lte_ul_channel_estimation.c 40.6 KB
Newer Older
ghaddab's avatar
ghaddab committed
1
/*******************************************************************************
2
    OpenAirInterface
ghaddab's avatar
ghaddab committed
3 4 5 6 7 8 9 10 11 12 13 14 15 16
    Copyright(c) 1999 - 2014 Eurecom

    OpenAirInterface is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.


    OpenAirInterface is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
17 18
    along with OpenAirInterface.The full GNU General Public License is
   included in this distribution in the file called "COPYING". If not,
ghaddab's avatar
ghaddab committed
19 20 21 22 23 24
   see <http://www.gnu.org/licenses/>.

  Contact Information
  OpenAirInterface Admin: openair_admin@eurecom.fr
  OpenAirInterface Tech : openair_tech@eurecom.fr
  OpenAirInterface Dev  : openair4g-devel@eurecom.fr
25

ghaddab's avatar
ghaddab committed
26
  Address      : Eurecom, Campus SophiaTech, 450 Route des Chappes, CS 50193 - 06904 Biot Sophia Antipolis cedex, FRANCE
ghaddab's avatar
ghaddab committed
27 28

 *******************************************************************************/
29 30
#include "PHY/defs.h"
#include "PHY/extern.h"
31
#include "PHY/sse_intrin.h"
32 33 34 35
//#define DEBUG_CH


// For Channel Estimation in Distributed Alamouti Scheme
gauthier's avatar
gauthier committed
36 37 38 39 40
//static int16_t temp_out_ifft[2048*4] __attribute__((aligned(16)));
static int16_t temp_out_fft_0[2048*4] __attribute__((aligned(16)));
static int16_t temp_out_fft_1[2048*4] __attribute__((aligned(16)));
static int16_t temp_out_ifft_0[2048*4] __attribute__((aligned(16)));
static int16_t temp_out_ifft_1[2048*4] __attribute__((aligned(16)));
41 42


gauthier's avatar
gauthier committed
43 44 45 46
static int32_t temp_in_ifft_0[2048*2] __attribute__((aligned(16)));
static int32_t temp_in_ifft_1[2048*2] __attribute__((aligned(16)));
static int32_t temp_in_fft_0[2048*2] __attribute__((aligned(16)));
static int32_t temp_in_fft_1[2048*2] __attribute__((aligned(16)));
47 48

// round(exp(sqrt(-1)*(pi/2)*[0:1:N-1]/N)*pow2(15))
gauthier's avatar
gauthier committed
49
static int16_t ru_90[2*128] = {32767, 0,32766, 402,32758, 804,32746, 1206,32729, 1608,32706, 2009,32679, 2411,32647, 2811,32610, 3212,32568, 3612,32522, 4011,32470, 4410,32413, 4808,32352, 5205,32286, 5602,32214, 5998,32138, 6393,32058, 6787,31972, 7180,31881, 7571,31786, 7962,31686, 8351,31581, 8740,31471, 9127,31357, 9512,31238, 9896,31114, 10279,30986, 10660,30853, 11039,30715, 11417,30572, 11793,30425, 12167,30274, 12540,30118, 12910,29957, 13279,29792, 13646,29622, 14010,29448, 14373,29269, 14733,29086, 15091,28899, 15447,28707, 15800,28511, 16151,28311, 16500,28106, 16846,27897, 17190,27684, 17531,27467, 17869,27246, 18205,27020, 18538,26791, 18868,26557, 19195,26320, 19520,26078, 19841,25833, 20160,25583, 20475,25330, 20788,25073, 21097,24812, 21403,24548, 21706,24279, 22006,24008, 22302,23732, 22595,23453, 22884,23170, 23170,22884, 23453,22595, 23732,22302, 24008,22006, 24279,21706, 24548,21403, 24812,21097, 25073,20788, 25330,20475, 25583,20160, 25833,19841, 26078,19520, 26320,19195, 26557,18868, 26791,18538, 27020,18205, 27246,17869, 27467,17531, 27684,17190, 27897,16846, 28106,16500, 28311,16151, 28511,15800, 28707,15447, 28899,15091, 29086,14733, 29269,14373, 29448,14010, 29622,13646, 29792,13279, 29957,12910, 30118,12540, 30274,12167, 30425,11793, 30572,11417, 30715,11039, 30853,10660, 30986,10279, 31114,9896, 31238,9512, 31357,9127, 31471,8740, 31581,8351, 31686,7962, 31786,7571, 31881,7180, 31972,6787, 32058,6393, 32138,5998, 32214,5602, 32286,5205, 32352,4808, 32413,4410, 32470,4011, 32522,3612, 32568,3212, 32610,2811, 32647,2411, 32679,2009, 32706,1608, 32729,1206, 32746,804, 32758,402, 32766};
50

gauthier's avatar
gauthier committed
51
static int16_t ru_90c[2*128] = {32767, 0,32766, -402,32758, -804,32746, -1206,32729, -1608,32706, -2009,32679, -2411,32647, -2811,32610, -3212,32568, -3612,32522, -4011,32470, -4410,32413, -4808,32352, -5205,32286, -5602,32214, -5998,32138, -6393,32058, -6787,31972, -7180,31881, -7571,31786, -7962,31686, -8351,31581, -8740,31471, -9127,31357, -9512,31238, -9896,31114, -10279,30986, -10660,30853, -11039,30715, -11417,30572, -11793,30425, -12167,30274, -12540,30118, -12910,29957, -13279,29792, -13646,29622, -14010,29448, -14373,29269, -14733,29086, -15091,28899, -15447,28707, -15800,28511, -16151,28311, -16500,28106, -16846,27897, -17190,27684, -17531,27467, -17869,27246, -18205,27020, -18538,26791, -18868,26557, -19195,26320, -19520,26078, -19841,25833, -20160,25583, -20475,25330, -20788,25073, -21097,24812, -21403,24548, -21706,24279, -22006,24008, -22302,23732, -22595,23453, -22884,23170, -23170,22884, -23453,22595, -23732,22302, -24008,22006, -24279,21706, -24548,21403, -24812,21097, -25073,20788, -25330,20475, -25583,20160, -25833,19841, -26078,19520, -26320,19195, -26557,18868, -26791,18538, -27020,18205, -27246,17869, -27467,17531, -27684,17190, -27897,16846, -28106,16500, -28311,16151, -28511,15800, -28707,15447, -28899,15091, -29086,14733, -29269,14373, -29448,14010, -29622,13646, -29792,13279, -29957,12910, -30118,12540, -30274,12167, -30425,11793, -30572,11417, -30715,11039, -30853,10660, -30986,10279, -31114,9896, -31238,9512, -31357,9127, -31471,8740, -31581,8351, -31686,7962, -31786,7571, -31881,7180, -31972,6787, -32058,6393, -32138,5998, -32214,5602, -32286,5205, -32352,4808, -32413,4410, -32470,4011, -32522,3612, -32568,3212, -32610,2811, -32647,2411, -32679,2009, -32706,1608, -32729,1206, -32746,804, -32758,402, -32766};
52 53 54

#define SCALE 0x3FFF

gauthier's avatar
gauthier committed
55
int32_t lte_ul_channel_estimation(PHY_VARS_eNB *phy_vars_eNB,
56 57 58 59 60 61 62
                                  uint8_t eNB_id,
                                  uint8_t UE_id,
                                  uint8_t sched_subframe,
                                  unsigned char l,
                                  unsigned char Ns,
                                  uint8_t cooperation_flag)
{
63 64 65

