band_helper: add function to retrieve n_ta_offset value from band

Author: andrepuschmann

include/srsran/ran/band_helper.h

@@ -15,6 +15,7 @@
 
 #include "srsran/adt/expected.h"
 #include "srsran/adt/optional.h"
+#include "srsran/ran/n_ta_offset.h"
 #include "srsran/ran/ssb_properties.h"
 #include <stdint.h>
 
@@ -288,6 +289,11 @@ unsigned get_nof_coreset0_rbs_not_intersecting_ssb(unsigned              cset0_i
                                                    ssb_offset_to_pointA  offset_to_point_A,
                                                    ssb_subcarrier_offset k_ssb);
 
+/// \brief Returns the n_ta_offset for a given band.
+/// \param[in] band is <em>NR operating band<\em>, as per TS 38.104, Table 5.2-1. Only FR1 values are supported.
+/// \return Value of n_ta_offset.
+n_ta_offset get_ta_offset(nr_band band);
+
 } // namespace band_helper
 
 } // namespace srsran

lib/ran/band_helper.cpp

@@ -765,3 +765,13 @@ unsigned srsran::band_helper::get_nof_coreset0_rbs_not_intersecting_ssb(unsigned
                                    crb_ssb_0 - cset0_cfg.offset + cset0_cfg.nof_rb_coreset};
   return cset0_cfg.nof_rb_coreset - cset0_prbs.intersect(ssb_prbs).length();
 }
+
+n_ta_offset srsran::band_helper::get_ta_offset(nr_band band)
+{
+  if (get_freq_range(band) == frequency_range::FR1) {
+    // assume no LTE-NR coexistence
+    return n_ta_offset::n25600;
+  } else {
+    return n_ta_offset::n13792;
+  }
+}