, output %p\n",
fftsize,nb_prefix_samples,nb_symbols,input,output);
#endif
for (i=0; i<nb_symbols; i++) {
#ifdef DEBUG_OFDM_MOD
printf("[PHY] symbol %d/%d offset %d (%p,%p -> %p)\n",i,nb_symbols,i*fftsize+(i*nb_prefix_samples),input,&input[i*fftsize],&output[(i*fftsize) + ((i)*nb_prefix_samples)]);
#endif
#ifndef __AVX2__
// handle 128-bit alignment for 128-bit SIMD (SSE4,NEON,AltiVEC)
idft((int16_t *)&input[i*fftsize],
(fftsize==128) ? (int16_t *)temp : (int16_t *)&output[(i*fftsize) + ((1+i)*nb_prefix_samples)],
1);
#else
// on AVX2 need 256-bit alignment
idft((int16_t *)&input[i*fftsize],
(fftsize<=512) ? (int16_t *)temp : (int16_t *)&output[(i*fftsize) + ((1+i)*nb_prefix_samples)],
1);
#endif
// Copy to frame buffer with Cyclic Extension
// Note: will have to adjust for synchronization offset!
switch (etype) {
case CYCLIC_PREFIX:
output_ptr = &output[(i*fftsize) + ((1+i)*nb_prefix_samples)];
temp_ptr = (int *)temp;
// msg("Doing cyclic prefix method\n");
#ifndef __AVX2__
if (fftsize==128)
#else
if (fftsize<=512)
#endif
{
for (j=0; j<fftsize ; j++) {
output_ptr[j] = temp_ptr[j];
}
}
j=fftsize;
for (k=-1; k>=-nb_prefix_samples; k--) {
output_ptr[k] = output_ptr[--j];
}
break;
case CYCLIC_SUFFIX:
output_ptr = &output[(i*fftsize)+ (i*nb_prefix_samples)];
temp_ptr = (int *)temp;
// msg("Doing cyclic suffix method\n");
for (j=0; j<fftsize ; j++) {
output_ptr[j] = temp_ptr[2*j];
}
for (j=0; j<nb_prefix_samples; j++)
output_ptr[fftsize+j] = output_ptr[j];
break;
case ZEROS:
break;
case NONE:
// msg("NO EXTENSION!\n");
output_ptr = &output[fftsize];
temp_ptr = (int *)temp;
for (j=0; j<fftsize ; j++) {
output_ptr[j] = temp_ptr[2*j];
}
break;
default:
break;
}
}
}
void do_OFDM_mod(int32_t **txdataF, int32_t **txdata, uint32_t frame,uint16_t next_slot, LTE_DL_FRAME_PARMS *frame_parms)
{
int aa, slot_offset, slot_offset_F;
slot_offset_F = (next_slot)*(frame_parms->ofdm_symbol_size)*((frame_parms->Ncp==1) ? 6 : 7);
slot_offset = (next_slot)*(frame_parms->samples_per_tti>>1);
for (aa=0; aa<frame_parms->nb_antennas_tx; aa++) {
if (is_pmch_subframe(frame,next_slot>>1,frame_parms)) {
if ((next_slot%2)==0) {
LOG_D(PHY,"Frame %d, subframe %d: Doing MBSFN modulation (slot_offset %d)\n",frame,next_slot>>1,slot_offset);
PHY_ofdm_mod(&txdataF[aa][slot_offset_F], // input
&txdata[aa][slot_offset], // output
frame_parms->ofdm_symbol_size,
12, // number of symbols
frame_parms->ofdm_symbol_size>>2, // number of prefix samples
CYCLIC_PREFIX);
if (frame_parms->Ncp == EXTENDED)
PHY_ofdm_mod(&txdataF[aa][slot_offset_F], // input
&txdata[aa][slot_offset], // output
frame_parms->ofdm_symbol_size,
2, // number of symbols
frame_parms->nb_prefix_samples, // number of prefix samples
CYCLIC_PREFIX);
else {
LOG_D(PHY,"Frame %d, subframe %d: Doing PDCCH modulation\n",frame,next_slot>>1);
normal_prefix_mod(&txdataF[aa][slot_offset_F],
&txdata[aa][slot_offset],
2,
frame_parms);
}
}
} else {
if (frame_parms->Ncp == EXTENDED)