  LTE_DL_FRAME_PARMS *frame_parms = &phy_vars_eNB->lte_frame_parms;
  LTE_eNB_PUSCH *eNB_pusch_vars = phy_vars_eNB->lte_eNB_pusch_vars[UE_id];
gauthier's avatar
gauthier committed
66 67 68 69 70
  int32_t **ul_ch_estimates=eNB_pusch_vars->drs_ch_estimates[eNB_id];
  int32_t **ul_ch_estimates_time=  eNB_pusch_vars->drs_ch_estimates_time[eNB_id];
  int32_t **ul_ch_estimates_0=  eNB_pusch_vars->drs_ch_estimates_0[eNB_id];
  int32_t **ul_ch_estimates_1=  eNB_pusch_vars->drs_ch_estimates_1[eNB_id];
  int32_t **rxdataF_ext=  eNB_pusch_vars->rxdataF_ext[eNB_id];
knopp's avatar
 
knopp committed
71 72
  int subframe = phy_vars_eNB->proc[sched_subframe].subframe_rx;
  uint8_t harq_pid = subframe2harq_pid(frame_parms,phy_vars_eNB->proc[sched_subframe].frame_rx,subframe);
gauthier's avatar
gauthier committed
73 74 75 76 77 78 79
  int16_t delta_phase = 0;
  int16_t *ru1 = ru_90;
  int16_t *ru2 = ru_90;
  int16_t current_phase1,current_phase2;
  uint16_t N_rb_alloc = phy_vars_eNB->ulsch_eNB[UE_id]->harq_processes[harq_pid]->nb_rb;
  uint16_t aa,Msc_RS,Msc_RS_idx;
  uint16_t * Msc_idx_ptr;
80
  int k,pilot_pos1 = 3 - frame_parms->Ncp, pilot_pos2 = 10 - 2*frame_parms->Ncp;
gauthier's avatar
gauthier committed
81 82 83 84 85
  int16_t alpha, beta;
  int32_t *ul_ch1=NULL, *ul_ch2=NULL;
  int32_t *ul_ch1_0=NULL,*ul_ch2_0=NULL,*ul_ch1_1=NULL,*ul_ch2_1=NULL;
  int16_t ul_ch_estimates_re,ul_ch_estimates_im;
  int32_t rx_power_correction;
86

Xiwen JIANG's avatar
Xiwen JIANG committed
87
  //uint8_t nb_antennas_rx = frame_parms->nb_antenna_ports_eNB;
gauthier's avatar
gauthier committed
88
  uint8_t nb_antennas_rx = frame_parms->nb_antennas_rx;
89
  uint8_t cyclic_shift;
90

gauthier's avatar
gauthier committed
91 92 93 94
  uint32_t alpha_ind;
  uint32_t u=frame_parms->pusch_config_common.ul_ReferenceSignalsPUSCH.grouphop[Ns+(subframe<<1)];
  uint32_t v=frame_parms->pusch_config_common.ul_ReferenceSignalsPUSCH.seqhop[Ns+(subframe<<1)];
  int32_t tmp_estimates[N_rb_alloc*12] __attribute__((aligned(16)));
95 96 97 98 99 100

  int symbol_offset,i,j;

  //debug_msg("lte_ul_channel_estimation: cyclic shift %d\n",cyclicShift);


gauthier's avatar
gauthier committed
101 102
  int16_t alpha_re[12] = {32767, 28377, 16383,     0,-16384,  -28378,-32768,-28378,-16384,    -1, 16383, 28377};
  int16_t alpha_im[12] = {0,     16383, 28377, 32767, 28377,   16383,     0,-16384,-28378,-32768,-28378,-16384};
103

gauthier's avatar
gauthier committed
104
  int32_t *in_fft_ptr_0 = (int32_t*)0,*in_fft_ptr_1 = (int32_t*)0,
105 106 107
           *temp_out_fft_0_ptr = (int32_t*)0,*out_fft_ptr_0 = (int32_t*)0,
            *temp_out_fft_1_ptr = (int32_t*)0,*out_fft_ptr_1 = (int32_t*)0,
             *temp_in_ifft_ptr = (int32_t*)0;
108

109
#if defined(__x86_64__) || defined(__i386__)
110 111
  __m128i *rxdataF128,*ul_ref128,*ul_ch128;
  __m128i mmtmpU0,mmtmpU1,mmtmpU2,mmtmpU3;
112 113 114 115
#elif defined(__arm__)
  int16x8_t *rxdataF128,*ul_ref128,*ul_ch128;
  int32x4_t mmtmp0,mmtmp1,mmtmp_re,mmtmp_im;
#endif
116 117 118
  Msc_RS = N_rb_alloc*12;

  cyclic_shift = (frame_parms->pusch_config_common.ul_ReferenceSignalsPUSCH.cyclicShift +
119 120
                  phy_vars_eNB->ulsch_eNB[UE_id]->harq_processes[harq_pid]->n_DMRS2 +
                  frame_parms->pusch_config_common.ul_ReferenceSignalsPUSCH.nPRS[(subframe<<1)+Ns]) % 12;
121

122
#if defined(USER_MODE)
gauthier's avatar
gauthier committed
123
  Msc_idx_ptr = (uint16_t*) bsearch(&Msc_RS, dftsizes, 33, sizeof(uint16_t), compareints);
124

125 126 127 128 129 130
  if (Msc_idx_ptr)
    Msc_RS_idx = Msc_idx_ptr - dftsizes;
  else {
    msg("lte_ul_channel_estimation: index for Msc_RS=%d not found\n",Msc_RS);
    return(-1);
  }
131

132
#else
gauthier's avatar
gauthier committed
133
  uint8_t b;
134 135

  for (b=0; b<33; b++)
136 137
    if (Msc_RS==dftsizes[b])
      Msc_RS_idx = b;
138

139 140
#endif

knopp's avatar
 
knopp committed
141 142
  //  LOG_I(PHY,"subframe %d, Ns %d, l %d, Msc_RS = %d, Msc_RS_idx = %d, u %d, v %d, cyclic_shift %d\n",subframe,Ns,l,Msc_RS, Msc_RS_idx,u,v,cyclic_shift);
#ifdef DEBUG_CH
143 144

#ifdef USER_MODE
145

146 147 148 149
  if (Ns==0)
    write_output("drs_seq0.m","drsseq0",ul_ref_sigs_rx[u][v][Msc_RS_idx],2*Msc_RS,2,1);
  else
    write_output("drs_seq1.m","drsseq1",ul_ref_sigs_rx[u][v][Msc_RS_idx],2*Msc_RS,2,1);
150

151 152 153 154 155 156 157 158 159
#endif
#endif

  rx_power_correction = 1;

  if (l == (3 - frame_parms->Ncp)) {

    symbol_offset = frame_parms->N_RB_UL*12*(l+((7-frame_parms->Ncp)*(Ns&1)));

160
    for (aa=0; aa<nb_antennas_rx; aa++) {
161 162
      //           msg("Componentwise prod aa %d, symbol_offset %d,ul_ch_estimates %p,ul_ch_estimates[aa] %p,ul_ref_sigs_rx[0][0][Msc_RS_idx] %p\n",aa,symbol_offset,ul_ch_estimates,ul_ch_estimates[aa],ul_ref_sigs_rx[0][0][Msc_RS_idx]);

