diff --git a/pytest.ini b/pytest.ini
index dea91f8..eea2c18 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -1 +1 @@
-"""Pytest markers used by optional, physical lab tests."""
+[pytest]
diff --git a/src/vulture/chemical_rf/__init__.py b/src/vulture/chemical_rf/__init__.py
index 9739459..5e04527 100644
--- a/src/vulture/chemical_rf/__init__.py
+++ b/src/vulture/chemical_rf/__init__.py
@@ -8,6 +8,7 @@ copying or deleting its public API.
 from __future__ import annotations
 
 import importlib.util
+import sys
 from pathlib import Path
 
 _legacy_path = Path(__file__).resolve().parents[1] / "chemical_rf.py"
@@ -15,6 +16,7 @@ _spec = importlib.util.spec_from_file_location("vulture._chemical_rf_legacy", _l
 if _spec is None or _spec.loader is None:
     raise ImportError(f"cannot load legacy Chemical-RF module: {_legacy_path}")
 _legacy = importlib.util.module_from_spec(_spec)
+sys.modules[_spec.name] = _legacy  # required for dataclasses on Python 3.14+
 _spec.loader.exec_module(_legacy)
 
 ChemicalBond = _legacy.ChemicalBond
@@ -26,7 +28,7 @@ from .calibration import ImpedanceCalibrator, LinearCalibration, combine_uncerta
 from .models import CalibrationPoint, ExperimentRecord, Measurement
 from .materials import (
     complex_permittivity, dielectric_resonance_frequency,
-    maxwell_garnett_permittivity, reflection_coefficient,
+    maxwell_garnett_permittivity, reflection_coefficient, absorption_coefficient,
 )
 from .pipeline import ChemicalRFAnalysisPipeline, ChemicalRFReport
 from .spectroscopy import larmor_frequency_hz, simulate_fid, spectrum_from_fid
@@ -36,6 +38,7 @@ __all__ = [
     "CalibrationPoint", "ExperimentRecord", "Measurement", "ImpedanceCalibrator",
     "LinearCalibration", "combine_uncertainty", "complex_permittivity",
     "dielectric_resonance_frequency", "maxwell_garnett_permittivity",
-    "reflection_coefficient", "ChemicalRFAnalysisPipeline", "ChemicalRFReport",
+    "reflection_coefficient", "absorption_coefficient",
+    "ChemicalRFAnalysisPipeline", "ChemicalRFReport",
     "larmor_frequency_hz", "simulate_fid", "spectrum_from_fid",
 ]
diff --git a/src/vulture/chemical_rf/materials.py b/src/vulture/chemical_rf/materials.py
index 4f26b1b..a2941e7 100644
--- a/src/vulture/chemical_rf/materials.py
+++ b/src/vulture/chemical_rf/materials.py
@@ -31,8 +31,15 @@ def dielectric_resonance_frequency(epsilon_r: float, length_m: float, mode: int
 
 
 
-def absorption_coefficient(load_ohm: complex, reference_ohm: complex = 50 + 0j) -> complex:
+def reflection_coefficient(load_ohm: complex, reference_ohm: complex = 50 + 0j) -> complex:
+    """Return the complex reflection coefficient Γ = (Z_L - Z_0) / (Z_L + Z_0)."""
     if reference_ohm == 0:
         raise ValueError("reference impedance cannot be zero")
-    return 2 * np.abs(reflection_coefficient(load_ohm, reference_ohm))**2 / (1 + np.abs(reflection_coefficient(load_ohm, reference_ohm))**2)
+    return (load_ohm - reference_ohm) / (load_ohm + reference_ohm)
+
+
+def absorption_coefficient(load_ohm: complex, reference_ohm: complex = 50 + 0j) -> float:
+    """Return the power absorption coefficient derived from the reflection coefficient."""
+    gamma = reflection_coefficient(load_ohm, reference_ohm)
+    return 1 - abs(gamma) ** 2
 
diff --git a/src/vulture/cli.py b/src/vulture/cli.py
index 7004dd9..e7eb8c3 100644
--- a/src/vulture/cli.py
+++ b/src/vulture/cli.py
@@ -15,6 +15,7 @@ import click
 from vulture.chemical_rf.science import free_space_path_loss_db, wavelength_m
 from vulture.chemical_rf.spectroscopy import larmor_frequency_hz
 from vulture.forensics import audit_chemistry, audit_mathematics, audit_physics, audit_protocol
+from vulture.lab_cli import lab_cli
 
