@mytec: iter1.6.1 ready for testing

backend/app/services/indoor_service.py

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+import math
+
+
+class IndoorService:
+    """ITU-R P.2109 building entry loss model"""
+
+    # Building Entry Loss (BEL) by construction type at 2 GHz
+    # Format: (median_loss_dB, std_dev_dB)
+    BUILDING_TYPES = {
+        "none": (0.0, 0.0),           # Outdoor only
+        "light": (8.0, 4.0),          # Wood frame, large windows
+        "medium": (15.0, 6.0),        # Brick, standard windows
+        "heavy": (22.0, 8.0),         # Concrete, small windows
+        "basement": (30.0, 10.0),     # Underground
+        "vehicle": (6.0, 3.0),        # Inside car
+        "train": (20.0, 5.0),         # Inside train
+    }
+
+    # Frequency correction factor (dB per octave above 2 GHz)
+    FREQ_CORRECTION = 2.5
+
+    def calculate_indoor_loss(
+        self,
+        frequency_mhz: float,
+        building_type: str = "medium",
+        floor_number: int = 0,
+        depth_m: float = 0.0,
+    ) -> float:
+        """
+        Calculate building entry/indoor penetration loss
+
+        Args:
+            frequency_mhz: Frequency in MHz
+            building_type: Type of building construction
+            floor_number: Floor number (0=ground, negative=basement)
+            depth_m: Distance from exterior wall in meters
+
+        Returns:
+            Loss in dB
+        """
+        if building_type == "none":
+            return 0.0
+
+        base_loss, _ = self.BUILDING_TYPES.get(building_type, (15.0, 6.0))
+
+        # Frequency correction
+        freq_ghz = frequency_mhz / 1000
+        if freq_ghz > 2.0:
+            octaves = math.log2(freq_ghz / 2.0)
+            freq_correction = self.FREQ_CORRECTION * octaves
+        else:
+            freq_correction = 0.0
+
+        # Floor correction (higher floors = less loss due to better angle)
+        if floor_number > 0:
+            floor_correction = -1.5 * min(floor_number, 10)
+        elif floor_number < 0:
+            # Basement - additional loss
+            floor_correction = 5.0 * abs(floor_number)
+        else:
+            floor_correction = 0.0
+
+        # Depth correction (signal attenuates inside building)
+        # Approximately 0.5 dB per meter for first 10m
+        depth_correction = 0.5 * min(depth_m, 20)
+
+        total_loss = base_loss + freq_correction + floor_correction + depth_correction
+
+        return max(0.0, min(total_loss, 50.0))  # Clamp 0-50 dB
+
+    def calculate_outdoor_to_indoor_coverage(
+        self,
+        outdoor_rsrp: float,
+        building_type: str,
+        frequency_mhz: float,
+    ) -> float:
+        """Calculate expected indoor RSRP from outdoor signal"""
+        indoor_loss = self.calculate_indoor_loss(frequency_mhz, building_type)
+        return outdoor_rsrp - indoor_loss
+
+
+indoor_service = IndoorService()