163
#if defined(__x86_64__) || defined(__i386__)
164 165 166
      rxdataF128 = (__m128i *)&rxdataF_ext[aa][symbol_offset];
      ul_ch128   = (__m128i *)&ul_ch_estimates[aa][symbol_offset];
      ul_ref128  = (__m128i *)ul_ref_sigs_rx[u][v][Msc_RS_idx];
167 168 169 170 171
#elif defined(__arm__)
      rxdataF128 = (int16x8_t *)&rxdataF_ext[aa][symbol_offset];
      ul_ch128   = (int16x8_t *)&ul_ch_estimates[aa][symbol_offset];
      ul_ref128  = (int16x8_t *)ul_ref_sigs_rx[u][v][Msc_RS_idx];
#endif
172

173
      for (i=0; i<Msc_RS/12; i++) {
174
#if defined(__x86_64__) || defined(__i386__)
175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217
        // multiply by conjugated channel
        mmtmpU0 = _mm_madd_epi16(ul_ref128[0],rxdataF128[0]);
        // mmtmpU0 contains real part of 4 consecutive outputs (32-bit)
        mmtmpU1 = _mm_shufflelo_epi16(ul_ref128[0],_MM_SHUFFLE(2,3,0,1));
        mmtmpU1 = _mm_shufflehi_epi16(mmtmpU1,_MM_SHUFFLE(2,3,0,1));
        mmtmpU1 = _mm_sign_epi16(mmtmpU1,*(__m128i*)&conjugate[0]);
        mmtmpU1 = _mm_madd_epi16(mmtmpU1,rxdataF128[0]);
        // mmtmpU1 contains imag part of 4 consecutive outputs (32-bit)
        mmtmpU0 = _mm_srai_epi32(mmtmpU0,15);
        mmtmpU1 = _mm_srai_epi32(mmtmpU1,15);
        mmtmpU2 = _mm_unpacklo_epi32(mmtmpU0,mmtmpU1);
        mmtmpU3 = _mm_unpackhi_epi32(mmtmpU0,mmtmpU1);

        ul_ch128[0] = _mm_packs_epi32(mmtmpU2,mmtmpU3);
        //  printf("rb %d ch: %d %d\n",i,((int16_t*)ul_ch128)[0],((int16_t*)ul_ch128)[1]);
        // multiply by conjugated channel
        mmtmpU0 = _mm_madd_epi16(ul_ref128[1],rxdataF128[1]);
        // mmtmpU0 contains real part of 4 consecutive outputs (32-bit)
        mmtmpU1 = _mm_shufflelo_epi16(ul_ref128[1],_MM_SHUFFLE(2,3,0,1));
        mmtmpU1 = _mm_shufflehi_epi16(mmtmpU1,_MM_SHUFFLE(2,3,0,1));
        mmtmpU1 = _mm_sign_epi16(mmtmpU1,*(__m128i*)conjugate);
        mmtmpU1 = _mm_madd_epi16(mmtmpU1,rxdataF128[1]);
        // mmtmpU1 contains imag part of 4 consecutive outputs (32-bit)
        mmtmpU0 = _mm_srai_epi32(mmtmpU0,15);
        mmtmpU1 = _mm_srai_epi32(mmtmpU1,15);
        mmtmpU2 = _mm_unpacklo_epi32(mmtmpU0,mmtmpU1);
        mmtmpU3 = _mm_unpackhi_epi32(mmtmpU0,mmtmpU1);

        ul_ch128[1] = _mm_packs_epi32(mmtmpU2,mmtmpU3);

        mmtmpU0 = _mm_madd_epi16(ul_ref128[2],rxdataF128[2]);
        // mmtmpU0 contains real part of 4 consecutive outputs (32-bit)
        mmtmpU1 = _mm_shufflelo_epi16(ul_ref128[2],_MM_SHUFFLE(2,3,0,1));
        mmtmpU1 = _mm_shufflehi_epi16(mmtmpU1,_MM_SHUFFLE(2,3,0,1));
        mmtmpU1 = _mm_sign_epi16(mmtmpU1,*(__m128i*)conjugate);
        mmtmpU1 = _mm_madd_epi16(mmtmpU1,rxdataF128[2]);
        // mmtmpU1 contains imag part of 4 consecutive outputs (32-bit)
        mmtmpU0 = _mm_srai_epi32(mmtmpU0,15);
        mmtmpU1 = _mm_srai_epi32(mmtmpU1,15);
        mmtmpU2 = _mm_unpacklo_epi32(mmtmpU0,mmtmpU1);
        mmtmpU3 = _mm_unpackhi_epi32(mmtmpU0,mmtmpU1);

        ul_ch128[2] = _mm_packs_epi32(mmtmpU2,mmtmpU3);
218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259
#elif defined(__arm__)
      mmtmp0 = vmull_s16(((int16x4_t*)ul_ref128)[0],((int16x4_t*)rxdataF128)[0]);
      mmtmp1 = vmull_s16(((int16x4_t*)ul_ref128)[1],((int16x4_t*)rxdataF128)[1]);
      mmtmp_re = vcombine_s32(vpadd_s32(vget_low_s32(mmtmp0),vget_high_s32(mmtmp0)),
                              vpadd_s32(vget_low_s32(mmtmp1),vget_high_s32(mmtmp1)));
      mmtmp0 = vmull_s16(vrev32_s16(vmul_s16(((int16x4_t*)ul_ref128)[0],*(int16x4_t*)conjugate)), ((int16x4_t*)rxdataF128)[0]);
      mmtmp1 = vmull_s16(vrev32_s16(vmul_s16(((int16x4_t*)ul_ref128)[1],*(int16x4_t*)conjugate)), ((int16x4_t*)rxdataF128)[1]);
      mmtmp_im = vcombine_s32(vpadd_s32(vget_low_s32(mmtmp0),vget_high_s32(mmtmp0)),
                              vpadd_s32(vget_low_s32(mmtmp1),vget_high_s32(mmtmp1)));

      ul_ch128[0] = vcombine_s16(vmovn_s32(mmtmp_re),vmovn_s32(mmtmp_im));
      ul_ch128++;
      ul_ref128++;
      rxdataF128++;
      mmtmp0 = vmull_s16(((int16x4_t*)ul_ref128)[0],((int16x4_t*)rxdataF128)[0]);
      mmtmp1 = vmull_s16(((int16x4_t*)ul_ref128)[1],((int16x4_t*)rxdataF128)[1]);
      mmtmp_re = vcombine_s32(vpadd_s32(vget_low_s32(mmtmp0),vget_high_s32(mmtmp0)),
                              vpadd_s32(vget_low_s32(mmtmp1),vget_high_s32(mmtmp1)));
      mmtmp0 = vmull_s16(vrev32_s16(vmul_s16(((int16x4_t*)ul_ref128)[0],*(int16x4_t*)conjugate)), ((int16x4_t*)rxdataF128)[0]);
      mmtmp1 = vmull_s16(vrev32_s16(vmul_s16(((int16x4_t*)ul_ref128)[1],*(int16x4_t*)conjugate)), ((int16x4_t*)rxdataF128)[1]);
      mmtmp_im = vcombine_s32(vpadd_s32(vget_low_s32(mmtmp0),vget_high_s32(mmtmp0)),
                              vpadd_s32(vget_low_s32(mmtmp1),vget_high_s32(mmtmp1)));

