Merge remote-tracking branch 'origin/srs_phy_simulator' into integration_2026_w03 (!3718)

Introduce SRS physical simulator and improvements

This MR consists of two parts:

- Introduces SRS physical simulator to test different configurations of
  SRS
- Improvements in the SRS channel estimation (Addressing the comments
  from old, unfinished MR !2875)
  - rewrite nr_srs_channel_estimation() to loop over rx antennas and
    antenna ports to be able to parallelize
  - Improvements in timing_advance_offset and timing_advance_offset_nsec
    computation
  - Introduce SRS multi-symbol channel estimation
    - The channel impulse response is estimated from the averaged
      channel frequency response over multiple symbols
    - The channel frequency estimates are left as they are to be able to
      estimate doppler in the future
  - Simplify SRS channel estimation to handle memory alignment in the
    case of different SRS configurations (eg: comboffset)

To use multiple symbols when running gNB, the following parameters needs
to be edited in the function get_srs_resource()

- srs_res->resourceMapping.startPosition with a range from {0,1,..,5}
  corresponds to the start symbol {13, 12, .. 8} with in a slot
- srs_res->resourceMapping.nrofSymbols indicates the number of symbols
  {n1, n2, and n4}

Make sure the that start symbol + number of symbols is < 14

The timing results for SRS in develop and srs_phy_simulator are as follows:

Command used: sudo ./nr_ulsim -n1000 -s50 -S50 -R273 -W2 -y2 -z2 -E 1 -P

develop

|__ RX SRS time                            124.94 us (1000 trials)		(124.94 total [ms])
    |__ Generate SRS sequence time           0.05 us (1000 trials)		(  0.05 total [ms])
    |__ Get SRS signal time                 19.41 us (1000 trials)		( 19.41 total [ms])
    |__ SRS channel estimation time         89.11 us (1000 trials)		( 89.11 total [ms])
    |__ SRS timing advance estimation time  13.10 us (1000 trials)		( 13.10 total [ms])
    |__ SRS report TLV build time            2.80 us (1000 trials)		(  2.80 total [ms])
        |__ SRS beam report build time       0.00 us (  0 trials)
        |__ SRS IQ matrix build time         2.73 us (1000 trials)

srs_phy_simulator

|__ RX SRS time                            211.93 us (1000 trials)		(211.93 total [ms])
    |__ Generate SRS sequence time           0.04 us (1000 trials)		(  0.04 total [ms])
    |__ Get SRS signal time                 19.55 us (1000 trials)		( 19.55 total [ms])
    |__ SRS channel estimation time        152.05 us (1000 trials)		(152.05 total [ms])
    |__ SRS timing advance estimation time  36.67 us (1000 trials)		( 36.67 total [ms])
    |__ SRS report TLV build time            2.96 us (1000 trials)		(  2.96 total [ms])
        |__ SRS beam report build time       0.00 us (  0 trials)
        |__ SRS IQ matrix build time         2.88 us (1000 trials)

Note that in srs_phy_simulator, to compute timing offset ns, an
oversampling factor of 2 is performed. Also, for peak detection, we
average the channel estimates for every port.

common/utils/T/T_messages.txt

@@ -138,11 +138,11 @@ ID = GNB_PHY_UL_PAYLOAD_RX_BITS
 ID = GNB_PHY_UL_FREQ_CHANNEL_ESTIMATE
     DESC = gNodeB channel estimation in the frequency domain
     GROUP = ALL:PHY:GRAPHIC:HEAVY:GNB
-    FORMAT = int,gNB_ID : int,rnti : int,frame : int,subframe : int,antenna : buffer,chest_t
+    FORMAT = int,gNB_ID : int,rnti : int,frame : int,subframe : int,antenna : int,port : buffer,chest_f
 ID = GNB_PHY_UL_TIME_CHANNEL_ESTIMATE
     DESC = gNodeB channel estimation in the time domain
     GROUP = ALL:PHY:GRAPHIC:HEAVY:GNB
-    FORMAT = int,gNB_ID : int,rnti : int,frame : int,subframe : int,antenna : buffer,chest_t
+    FORMAT = int,gNB_ID : int,rnti : int,frame : int,subframe : int,antenna : int,port : buffer,chest_t
 ID = GNB_PHY_UL_SNR_ESTIMATE
     DESC = gNodeB SNR estimation based on SRS
     GROUP = ALL:PHY:GRAPHIC:HEAVY:GNB
@@ -155,6 +155,10 @@ ID = GNB_PHY_DL_OUTPUT_SIGNAL
     DESC = gNodeB output data in the freq domain for slots
     GROUP = ALL:PHY:GRAPHIC:HEAVY:GNB
     FORMAT = int,gNB_ID : int,frame : int,slot : int,antenna : buffer,txdata
+ID = GNB_PHY_UL_SRS_TOA_NS
+    DESC = gNB ToA estimate from SRS (in ns)
+    GROUP = ALL:PHY:GNB
+    FORMAT = int,gNB_ID : int,rnti : int,frame : int,subframe : buffer,toa_ns
 
 #MAC logs
 ID = ENB_MAC_UE_DL_SDU

common/utils/nr/nr_common.h

@@ -360,6 +360,7 @@ float get_beta_dmrs(int num_cdm_groups_no_data, bool is_type2);
 
 #define CEILIDIV(a,b) ((a+b-1)/b)
 #define ROUNDIDIV(a,b) (((a<<1)+b)/(b<<1))
+#define BOUNDED_EVAL(a, b, c) (min(c, max(a, b)))
 
 static const char *const duplex_mode_txt[] = {"FDD", "TDD"};