radio/vrtsim: Add CIRDB support for precomputed channel taps

Integrate Channel Impulse Response Database (CIRDB) to enable playback of precomputed realistic channel taps in vrtsim, with runtime selection via YAML metadata. Features: - Read precomputed channel taps from binary database with YAML sidecar - Runtime enable via --vrtsim.cirdb with optional paths (cirdb_yaml, cirdb_file, cirdb_path) - Channel parameter configuration: model_id (TDL-A..E), delay spread (ds_ns), UE speed (speed_mps) - Fallback to existing channel model options when disabled - Time-driven snapshot progression based on elapsed simulation time Fixes: - RNG initialization: Add randominit() call before gaussZiggurat() - FlatBuffers linking: Handle both 'FlatBuffers' and 'flatbuffers' package names when working with external channel emmulator - Address review comments: use pthread directly, update calloc_or_fail, simplify CMake
2026-02-09 23:22:40 -08:00
parent 9777d23173
commit ccf5021072
7 changed files with 745 additions and 10 deletions
@@ -0,0 +1,152 @@
+/*
+ * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The OpenAirInterface Software Alliance licenses this file to You under
+ * the OAI Public License, Version 1.1  (the "License"); you may not use this file
+ * except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.openairinterface.org/?page_id=698
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *-------------------------------------------------------------------------------
+ * For more information about the OpenAirInterface (OAI) Software Alliance:
+ *      contact@openairinterface.org
+ */
+
+#include "cirdb_yaml.h"
+#include <yaml-cpp/yaml.h>
+#include <cmath>
+#include <string>
+extern "C" {
+#include "common/utils/LOG/log.h"
+}
+
+static inline double dabs(double x)
+{
+  return x < 0 ? -x : x;
+}
+
+int cirdb_yaml_scan(const char *yaml_path)
+{
+  YAML::Node root;
+  try {
+    root = YAML::LoadFile(yaml_path);
+  } catch (const YAML::Exception &e) {
+    LOG_E(HW, "CIRDB YAML parse error in %s: %s\n", yaml_path, e.what());
+    return -1;
+  }
+  auto ents = root["entries"];
+  if (!ents || !ents.IsSequence()) {
+    LOG_E(HW, "CIRDB YAML: missing or invalid 'entries' in %s\n", yaml_path);
+    return -1;
+  }
+
+  int n = static_cast<int>(ents.size());
+  LOG_I(HW, "CIRDB YAML: %d entries in %s\n", n, yaml_path);
+  return n;
+}
+
+int cirdb_yaml_select(const cirdb_select_req_t *req, cirdb_entry_meta_t *out)
+{
+  if (!req || !out || !req->yaml_path) {
+    LOG_E(HW, "CIRDB YAML: invalid arguments to cirdb_yaml_select\n");
+    return -1;
+  }
+
+  YAML::Node root;
+  try {
+    root = YAML::LoadFile(req->yaml_path);
+  } catch (const YAML::Exception &e) {
+    LOG_E(HW, "CIRDB YAML parse error in %s: %s\n", req->yaml_path, e.what());
+    return -1;
+  }
+
+  auto ents = root["entries"];
+  if (!ents || !ents.IsSequence()) {
+    LOG_E(HW, "CIRDB YAML: missing or invalid 'entries' in %s\n", req->yaml_path);
+    return -1;
+  }
+
+  bool found = false;
+  double best_cost = 1e300;
+  cirdb_entry_meta_t best{};
+
+  // Determine if specific parameters are required
+  bool want_specific_model = (req->want_model_id >= 0);
+  bool want_specific_antennas = (req->want_tx > 0 && req->want_rx > 0);
+
+  for (std::size_t i = 0; i < ents.size(); ++i) {
+    const YAML::Node e = ents[i];
+    int pair_order = e["pair_order"].as<int>(0);
+
+    int model_id = e["model_id"].as<int>(-1);
+
+    // STRICT: model_id must match if specified
+    if (want_specific_model && model_id != req->want_model_id)
+      continue;
+
+    int n_tx = e["n_tx"].as<int>(0);
+    int n_rx = e["n_rx"].as<int>(0);
+
+    // STRICT: antenna dimensions must match exactly if specified
+    bool shape_ok = true;
+    if (want_specific_antennas) {
+      shape_ok = (n_tx == req->want_tx && n_rx == req->want_rx);
+      bool shape_swap_ok = req->allow_shape_swap ? (n_tx == req->want_rx && n_rx == req->want_tx) : false;
+      shape_ok = shape_ok || shape_swap_ok;
+
+      if (!shape_ok)
+        continue; // Skip entries with wrong antenna configuration
+    }
+
+    // STRICT: antenna dimensions must match exactly if specified
+    if (want_specific_antennas) {
+      if (n_tx != req->want_tx || n_rx != req->want_rx)
+        continue; // Skip entries with wrong antenna configuration
+    }
+
+    float ds_ns = e["ds_ns"].as<float>(0.0f);
+    float sp = e["speed_mps"].as<float>(0.0f);
+
+    // FLEXIBLE: delay spread and speed - find closest match using cost function
+    double cds = 0.0;
+    double csp = 0.0;
+
+    if (req->want_ds_ns > 0)
+      cds = dabs((double)ds_ns - (double)req->want_ds_ns);
+
+    if (req->want_speed_mps > 0)
+      csp = dabs((double)sp - (double)req->want_speed_mps);
+
+    double cost = (req->w_ds > 0 ? req->w_ds : 1.0) * cds + (req->w_speed > 0 ? req->w_speed : 0.2) * csp;
+
+    if (!found || cost < best_cost) {
+      best_cost = cost;
+      found = true;
+
+      best.model_id = model_id;
+      best.n_tx = n_tx;
+      best.n_rx = n_rx;
+      best.L = e["L"].as<int>(0);
+      best.S = e["S"].as<int>(0);
+      best.fs_hz = e["fs_hz"].as<double>(0.0);
+      best.snapshot_dt_s = e["snapshot_dt_s"].as<double>(0.0);
+      best.ds_ns = ds_ns;
+      best.speed_mps = sp;
+      best.pair_order = pair_order;
+      best.offset_bytes = e["offset_bytes"].as<uint64_t>(0);
+      best.nbytes = e["nbytes"].as<uint64_t>(0);
+    }
+  }
+
+  if (!found)
+    return 0;
+  *out = best;
+  return 1;
+}