      ul_ch128[0] = vcombine_s16(vmovn_s32(mmtmp_re),vmovn_s32(mmtmp_im));
      ul_ch128++;
      ul_ref128++;
      rxdataF128++;

      mmtmp0 = vmull_s16(((int16x4_t*)ul_ref128)[0],((int16x4_t*)rxdataF128)[0]);
      mmtmp1 = vmull_s16(((int16x4_t*)ul_ref128)[1],((int16x4_t*)rxdataF128)[1]);
      mmtmp_re = vcombine_s32(vpadd_s32(vget_low_s32(mmtmp0),vget_high_s32(mmtmp0)),
                              vpadd_s32(vget_low_s32(mmtmp1),vget_high_s32(mmtmp1)));
      mmtmp0 = vmull_s16(vrev32_s16(vmul_s16(((int16x4_t*)ul_ref128)[0],*(int16x4_t*)conjugate)), ((int16x4_t*)rxdataF128)[0]);
      mmtmp1 = vmull_s16(vrev32_s16(vmul_s16(((int16x4_t*)ul_ref128)[1],*(int16x4_t*)conjugate)), ((int16x4_t*)rxdataF128)[1]);
      mmtmp_im = vcombine_s32(vpadd_s32(vget_low_s32(mmtmp0),vget_high_s32(mmtmp0)),
                              vpadd_s32(vget_low_s32(mmtmp1),vget_high_s32(mmtmp1)));

      ul_ch128[0] = vcombine_s16(vmovn_s32(mmtmp_re),vmovn_s32(mmtmp_im));
      ul_ch128++;
      ul_ref128++;
      rxdataF128++;

260

261
#endif
262 263 264
        ul_ch128+=3;
        ul_ref128+=3;
        rxdataF128+=3;
265 266 267
      }

      alpha_ind = 0;
268 269 270 271 272

      if((cyclic_shift != 0)) {
        // Compensating for the phase shift introduced at the transmitte
#ifdef DEBUG_CH
        write_output("drs_est_pre.m","drsest_pre",ul_ch_estimates[0],300*12,1,1);
273
#endif
274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293

        for(i=symbol_offset; i<symbol_offset+Msc_RS; i++) {
          ul_ch_estimates_re = ((int16_t*) ul_ch_estimates[aa])[i<<1];
          ul_ch_estimates_im = ((int16_t*) ul_ch_estimates[aa])[(i<<1)+1];
          //    ((int16_t*) ul_ch_estimates[aa])[i<<1] =  (i%2 == 1? 1:-1) * ul_ch_estimates_re;
          ((int16_t*) ul_ch_estimates[aa])[i<<1] =
            (int16_t) (((int32_t) (alpha_re[alpha_ind]) * (int32_t) (ul_ch_estimates_re) +
                        (int32_t) (alpha_im[alpha_ind]) * (int32_t) (ul_ch_estimates_im))>>15);

          //((int16_t*) ul_ch_estimates[aa])[(i<<1)+1] =  (i%2 == 1? 1:-1) * ul_ch_estimates_im;
          ((int16_t*) ul_ch_estimates[aa])[(i<<1)+1] =
            (int16_t) (((int32_t) (alpha_re[alpha_ind]) * (int32_t) (ul_ch_estimates_im) -
                        (int32_t) (alpha_im[alpha_ind]) * (int32_t) (ul_ch_estimates_re))>>15);

          alpha_ind+=cyclic_shift;

          if (alpha_ind>11)
            alpha_ind-=12;
        }

294
#ifdef DEBUG_CH
295
        write_output("drs_est_post.m","drsest_post",ul_ch_estimates[0],300*12,1,1);
296
#endif
297 298 299
      }

      //copy MIMO channel estimates to temporary buffer for EMOS
gauthier's avatar
gauthier committed
300
      //memcpy(&ul_ch_estimates_0[aa][symbol_offset],&ul_ch_estimates[aa][symbol_offset],frame_parms->ofdm_symbol_size*sizeof(int32_t)*2);
301

302
      memset(temp_in_ifft_0,0,frame_parms->ofdm_symbol_size*sizeof(int32_t));
303

304
      // Convert to time domain for visualization
305 306
      for(i=0; i<Msc_RS; i++)
        ((int32_t*)temp_in_ifft_0)[i] = ul_ch_estimates[aa][symbol_offset+i];
307 308 309
      switch(frame_parms->N_RB_DL) {
      case 6:
	
310
	idft128((int16_t*) temp_in_ifft_0,
311 312 313 314 315
	       (int16_t*) ul_ch_estimates_time[aa],
	       1);
	break;
      case 25:
	
316
	idft512((int16_t*) temp_in_ifft_0,
317 318 319 320 321
	       (int16_t*) ul_ch_estimates_time[aa],
	       1);
	break;
      case 50:
	
322
	idft1024((int16_t*) temp_in_ifft_0,
323 324 325 326 327
	       (int16_t*) ul_ch_estimates_time[aa],
	       1);
	break;
      case 100:
	
328
	idft2048((int16_t*) temp_in_ifft_0,
329 330 331
	       (int16_t*) ul_ch_estimates_time[aa],
	       1);
	break;
332 333
      }

334 335
#ifdef DEBUG_CH

336
      if (aa==0) {
337 338 339
        if (Ns == 0) {
          write_output("rxdataF_ext.m","rxF_ext",&rxdataF_ext[aa][symbol_offset],512*2,2,1);
          write_output("tmpin_ifft.m","drs_in",temp_in_ifft_0,512,1,1);
340
          write_output("drs_est0.m","drs0",ul_ch_estimates_time[aa],512,1,1);
341
        } else
342
          write_output("drs_est1.m","drs1",ul_ch_estimates_time[aa],512,1,1);
343
      }
344

345 346 347 348
#endif


      if(cooperation_flag == 2) {
349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395
        memset(temp_in_ifft_0,0,frame_parms->ofdm_symbol_size*sizeof(int32_t*)*2);
        memset(temp_in_ifft_1,0,frame_parms->ofdm_symbol_size*sizeof(int32_t*)*2);
        memset(temp_in_fft_0,0,frame_parms->ofdm_symbol_size*sizeof(int32_t*)*2);
        memset(temp_in_fft_1,0,frame_parms->ofdm_symbol_size*sizeof(int32_t*)*2);

        temp_in_ifft_ptr = &temp_in_ifft_0[0];

        i = symbol_offset;

        for(j=0; j<(frame_parms->N_RB_UL*12); j++) {
          temp_in_ifft_ptr[j] = ul_ch_estimates[aa][i];
          i++;
        }

        alpha_ind = 0;

        // Compensating for the phase shift introduced at the transmitter
        for(i=symbol_offset; i<symbol_offset+Msc_RS; i++) {
          ul_ch_estimates_re = ((int16_t*) ul_ch_estimates[aa])[i<<1];
          ul_ch_estimates_im = ((int16_t*) ul_ch_estimates[aa])[(i<<1)+1];
          //    ((int16_t*) ul_ch_estimates[aa])[i<<1] =  (i%2 == 1? 1:-1) * ul_ch_estimates_re;
          ((int16_t*) ul_ch_estimates[aa])[i<<1] =
            (int16_t) (((int32_t) (alpha_re[alpha_ind]) * (int32_t) (ul_ch_estimates_re) +
                        (int32_t) (alpha_im[alpha_ind]) * (int32_t) (ul_ch_estimates_im))>>15);

