diff --git a/openair1/PHY/LTE_TRANSPORT/prach.c b/openair1/PHY/LTE_TRANSPORT/prach.c
index e220549045..90c9d63925 100644
--- a/openair1/PHY/LTE_TRANSPORT/prach.c
+++ b/openair1/PHY/LTE_TRANSPORT/prach.c
@@ -69,8 +69,7 @@ void rx_prach0(PHY_VARS_eNB *eNB,
   uint32_t preamble_shift2;
   uint16_t preamble_index0=0,n_shift_ra=0,n_shift_ra_bar;
   uint16_t d_start=0;
-  uint16_t numshift=0;
-  uint16_t *prach_root_sequence_map;
+  uint16_t numshift = 0;
   uint8_t not_found;
   int k=0;
   uint16_t u;
@@ -221,7 +220,7 @@ void rx_prach0(PHY_VARS_eNB *eNB,
 
   if (eNB) start_meas(&eNB->rx_prach);
 
-  prach_root_sequence_map = (prach_fmt < 4) ? prach_root_sequence_map0_3 : prach_root_sequence_map4;
+  const uint16_t *prach_root_sequence_map = (prach_fmt < 4) ? prach_root_sequence_map0_3 : prach_root_sequence_map4;
   // PDP is oversampled, e.g. 1024 sample instead of 839
   // Adapt the NCS (zero-correlation zones) with oversampling factor e.g. 1024/839
   NCS2 = (N_ZC==839) ? ((NCS<<10)/839) : ((NCS<<8)/139);
@@ -495,7 +494,7 @@ void rx_prach0(PHY_VARS_eNB *eNB,
       new_dft = 0;
       
       if (br_flag == 1) {
-        Xu=(c16_t *)eNB->X_u_br[ce_level][preamble_offset-first_nonzero_root_idx];
+        Xu = eNB->X_u_br[ce_level][preamble_offset - first_nonzero_root_idx];
         prach_ifft = prach_ifftp[prach_ifft_cnt++];
         
         if (eNB->prach_vars_br.repetition_number[ce_level]==1) memset(prach_ifft,0,((N_ZC==839)?2048:256)*sizeof(int32_t));
diff --git a/openair1/PHY/LTE_TRANSPORT/prach_common.c b/openair1/PHY/LTE_TRANSPORT/prach_common.c
index 2d9ef9d712..0939398c60 100644
--- a/openair1/PHY/LTE_TRANSPORT/prach_common.c
+++ b/openair1/PHY/LTE_TRANSPORT/prach_common.c
@@ -35,12 +35,13 @@
 #include "PHY/phy_extern_ue.h"
 #include "common/utils/LOG/vcd_signal_dumper.h"
 #include "common/utils/lte/prach_utils.h"
+#include "openair1/PHY/LTE_TRANSPORT/prach_extern.h"
 
 const uint16_t NCS_unrestricted[16] = {0, 13, 15, 18, 22, 26, 32, 38, 46, 59, 76, 93, 119, 167, 279, 419};
 const uint16_t NCS_restricted[15] = {15, 18, 22, 26, 32, 38, 46, 55, 68, 82, 100, 128, 158, 202, 237}; // high-speed case
 const uint16_t NCS_4[7] = {2, 4, 6, 8, 10, 12, 15};
 
-int16_t ru[2*839]; // quantized roots of unity
+c16_t root_unit[839]; // quantized roots of unity
 static uint32_t ZC_inv[839]; // multiplicative inverse for roots u
 uint16_t du[838];
 
@@ -367,13 +368,13 @@ int is_prach_subframe(LTE_DL_FRAME_PARMS *frame_parms, uint32_t frame, uint8_t s
   return(prach_mask);
 }
 
-
 void compute_prach_seq(uint16_t rootSequenceIndex,
                        uint8_t prach_ConfigIndex,
                        uint8_t zeroCorrelationZoneConfig,
                        uint8_t highSpeedFlag,
                        frame_type_t frame_type,
-                       uint32_t X_u[64][839]) {
+                       c16_t X_u[64][839])
+{
   // Compute DFT of x_u => X_u[k] = x_u(inv(u)*k)^* X_u[k] = exp(j\pi u*inv(u)*k*(inv(u)*k+1)/N_ZC)
   unsigned int k,inv_u,i,NCS=0,num_preambles;
   int N_ZC;
@@ -495,7 +496,7 @@ void compute_prach_seq(uint16_t rootSequenceIndex,
 
     for (k=0; k<N_ZC; k++) {
       // 420 is the multiplicative inverse of 2 (required since ru is exp[j 2\pi n])
-      X_u[i][k] = ((uint32_t *)ru)[(((k*(1+(inv_u*k)))%N_ZC)*420)%N_ZC];
+      X_u[i][k] = root_unit[(((k * (1 + (inv_u * k))) % N_ZC) * 420) % N_ZC];
     }
   }
 