PHY_ofdm_mod(&txdataF[aa][slot_offset_F], // input
&txdata[aa][slot_offset], // output
frame_parms->ofdm_symbol_size,
6, // number of symbols
frame_parms->nb_prefix_samples, // number of prefix samples
CYCLIC_PREFIX);
else {
normal_prefix_mod(&txdataF[aa][slot_offset_F],
&txdata[aa][slot_offset],
7,
frame_parms);
}
}
}
}
// OFDM modulation for each symbol
void do_OFDM_mod_symbol(LTE_eNB_COMMON *eNB_common_vars, int eNB_id, uint16_t next_slot, LTE_DL_FRAME_PARMS *frame_parms,int do_precoding)
{
int aa, l, slot_offset, slot_offsetF;
int32_t **txdataF = eNB_common_vars->txdataF[eNB_id];
int32_t **txdataF_BF = eNB_common_vars->txdataF_BF[eNB_id];
int32_t **txdata = eNB_common_vars->txdata[eNB_id];
slot_offset = (next_slot)*(frame_parms->samples_per_tti>>1);
slot_offsetF = (next_slot)*(frame_parms->ofdm_symbol_size)*((frame_parms->Ncp==EXTENDED) ? 6 : 7);
//printf("Thread %d starting ... aa %d (%llu)\n",omp_get_thread_num(),aa,rdtsc());
for (l=0; l<frame_parms->symbols_per_tti>>1; l++) {
for (aa=0; aa<frame_parms->nb_antennas_tx; aa++) {
//printf("do_OFDM_mod_l, slot=%d, l=%d, NUMBER_OF_OFDM_CARRIERS=%d,OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES=%d\n",next_slot, l,NUMBER_OF_OFDM_CARRIERS,OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES);
VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_ENB_BEAM_PRECODING,1);
if (do_precoding==1) beam_precoding(txdataF,txdataF_BF,frame_parms,eNB_common_vars->beam_weights[eNB_id],next_slot,l,aa);
VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_ENB_BEAM_PRECODING,0);
//PMCH case not implemented...
if (frame_parms->Ncp == EXTENDED)
PHY_ofdm_mod((do_precoding == 1)?txdataF_BF[aa]:&txdataF[aa][slot_offsetF+l*frame_parms->ofdm_symbol_size], // input
&txdata[aa][slot_offset+l*OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES], // output
frame_parms->ofdm_symbol_size,
1, // number of symbols
frame_parms->nb_prefix_samples, // number of prefix samples
CYCLIC_PREFIX);
else {
if (l==0) {
PHY_ofdm_mod((do_precoding==1)?txdataF_BF[aa]:&txdataF[aa][slot_offsetF+l*frame_parms->ofdm_symbol_size], // input
&txdata[aa][slot_offset], // output
frame_parms->ofdm_symbol_size,
1, // number of symbols
frame_parms->nb_prefix_samples0, // number of prefix samples
CYCLIC_PREFIX);
} else {
PHY_ofdm_mod((do_precoding==1)?txdataF_BF[aa]:&txdataF[aa][slot_offsetF+l*frame_parms->ofdm_symbol_size], // input
&txdata[aa][slot_offset+OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES0+(l-1)*OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES], // output
frame_parms->ofdm_symbol_size,
1, // number of symbols
frame_parms->nb_prefix_samples, // number of prefix samples
CYCLIC_PREFIX);
/* printf("txdata[%d][%d]=%d\n",aa,slot_offset+OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES0+(l-1)*OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES,txdata[aa][slot_offset+OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES0+(l-1)*OFDM_SYMBOL_SIZE_COMPLEX_SAMPLES]);
* */
}
}
}
}
}