          //((int16_t*) ul_ch_estimates[aa])[(i<<1)+1] =  (i%2 == 1? 1:-1) * ul_ch_estimates_im;
          ((int16_t*) ul_ch_estimates[aa])[(i<<1)+1] =
            (int16_t) (((int32_t) (alpha_re[alpha_ind]) * (int32_t) (ul_ch_estimates_im) -
                        (int32_t) (alpha_im[alpha_ind]) * (int32_t) (ul_ch_estimates_re))>>15);

          alpha_ind+=10;

          if (alpha_ind>11)
            alpha_ind-=12;
        }

        //Extracting Channel Estimates for Distributed Alamouti Receiver Combining

        temp_in_ifft_ptr = &temp_in_ifft_1[0];

        i = symbol_offset;

        for(j=0; j<(frame_parms->N_RB_UL*12); j++) {
          temp_in_ifft_ptr[j] = ul_ch_estimates[aa][i];
          i++;
        }

396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429
	switch (frame_parms->N_RB_DL) {
	case 6:
	  idft128((int16_t*) &temp_in_ifft_0[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_0,
		  1);
	  idft128((int16_t*) &temp_in_ifft_1[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_1,
		  1);
	  break;
	case 25:
	  idft512((int16_t*) &temp_in_ifft_0[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_0,
		  1);
	  idft512((int16_t*) &temp_in_ifft_1[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_1,
		  1);
	  break;
	case 50:
	  idft1024((int16_t*) &temp_in_ifft_0[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_0,
		  1);
	  idft1024((int16_t*) &temp_in_ifft_1[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_1,
		  1);
	  break;
	case 100:
	  idft2048((int16_t*) &temp_in_ifft_0[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_0,
		  1);
	  idft2048((int16_t*) &temp_in_ifft_1[0],                          // Performing IFFT on Combined Channel Estimates
		  temp_out_ifft_1,
		  1);
	  break;
	}
430 431 432 433 434 435 436

        // because the ifft is not power preserving, we should apply the factor sqrt(power_correction) here, but we rather apply power_correction here and nothing after the next fft
        in_fft_ptr_0 = &temp_in_fft_0[0];
        in_fft_ptr_1 = &temp_in_fft_1[0];

        for(j=0; j<(1<<(frame_parms->log2_symbol_size))/12; j++) {
          if (j>19) {
437 438 439 440
            ((int16_t*)in_fft_ptr_0)[-40+(2*j)] = ((int16_t*)temp_out_ifft_0)[-80+(2*j)]*rx_power_correction;
            ((int16_t*)in_fft_ptr_0)[-40+(2*j)+1] = ((int16_t*)temp_out_ifft_0)[-80+(2*j+1)]*rx_power_correction;
            ((int16_t*)in_fft_ptr_1)[-40+(2*j)] = ((int16_t*)temp_out_ifft_1)[-80+(2*j)]*rx_power_correction;
            ((int16_t*)in_fft_ptr_1)[-40+(2*j)+1] = ((int16_t*)temp_out_ifft_1)[-80+(2*j)+1]*rx_power_correction;
441
          } else {
442 443 444 445
            ((int16_t*)in_fft_ptr_0)[2*(frame_parms->ofdm_symbol_size-20+j)] = ((int16_t*)temp_out_ifft_0)[2*(frame_parms->ofdm_symbol_size-20+j)]*rx_power_correction;
            ((int16_t*)in_fft_ptr_0)[2*(frame_parms->ofdm_symbol_size-20+j)+1] = ((int16_t*)temp_out_ifft_0)[2*(frame_parms->ofdm_symbol_size-20+j)+1]*rx_power_correction;
            ((int16_t*)in_fft_ptr_1)[2*(frame_parms->ofdm_symbol_size-20+j)] = ((int16_t*)temp_out_ifft_1)[2*(frame_parms->ofdm_symbol_size-20+j)]*rx_power_correction;
            ((int16_t*)in_fft_ptr_1)[2*(frame_parms->ofdm_symbol_size-20+j)+1] = ((int16_t*)temp_out_ifft_1)[2*(frame_parms->ofdm_symbol_size-20+j)+1]*rx_power_correction;
446
          }
447 448
        }

449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474
	switch (frame_parms->N_RB_DL) {
        case 6:
	  dft128((int16_t*) &temp_in_fft_0[0],     
		 // Performing FFT to obtain the Channel Estimates for UE0 to eNB1
		 temp_out_fft_0,
		 1);
	  break;
        case 25:
	  dft512((int16_t*) &temp_in_fft_0[0],     
		 // Performing FFT to obtain the Channel Estimates for UE0 to eNB1
		 temp_out_fft_0,
		 1);
	  break;
        case 50:
	  dft1024((int16_t*) &temp_in_fft_0[0],     
		 // Performing FFT to obtain the Channel Estimates for UE0 to eNB1
		 temp_out_fft_0,
		 1);
	  break;
        case 100:
	  dft2048((int16_t*) &temp_in_fft_0[0],     
		 // Performing FFT to obtain the Channel Estimates for UE0 to eNB1
		 temp_out_fft_0,
		 1);
	  break;
	}
475 476 477 478 479 480 481

        out_fft_ptr_0 = &ul_ch_estimates_0[aa][symbol_offset]; // CHANNEL ESTIMATES FOR UE0 TO eNB1
        temp_out_fft_0_ptr = (int32_t*) temp_out_fft_0;

        i=0;

        for(j=0; j<frame_parms->N_RB_UL*12; j++) {
482
          out_fft_ptr_0[i] = temp_out_fft_0_ptr[j];
483 484
          i++;
        }
485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506
	switch (frame_parms->N_RB_DL) {
	case 6:
	  dft128((int16_t*) &temp_in_fft_1[0],                          // Performing FFT to obtain the Channel Estimates for UE1 to eNB1
		 temp_out_fft_1,
		 1);
	  break;
	case 25:
	  dft512((int16_t*) &temp_in_fft_1[0],                          // Performing FFT to obtain the Channel Estimates for UE1 to eNB1
		 temp_out_fft_1,
		 1);
	  break;
	case 50:
	  dft1024((int16_t*) &temp_in_fft_1[0],                          // Performing FFT to obtain the Channel Estimates for UE1 to eNB1
		 temp_out_fft_1,
		 1);
	  break;
	case 100:
	  dft2048((int16_t*) &temp_in_fft_1[0],                          // Performing FFT to obtain the Channel Estimates for UE1 to eNB1
		 temp_out_fft_1,
		 1);
	  break;
	}
507 508 509 510 511 512 513

        out_fft_ptr_1 = &ul_ch_estimates_1[aa][symbol_offset];   // CHANNEL ESTIMATES FOR UE1 TO eNB1
        temp_out_fft_1_ptr = (int32_t*) temp_out_fft_1;

        i=0;

        for(j=0; j<frame_parms->N_RB_UL*12; j++) {
514
          out_fft_ptr_1[i] = temp_out_fft_1_ptr[j];
515 516
          i++;
        }
517 518 519