@@ -525,8 +526,8 @@ void init_prach_tables(int N_ZC) {
 
   // Compute quantized roots of unity
   for (i=0; i<N_ZC; i++) {
-    ru[i<<1]     = (int16_t)(floor(32767.0*cos(2*M_PI*(double)i/N_ZC)));
-    ru[1+(i<<1)] = (int16_t)(floor(32767.0*sin(2*M_PI*(double)i/N_ZC)));
+    root_unit[i].r = (int16_t)(floor(32767.0 * cos(2 * M_PI * (double)i / N_ZC)));
+    root_unit[i].i = (int16_t)(floor(32767.0 * sin(2 * M_PI * (double)i / N_ZC)));
 #ifdef PRACH_DEBUG
 
     if (i<16)
diff --git a/openair1/PHY/LTE_TRANSPORT/prach_extern.h b/openair1/PHY/LTE_TRANSPORT/prach_extern.h
index 75644e4a5b..c318dac78a 100644
--- a/openair1/PHY/LTE_TRANSPORT/prach_extern.h
+++ b/openair1/PHY/LTE_TRANSPORT/prach_extern.h
@@ -43,22 +43,14 @@
 extern const uint16_t NCS_unrestricted[16];
 extern const uint16_t NCS_restricted[15];
 extern const uint16_t NCS_4[7];
-
-extern int16_t ru[2 * 839]; // quantized roots of unity
+extern c16_t root_unit[839]; // quantized roots of unity
 extern uint16_t du[838];
-
-
-
 // This is table 5.7.1-4 from 36.211
 extern PRACH_TDD_PREAMBLE_MAP tdd_preamble_map[64][7];
 
+extern const uint16_t prach_root_sequence_map0_3[838];
 
-
-
-extern uint16_t prach_root_sequence_map0_3[838];
- 
-
-extern uint16_t prach_root_sequence_map4[138];
+extern const uint16_t prach_root_sequence_map4[138];
 
 void dump_prach_config(LTE_DL_FRAME_PARMS *frame_parms,uint8_t subframe);
 
diff --git a/openair1/PHY/LTE_UE_TRANSPORT/prach_ue.c b/openair1/PHY/LTE_UE_TRANSPORT/prach_ue.c
index 9fe33c189d..4b662e4cf3 100644
--- a/openair1/PHY/LTE_UE_TRANSPORT/prach_ue.c
+++ b/openair1/PHY/LTE_UE_TRANSPORT/prach_ue.c
@@ -63,7 +63,6 @@ int32_t generate_prach( PHY_VARS_UE *ue, uint8_t eNB_id, uint8_t subframe, uint1
   int16_t Ncp;
   uint8_t n_ra_prb;
   uint16_t NCS;
-  uint16_t *prach_root_sequence_map;
   uint16_t preamble_offset,preamble_shift;
   uint16_t preamble_index0,n_shift_ra,n_shift_ra_bar;
   uint16_t d_start=-1,numshift;
@@ -72,11 +71,7 @@ int32_t generate_prach( PHY_VARS_UE *ue, uint8_t eNB_id, uint8_t subframe, uint1
   //uint8_t f_ra,t1_ra;
   uint16_t N_ZC = (prach_fmt<4)?839:139;
   uint8_t not_found;
-  int k;
-  int16_t *Xu;
   uint16_t u;
-  int32_t Xu_re,Xu_im;
-  uint16_t offset,offset2;
   int prach_start;
   int i, prach_len;
   uint16_t first_nonzero_root_idx=0;
@@ -109,7 +104,7 @@ int32_t generate_prach( PHY_VARS_UE *ue, uint8_t eNB_id, uint8_t subframe, uint1
                                   ue->frame_parms.prach_config_common.prach_ConfigInfo.prach_ConfigIndex,
                                   ue->frame_parms.prach_config_common.prach_ConfigInfo.prach_FreqOffset,
                                   tdd_mapindex, Nf);
-  prach_root_sequence_map = (prach_fmt<4) ? prach_root_sequence_map0_3 : prach_root_sequence_map4;
+  const uint16_t *prach_root_sequence_map = (prach_fmt < 4) ? prach_root_sequence_map0_3 : prach_root_sequence_map4;
   /*
   // this code is not part of get_prach_prb_offset
   if (frame_type == TDD) { // TDD
@@ -215,20 +210,6 @@ int32_t generate_prach( PHY_VARS_UE *ue, uint8_t eNB_id, uint8_t subframe, uint1
 #endif
   //  nsymb = (frame_parms->Ncp==0) ? 14:12;
   //  subframe_offset = (unsigned int)frame_parms->ofdm_symbol_size*subframe*nsymb;
-  k = (12*n_ra_prb) - 6*ue->frame_parms.N_RB_UL;
-
-  if (k<0)
-    k+=ue->frame_parms.ofdm_symbol_size;
-
-  k*=12;
-  k+=13;
-  Xu = (int16_t *)ue->X_u[preamble_offset-first_nonzero_root_idx];
-  /*
-    k+=(12*ue->frame_parms.first_carrier_offset);
-    if (k>(12*ue->frame_parms.ofdm_symbol_size))
-    k-=(12*ue->frame_parms.ofdm_symbol_size);
-  */
-  k*=2;
 
