From e4696fec3871ee1ff0e3b05ab66ebc2626fb6643 Mon Sep 17 00:00:00 2001
From: Ismael Gomez <ismagom@gmail.com>
Date: Wed, 3 Jan 2018 18:07:23 +0100
Subject: [PATCH] Added ue location calculation for a particular L

---
 lib/include/srslte/phy/phch/pdcch.h | 10 ++++++-
 lib/src/phy/phch/pdcch.c            | 45 +++++++++++++++++------------
 2 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/lib/include/srslte/phy/phch/pdcch.h b/lib/include/srslte/phy/phch/pdcch.h
index 9bb896b34..0e0e63335 100644
--- a/lib/include/srslte/phy/phch/pdcch.h
+++ b/lib/include/srslte/phy/phch/pdcch.h
@@ -167,7 +167,15 @@ SRSLTE_API uint32_t srslte_pdcch_ue_locations(srslte_pdcch_t *q,
 SRSLTE_API uint32_t srslte_pdcch_ue_locations_ncce(uint32_t nof_cce, 
                                                    srslte_dci_location_t *c, 
                                                    uint32_t max_candidates, 
-                                                   uint32_t nsubframe, uint16_t rnti); 
+                                                   uint32_t nsubframe,
+                                                   uint16_t rnti);
+
+SRSLTE_API uint32_t srslte_pdcch_ue_locations_ncce_L(uint32_t nof_cce,
+                                                     srslte_dci_location_t *c,
+                                                     uint32_t max_candidates,
+                                                     uint32_t nsubframe,
+                                                     uint16_t rnti,
+                                                     int L);
 
 /* Function for generation of common search space DCI locations */
 SRSLTE_API uint32_t srslte_pdcch_common_locations(srslte_pdcch_t *q, 
diff --git a/lib/src/phy/phch/pdcch.c b/lib/src/phy/phch/pdcch.c
index 58d5bf6db..ca8480bc6 100644
--- a/lib/src/phy/phch/pdcch.c
+++ b/lib/src/phy/phch/pdcch.c
@@ -218,13 +218,20 @@ uint32_t srslte_pdcch_ue_locations(srslte_pdcch_t *q, srslte_dci_location_t *c,
   return srslte_pdcch_ue_locations_ncce(q->nof_cce, c, max_candidates, nsubframe, rnti);
 }
 
+
+uint32_t srslte_pdcch_ue_locations_ncce(uint32_t nof_cce, srslte_dci_location_t *c, uint32_t max_candidates,
+                                        uint32_t nsubframe, uint16_t rnti)
+{
+  return srslte_pdcch_ue_locations_ncce_L(nof_cce, c, max_candidates, nsubframe, rnti, -1);
+}
+
 /** 36.213 v9.1.1 
  * Computes up to max_candidates UE-specific candidates for DCI messages and saves them 
  * in the structure pointed by c.
  * Returns the number of candidates saved in the array c.   
  */
-uint32_t srslte_pdcch_ue_locations_ncce(uint32_t nof_cce, srslte_dci_location_t *c, uint32_t max_candidates,
-                        uint32_t nsubframe, uint16_t rnti) {
+uint32_t srslte_pdcch_ue_locations_ncce_L(uint32_t nof_cce, srslte_dci_location_t *c, uint32_t max_candidates,
+                        uint32_t nsubframe, uint16_t rnti, int Ls) {
   
   int l; // this must be int because of the for(;;--) loop
   uint32_t i, k, L, m; 
@@ -241,24 +248,26 @@ uint32_t srslte_pdcch_ue_locations_ncce(uint32_t nof_cce, srslte_dci_location_t
   // All aggregation levels from 8 to 1
   for (l = 3; l >= 0; l--) {
     L = (1 << l);
-    // For all candidates as given in table 9.1.1-1
-    for (i = 0; i < nof_candidates[l]; i++) {
-      if (nof_cce >= L) {
-        ncce = L * ((Yk + i) % (nof_cce / L));
-        // Check if candidate fits in c vector and in CCE region
-        if (k < max_candidates  && ncce + L <= nof_cce) 
-        {            
-          c[k].L = l;
-          c[k].ncce = ncce;
-          
-          DEBUG("UE-specific SS Candidate %d: nCCE: %d, L: %d\n",
-              k, c[k].ncce, c[k].L);            
-
-          k++;          
-        } 
+    if (Ls<0 || Ls==L) {
+      // For all candidates as given in table 9.1.1-1
+      for (i = 0; i < nof_candidates[l]; i++) {
+        if (nof_cce >= L) {
+          ncce = L * ((Yk + i) % (nof_cce / L));
+          // Check if candidate fits in c vector and in CCE region
+          if (k < max_candidates  && ncce + L <= nof_cce)
+          {
+            c[k].L = l;
+            c[k].ncce = ncce;
+
+            DEBUG("UE-specific SS Candidate %d: nCCE: %d, L: %d\n",
+                  k, c[k].ncce, c[k].L);
+
+            k++;
+          }
+        }
       }
     }
-  }    
+  }
 
   DEBUG("Initiated %d candidate(s) in the UE-specific search space for C-RNTI: 0x%x, nsubframe=%d, nof_cce=%d\n", 
          k, rnti, nsubframe, nof_cce);