#ifdef DEBUG_CH
#ifdef USER_MODE
520 521 522 523 524 525 526 527 528 529

        if((aa == 0)&& (cooperation_flag == 2)) {
          write_output("test1.m","t1",temp_in_ifft_0,512,1,1);
          write_output("test2.m","t2",temp_out_ifft_0,512*2,2,1);
          write_output("test3.m","t3",temp_in_fft_0,512,1,1);
          write_output("test4.m","t4",temp_out_fft_0,512,1,1);
          write_output("test5.m","t5",temp_in_fft_1,512,1,1);
          write_output("test6.m","t6",temp_out_fft_1,512,1,1);
        }

530 531 532 533 534 535 536
#endif
#endif

      }//cooperation_flag == 2

      if (Ns&1) {//we are in the second slot of the sub-frame, so do the interpolation

537 538
        ul_ch1 = &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*pilot_pos1];
        ul_ch2 = &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*pilot_pos2];
539 540


541 542 543
        if(cooperation_flag == 2) { // For Distributed Alamouti
          ul_ch1_0 = &ul_ch_estimates_0[aa][frame_parms->N_RB_UL*12*pilot_pos1];
          ul_ch2_0 = &ul_ch_estimates_0[aa][frame_parms->N_RB_UL*12*pilot_pos2];
544

545 546 547
          ul_ch1_1 = &ul_ch_estimates_1[aa][frame_parms->N_RB_UL*12*pilot_pos1];
          ul_ch2_1 = &ul_ch_estimates_1[aa][frame_parms->N_RB_UL*12*pilot_pos2];
        }
548

549 550 551 552 553 554
        // Estimation of phase difference between the 2 channel estimates
        delta_phase = lte_ul_freq_offset_estimation(frame_parms,
                      ul_ch_estimates[aa],
                      N_rb_alloc);
        // negative phase index indicates negative Im of ru
        //    msg("delta_phase: %d\n",delta_phase);
555 556

#ifdef DEBUG_CH
557
        msg("lte_ul_channel_estimation: ul_ch1 = %p, ul_ch2 = %p, pilot_pos1=%d, pilot_pos2=%d\n",ul_ch1, ul_ch2, pilot_pos1,pilot_pos2);
558 559
#endif

560 561 562 563 564 565 566
        for (k=0; k<frame_parms->symbols_per_tti; k++) {

          // we scale alpha and beta by SCALE (instead of 0x7FFF) to avoid overflows
          alpha = (int16_t) (((int32_t) SCALE * (int32_t) (pilot_pos2-k))/(pilot_pos2-pilot_pos1));
          beta  = (int16_t) (((int32_t) SCALE * (int32_t) (k-pilot_pos1))/(pilot_pos2-pilot_pos1));


567
#ifdef DEBUG_CH
568
          msg("lte_ul_channel_estimation: k=%d, alpha = %d, beta = %d\n",k,alpha,beta);
569
#endif
570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594
          //symbol_offset_subframe = frame_parms->N_RB_UL*12*k;

          // interpolate between estimates
          if ((k != pilot_pos1) && (k != pilot_pos2))  {
            //          multadd_complex_vector_real_scalar((int16_t*) ul_ch1,alpha,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);
            //          multadd_complex_vector_real_scalar((int16_t*) ul_ch2,beta ,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);

            //          multadd_complex_vector_real_scalar((int16_t*) ul_ch1,SCALE,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);
            //          multadd_complex_vector_real_scalar((int16_t*) ul_ch2,SCALE,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);
            //          msg("phase = %d\n",ru[2*cmax(((delta_phase/7)*(k-3)),0)]);

            // the phase is linearly interpolated
            current_phase1 = (delta_phase/7)*(k-pilot_pos1);
            current_phase2 = (delta_phase/7)*(k-pilot_pos2);
            //          msg("sym: %d, current_phase1: %d, current_phase2: %d\n",k,current_phase1,current_phase2);
            // set the right quadrant
            (current_phase1 > 0) ? (ru1 = ru_90) : (ru1 = ru_90c);
            (current_phase2 > 0) ? (ru2 = ru_90) : (ru2 = ru_90c);
            // take absolute value and clip
            current_phase1 = cmin(abs(current_phase1),127);
            current_phase2 = cmin(abs(current_phase2),127);

            //          msg("sym: %d, current_phase1: %d, ru: %d + j%d, current_phase2: %d, ru: %d + j%d\n",k,current_phase1,ru1[2*current_phase1],ru1[2*current_phase1+1],current_phase2,ru2[2*current_phase2],ru2[2*current_phase2+1]);

            // rotate channel estimates by estimated phase
595 596 597 598 599 600 601 602 603 604 605
            rotate_cpx_vector((int16_t*) ul_ch1,
                              &ru1[2*current_phase1],
                              (int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],
                              Msc_RS,
                              15);

            rotate_cpx_vector((int16_t*) ul_ch2,
                              &ru2[2*current_phase2],
                              (int16_t*) &tmp_estimates[0],
                              Msc_RS,
                              15);
606

607 608 609
            // Combine the two rotated estimates
            multadd_complex_vector_real_scalar((int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],SCALE,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);
            multadd_complex_vector_real_scalar((int16_t*) &tmp_estimates[0],SCALE,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);
610

611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638
            /*
            if ((k<pilot_pos1) || ((k>pilot_pos2))) {

                multadd_complex_vector_real_scalar((int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],SCALE>>1,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);

                multadd_complex_vector_real_scalar((int16_t*) &tmp_estimates[0],SCALE>>1,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);

            } else {

                multadd_complex_vector_real_scalar((int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],SCALE>>1,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);

                multadd_complex_vector_real_scalar((int16_t*) &tmp_estimates[0],SCALE>>1,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);

                //              multadd_complex_vector_real_scalar((int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],alpha,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);

                //              multadd_complex_vector_real_scalar((int16_t*) &tmp_estimates[0],beta ,(int16_t*) &ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);

            }
            */

            //      memcpy(&ul_ch_estimates[aa][frame_parms->N_RB_UL*12*k],ul_ch1,Msc_RS*sizeof(int32_t));
            if(cooperation_flag == 2) { // For Distributed Alamouti
              multadd_complex_vector_real_scalar((int16_t*) ul_ch1_0,beta ,(int16_t*) &ul_ch_estimates_0[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);
              multadd_complex_vector_real_scalar((int16_t*) ul_ch2_0,alpha,(int16_t*) &ul_ch_estimates_0[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);

              multadd_complex_vector_real_scalar((int16_t*) ul_ch1_1,beta ,(int16_t*) &ul_ch_estimates_1[aa][frame_parms->N_RB_UL*12*k],1,Msc_RS);
              multadd_complex_vector_real_scalar((int16_t*) ul_ch2_1,alpha,(int16_t*) &ul_ch_estimates_1[aa][frame_parms->N_RB_UL*12*k],0,Msc_RS);
            }
639 640

          }
641 642 643 644 645 646 647 648 649 650 651 652 653 654 655
        } //for(k=...

        // because of the scaling of alpha and beta we also need to scale the final channel estimate at the pilot positions

        //    multadd_complex_vector_real_scalar((int16_t*) ul_ch1,SCALE,(int16_t*) ul_ch1,1,Msc_RS);
        //    multadd_complex_vector_real_scalar((int16_t*) ul_ch2,SCALE,(int16_t*) ul_ch2,1,Msc_RS);

        if(cooperation_flag == 2) { // For Distributed Alamouti
          multadd_complex_vector_real_scalar((int16_t*) ul_ch1_0,SCALE,(int16_t*) ul_ch1_0,1,Msc_RS);
          multadd_complex_vector_real_scalar((int16_t*) ul_ch2_0,SCALE,(int16_t*) ul_ch2_0,1,Msc_RS);

          multadd_complex_vector_real_scalar((int16_t*) ul_ch1_1,SCALE,(int16_t*) ul_ch1_1,1,Msc_RS);
          multadd_complex_vector_real_scalar((int16_t*) ul_ch2_1,SCALE,(int16_t*) ul_ch2_1,1,Msc_RS);
        }

656 657 658 659

      } //if (Ns&1)

    } //for(aa=...
660

661 662 663
  } //if(l==...