   switch (ue->frame_parms.N_RB_UL) {
     case 6:
@@ -259,20 +240,26 @@ int32_t generate_prach( PHY_VARS_UE *ue, uint8_t eNB_id, uint8_t subframe, uint1
 
       break;
   }
+  {
+    int k = (12 * n_ra_prb) - 6 * ue->frame_parms.N_RB_UL;
 
-  for (offset=0,offset2=0; offset<N_ZC; offset++,offset2+=preamble_shift) {
-    if (offset2 >= N_ZC)
-      offset2 -= N_ZC;
+    if (k < 0)
+      k += ue->frame_parms.ofdm_symbol_size;
 
-    Xu_re = (((int32_t)Xu[offset<<1]*amp)>>15);
-    Xu_im = (((int32_t)Xu[1+(offset<<1)]*amp)>>15);
-    prachF[k++]= ((Xu_re*ru[offset2<<1]) - (Xu_im*ru[1+(offset2<<1)]))>>15;
-    prachF[k++]= ((Xu_im*ru[offset2<<1]) + (Xu_re*ru[1+(offset2<<1)]))>>15;
+    k *= 12;
+    k += 13;
+    c16_t *Xu_ue = ue->X_u[preamble_offset - first_nonzero_root_idx];
+    c16_t *complex_prachF = (c16_t *)prachF;
+    for (int offset = 0, offset2 = 0; offset < N_ZC; offset++, offset2 += preamble_shift) {
+      if (offset2 >= N_ZC)
+        offset2 -= N_ZC;
+      c16_t Xu = c16mulRealShift(*Xu_ue++, amp, 15);
+      complex_prachF[k++] = c16mulShift(Xu, root_unit[offset2], 15);
 
-    if (k==(12*2*ue->frame_parms.ofdm_symbol_size))
-      k=0;
+      if (k == 12 * ue->frame_parms.ofdm_symbol_size)
+        k = 0;
+    }
   }
-
   switch (prach_fmt) {
     case 0:
       Ncp = 3168;
diff --git a/openair1/PHY/LTE_UE_TRANSPORT/transport_proto_ue.h b/openair1/PHY/LTE_UE_TRANSPORT/transport_proto_ue.h
index 9aab56e52a..06bf87fc74 100644
--- a/openair1/PHY/LTE_UE_TRANSPORT/transport_proto_ue.h
+++ b/openair1/PHY/LTE_UE_TRANSPORT/transport_proto_ue.h
@@ -1649,8 +1649,7 @@ void compute_prach_seq(uint16_t rootSequenceIndex,
                        uint8_t zeroCorrelationZoneConfig,
                        uint8_t highSpeedFlag,
                        frame_type_t frame_type,
-                       uint32_t X_u[64][839]);
-
+                       c16_t X_u[64][839]);
 
 void init_prach_tables(int N_ZC);
 
diff --git a/openair1/PHY/defs_UE.h b/openair1/PHY/defs_UE.h
index 17ae02610e..20d5a9ab8d 100644
--- a/openair1/PHY/defs_UE.h
+++ b/openair1/PHY/defs_UE.h
@@ -640,7 +640,7 @@ typedef struct {
   /// mbsfn reference symbols
   uint32_t         lte_gold_mbsfn_khz_1dot25_table[10][150];
 
-  uint32_t X_u[64][839];
+  c16_t X_u[64][839];
 
   uint32_t high_speed_flag;
   uint32_t perfect_ce;
diff --git a/openair1/PHY/defs_eNB.h b/openair1/PHY/defs_eNB.h
index 68ebf65462..98d1080ee3 100644
--- a/openair1/PHY/defs_eNB.h
+++ b/openair1/PHY/defs_eNB.h
@@ -600,8 +600,8 @@ typedef struct PHY_VARS_eNB_s {
   // PUCCH1a/b energy detection parameters for eMTC per CE-level
   int              pucch1ab_DTX_threshold_emtc[4];
 
-  uint32_t X_u[64][839];
-  uint32_t X_u_br[4][64][839];
+  c16_t X_u[64][839];
+  c16_t X_u_br[4][64][839];
   uint8_t pbch_configured;
   uint8_t pbch_pdu[4]; //PBCH_PDU_SIZE
   char eNB_generate_rar;