664

665
  return(0);
666
}
667

gauthier's avatar
gauthier committed
668
extern uint16_t transmission_offset_tdd[16];
669 670
#define DEBUG_SRS

gauthier's avatar
gauthier committed
671
int32_t lte_srs_channel_estimation(LTE_DL_FRAME_PARMS *frame_parms,
672 673 674 675 676 677
                                   LTE_eNB_COMMON *eNb_common_vars,
                                   LTE_eNB_SRS *eNb_srs_vars,
                                   SOUNDINGRS_UL_CONFIG_DEDICATED *soundingrs_ul_config_dedicated,
                                   unsigned char sub_frame_number,
                                   unsigned char eNb_id)
{
678 679 680

  int T_SFC,aa;
  int N_symb,symbol;
Xiwen JIANG's avatar
Xiwen JIANG committed
681
  uint8_t nb_antennas_rx = frame_parms->nb_antenna_ports_eNB;
682 683 684 685
#ifdef DEBUG_SRS
  char fname[40], vname[40];
#endif

gauthier's avatar
gauthier committed
686
  uint8_t Ssrs  = frame_parms->soundingrs_ul_config_common.srs_SubframeConfig;
687 688 689 690 691

  N_symb = 2*7-frame_parms->Ncp;
  symbol = (sub_frame_number+1)*N_symb-1; //SRS is always in last symbol of subframe
  T_SFC = (Ssrs<=7 ? 5 : 10);

692
  /*
693 694 695 696 697 698 699 700 701 702
     msg("SRS channel estimation eNb %d, subframs %d, %d %d %d %d %d\n",eNb_id,sub_frame_number,
     SRS_parms->Csrs,
     SRS_parms->Bsrs,
     SRS_parms->kTC,
     SRS_parms->n_RRC,
     SRS_parms->Ssrs);
  */

  if ((1<<(sub_frame_number%T_SFC))&transmission_offset_tdd[Ssrs]) {

703 704 705
    if (generate_srs_rx(frame_parms,
                        soundingrs_ul_config_dedicated,
                        eNb_srs_vars->srs)==-1) {
706 707 708 709
      msg("lte_srs_channel_estimation: Error in generate_srs_rx\n");
      return(-1);
    }

710
    for (aa=0; aa<nb_antennas_rx; aa++) {
711 712
#ifdef DEBUG_SRS
      msg("SRS channel estimation eNb %d, subframs %d, aarx %d, %p, %p, %p\n",eNb_id,sub_frame_number,aa,
713 714 715
          &eNb_common_vars->rxdataF[eNb_id][aa][2*frame_parms->ofdm_symbol_size*symbol],
          eNb_srs_vars->srs,
          eNb_srs_vars->srs_ch_estimates[eNb_id][aa]);
716 717 718 719 720
#endif

      //write_output("eNb_rxF.m","rxF",&eNb_common_vars->rxdataF[0][aa][2*frame_parms->ofdm_symbol_size*symbol],2*(frame_parms->ofdm_symbol_size),2,1);
      //write_output("eNb_srs.m","srs_eNb",eNb_common_vars->srs,(frame_parms->ofdm_symbol_size),1,1);

721 722 723 724 725
      mult_cpx_conj_vector((int16_t*) &eNb_common_vars->rxdataF[eNb_id][aa][2*frame_parms->ofdm_symbol_size*symbol],
                      (int16_t*) eNb_srs_vars->srs,
                      (int16_t*) eNb_srs_vars->srs_ch_estimates[eNb_id][aa],
                      frame_parms->ofdm_symbol_size,
                      15);
726 727 728 729 730 731 732 733 734 735 736

      //msg("SRS channel estimation cmult out\n");
#ifdef USER_MODE
#ifdef DEBUG_SRS
      sprintf(fname,"eNB_id%d_an%d_srs_ch_est.m",eNb_id,aa);
      sprintf(vname,"eNB%d_%d_srs_ch_est",eNb_id,aa);
      write_output(fname,vname,eNb_srs_vars->srs_ch_estimates[eNb_id][aa],frame_parms->ofdm_symbol_size,1,1);
#endif
#endif
    }
  }
737

738 739
  /*
    else {
740
    for (aa=0;aa<nb_antennas_rx;aa++)
741 742 743 744 745 746
    bzero(eNb_srs_vars->srs_ch_estimates[eNb_id][aa],frame_parms->ofdm_symbol_size*sizeof(int));
    }
  */
  return(0);
}

gauthier's avatar
gauthier committed
747
int16_t lte_ul_freq_offset_estimation(LTE_DL_FRAME_PARMS *frame_parms,
748 749 750 751
                                      int32_t *ul_ch_estimates,
                                      uint16_t nb_rb)
{

752
#if defined(__x86_64__) || defined(__i386__)
753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887
  int k, rb;
  int a_idx = 64;
  uint8_t conj_flag = 0;
  uint8_t output_shift;
  int pilot_pos1 = 3 - frame_parms->Ncp;
  int pilot_pos2 = 10 - 2*frame_parms->Ncp;
  __m128i *ul_ch1 = (__m128i*)&ul_ch_estimates[pilot_pos1*frame_parms->N_RB_UL*12];
  __m128i *ul_ch2 = (__m128i*)&ul_ch_estimates[pilot_pos2*frame_parms->N_RB_UL*12];
  int32_t avg[2];
  int16_t Ravg[2];
  Ravg[0]=0;
  Ravg[1]=0;
  int16_t iv, rv, phase_idx;
  __m128i avg128U1, avg128U2, R[3], mmtmpD0,mmtmpD1,mmtmpD2,mmtmpD3;

  // round(tan((pi/4)*[1:1:N]/N)*pow2(15))
  int16_t alpha[128] = {201, 402, 603, 804, 1006, 1207, 1408, 1610, 1811, 2013, 2215, 2417, 2619, 2822, 3024, 3227, 3431, 3634, 3838, 4042, 4246, 4450, 4655, 4861, 5066, 5272, 5479, 5686, 5893, 6101, 6309, 6518, 6727, 6937, 7147, 7358, 7570, 7782, 7995, 8208, 8422, 8637, 8852, 9068, 9285, 9503, 9721, 9940, 10160, 10381, 10603, 10825, 11049, 11273, 11498, 11725, 11952, 12180, 12410, 12640, 12872, 13104, 13338, 13573, 13809, 14046, 14285, 14525, 14766, 15009, 15253, 15498, 15745, 15993, 16243, 16494, 16747, 17001, 17257, 17515, 17774, 18035, 18298, 18563, 18829, 19098, 19368, 19640, 19915, 20191, 20470, 20750, 21033, 21318, 21605, 21895, 22187, 22481, 22778, 23078, 23380, 23685, 23992, 24302, 24615, 24931, 25250, 25572, 25897, 26226, 26557, 26892, 27230, 27572, 27917, 28266, 28618, 28975, 29335, 29699, 30067, 30440, 30817, 31198, 31583, 31973, 32368, 32767};

  // compute log2_maxh (output_shift)
  avg128U1 = _mm_setzero_si128();
  avg128U2 = _mm_setzero_si128();

  for (rb=0; rb<nb_rb; rb++) {
    avg128U1 = _mm_add_epi32(avg128U1,_mm_madd_epi16(ul_ch1[0],ul_ch1[0]));
    avg128U1 = _mm_add_epi32(avg128U1,_mm_madd_epi16(ul_ch1[1],ul_ch1[1]));
    avg128U1 = _mm_add_epi32(avg128U1,_mm_madd_epi16(ul_ch1[2],ul_ch1[2]));

    avg128U2 = _mm_add_epi32(avg128U2,_mm_madd_epi16(ul_ch2[0],ul_ch2[0]));
    avg128U2 = _mm_add_epi32(avg128U2,_mm_madd_epi16(ul_ch2[1],ul_ch2[1]));
    avg128U2 = _mm_add_epi32(avg128U2,_mm_madd_epi16(ul_ch2[2],ul_ch2[2]));

    ul_ch1+=3;
    ul_ch2+=3;
  }

  avg[0] = (((int*)&avg128U1)[0] +
            ((int*)&avg128U1)[1] +
            ((int*)&avg128U1)[2] +
            ((int*)&avg128U1)[3])/(nb_rb*12);

  avg[1] = (((int*)&avg128U2)[0] +
            ((int*)&avg128U2)[1] +
            ((int*)&avg128U2)[2] +
            ((int*)&avg128U2)[3])/(nb_rb*12);

  //    msg("avg0 = %d, avg1 = %d\n",avg[0],avg[1]);
  avg[0] = cmax(avg[0],avg[1]);
  avg[1] = log2_approx(avg[0]);
  output_shift = cmax(0,avg[1]-10);
  //output_shift  = (log2_approx(avg[0])/2)+ log2_approx(frame_parms->nb_antennas_rx-1)+1;
  //    msg("avg= %d, shift = %d\n",avg[0],output_shift);

  ul_ch1 = (__m128i*)&ul_ch_estimates[pilot_pos1*frame_parms->N_RB_UL*12];
  ul_ch2 = (__m128i*)&ul_ch_estimates[pilot_pos2*frame_parms->N_RB_UL*12];

  // correlate and average the 2 channel estimates ul_ch1*ul_ch2
  for (rb=0; rb<nb_rb; rb++) {
    mmtmpD0 = _mm_madd_epi16(ul_ch1[0],ul_ch2[0]);
    mmtmpD1 = _mm_shufflelo_epi16(ul_ch1[0],_MM_SHUFFLE(2,3,0,1));
    mmtmpD1 = _mm_shufflehi_epi16(mmtmpD1,_MM_SHUFFLE(2,3,0,1));
    mmtmpD1 = _mm_sign_epi16(mmtmpD1,*(__m128i*)&conjugate);
    mmtmpD1 = _mm_madd_epi16(mmtmpD1,ul_ch2[0]);
    mmtmpD0 = _mm_srai_epi32(mmtmpD0,output_shift);
    mmtmpD1 = _mm_srai_epi32(mmtmpD1,output_shift);
    mmtmpD2 = _mm_unpacklo_epi32(mmtmpD0,mmtmpD1);
    mmtmpD3 = _mm_unpackhi_epi32(mmtmpD0,mmtmpD1);
    R[0] = _mm_packs_epi32(mmtmpD2,mmtmpD3);

    mmtmpD0 = _mm_madd_epi16(ul_ch1[1],ul_ch2[1]);
    mmtmpD1 = _mm_shufflelo_epi16(ul_ch1[1],_MM_SHUFFLE(2,3,0,1));
    mmtmpD1 = _mm_shufflehi_epi16(mmtmpD1,_MM_SHUFFLE(2,3,0,1));
    mmtmpD1 = _mm_sign_epi16(mmtmpD1,*(__m128i*)&conjugate);
    mmtmpD1 = _mm_madd_epi16(mmtmpD1,ul_ch2[1]);
    mmtmpD0 = _mm_srai_epi32(mmtmpD0,output_shift);
    mmtmpD1 = _mm_srai_epi32(mmtmpD1,output_shift);
    mmtmpD2 = _mm_unpacklo_epi32(mmtmpD0,mmtmpD1);
    mmtmpD3 = _mm_unpackhi_epi32(mmtmpD0,mmtmpD1);
    R[1] = _mm_packs_epi32(mmtmpD2,mmtmpD3);

    mmtmpD0 = _mm_madd_epi16(ul_ch1[2],ul_ch2[2]);
    mmtmpD1 = _mm_shufflelo_epi16(ul_ch1[2],_MM_SHUFFLE(2,3,0,1));
    mmtmpD1 = _mm_shufflehi_epi16(mmtmpD1,_MM_SHUFFLE(2,3,0,1));
    mmtmpD1 = _mm_sign_epi16(mmtmpD1,*(__m128i*)&conjugate);
    mmtmpD1 = _mm_madd_epi16(mmtmpD1,ul_ch2[2]);
    mmtmpD0 = _mm_srai_epi32(mmtmpD0,output_shift);
    mmtmpD1 = _mm_srai_epi32(mmtmpD1,output_shift);
    mmtmpD2 = _mm_unpacklo_epi32(mmtmpD0,mmtmpD1);
    mmtmpD3 = _mm_unpackhi_epi32(mmtmpD0,mmtmpD1);
    R[2] = _mm_packs_epi32(mmtmpD2,mmtmpD3);

    R[0] = _mm_add_epi16(_mm_srai_epi16(R[0],1),_mm_srai_epi16(R[1],1));
    R[0] = _mm_add_epi16(_mm_srai_epi16(R[0],1),_mm_srai_epi16(R[2],1));

    Ravg[0] += (((short*)&R)[0] +
                ((short*)&R)[2] +
                ((short*)&R)[4] +
                ((short*)&R)[6])/(nb_rb*4);

    Ravg[1] += (((short*)&R)[1] +
                ((short*)&R)[3] +
                ((short*)&R)[5] +
                ((short*)&R)[7])/(nb_rb*4);

    ul_ch1+=3;
    ul_ch2+=3;
  }

  // phase estimation on Ravg
  //   Ravg[0] = 56;
  //   Ravg[1] = 0;
  rv = Ravg[0];
  iv = Ravg[1];

  if (iv<0)
    iv = -Ravg[1];

  if (rv<iv) {
    rv = iv;
    iv = Ravg[0];
    conj_flag = 1;
  }

  //   msg("rv = %d, iv = %d\n",rv,iv);
  //   msg("max_avg = %d, log2_approx = %d, shift = %d\n",avg[0], avg[1], output_shift);

  for (k=0; k<6; k++) {
    (iv<(((int32_t)(alpha[a_idx]*rv))>>15)) ? (a_idx -= 32>>k) : (a_idx += 32>>k);
  }

  (conj_flag==1) ? (phase_idx = 127-(a_idx>>1)) : (phase_idx = (a_idx>>1));

  if (Ravg[1]<0)
    phase_idx = -phase_idx;

  return(phase_idx);
888 889 890
#elif defined(__arm__)
  return(0);
#endif
891
}