 
 @click.group(invoke_without_command=True)
@@ -28,6 +29,9 @@ def cli(ctx: click.Context, interactive: bool) -> None:
         click.echo(ctx.get_help())
 
 
+cli.add_command(lab_cli, name="lab")
+
+
 @cli.command()
 def info() -> None:
     """Display platform capabilities."""
diff --git a/src/vulture/forensics/__init__.py b/src/vulture/forensics/__init__.py
index c63255b..a28a790 100644
--- a/src/vulture/forensics/__init__.py
+++ b/src/vulture/forensics/__init__.py
@@ -1,6 +1,23 @@
-from .forensics import (
-    Finding, ForensicReport, audit_chemistry, audit_mathematics,
-    audit_physics, audit_protocol, write_report,
-)
+from __future__ import annotations
+
+import importlib.util
+import sys
+from pathlib import Path
+
+_legacy_path = Path(__file__).resolve().parents[1] / "forensics.py"
+_spec = importlib.util.spec_from_file_location("vulture._forensics_legacy", _legacy_path)
+if _spec is None or _spec.loader is None:
+    raise ImportError(f"cannot load legacy forensics module: {_legacy_path}")
+_legacy = importlib.util.module_from_spec(_spec)
+sys.modules[_spec.name] = _legacy
+_spec.loader.exec_module(_legacy)
+
+Finding = _legacy.Finding
+ForensicReport = _legacy.ForensicReport
+audit_chemistry = _legacy.audit_chemistry
+audit_mathematics = _legacy.audit_mathematics
+audit_physics = _legacy.audit_physics
+audit_protocol = _legacy.audit_protocol
+write_report = _legacy.write_report
 
 __all__ = ["Finding", "ForensicReport", "audit_chemistry", "audit_mathematics", "audit_physics", "audit_protocol", "write_report"]
diff --git a/src/vulture/lab/__init__.py b/src/vulture/lab/__init__.py
index e8214c2..58bb1d6 100644
--- a/src/vulture/lab/__init__.py
+++ b/src/vulture/lab/__init__.py
@@ -1,3 +1,19 @@
-from .lab import LabResult, attack_simulation, defense_simulation
+from __future__ import annotations
+
+import importlib.util
+import sys
+from pathlib import Path
+
+_legacy_path = Path(__file__).resolve().parents[1] / "lab.py"
+_spec = importlib.util.spec_from_file_location("vulture._lab_legacy", _legacy_path)
+if _spec is None or _spec.loader is None:
+    raise ImportError(f"cannot load legacy lab module: {_legacy_path}")
+_legacy = importlib.util.module_from_spec(_spec)
+sys.modules[_spec.name] = _legacy
+_spec.loader.exec_module(_legacy)
+
+LabResult = _legacy.LabResult
+attack_simulation = _legacy.attack_simulation
+defense_simulation = _legacy.defense_simulation
 
 __all__ = ["LabResult", "attack_simulation", "defense_simulation"]
diff --git a/src/vulture/physics_laboratory/physics_laboratory.py b/src/vulture/physics_laboratory/physics_laboratory.py
index a2514c7..f6f8c23 100644
--- a/src/vulture/physics_laboratory/physics_laboratory.py
+++ b/src/vulture/physics_laboratory/physics_laboratory.py
@@ -73,7 +73,7 @@ class LinkBudget:
             'erp_dbm': erp,
             'received_power_dbm': rx_power,
             'path_loss_db': path_loss_db,
-            'margin_db': margin,
+            'link_margin_db': margin,
             'link_available': margin > -120  # Typical sensitivity
         }
     
@@ -309,39 +309,6 @@ class RadarSimulator:
             'velocity_ms': target_velocity_ms,
             'shifted_frequency_hz': frequency + doppler_freq
         }
-    def calculate_radar_range(self, tx_power_dbm: float, frequency: float,):
-        """Calculate maximum radar range"""
-        callable_radar_ranger = lambda antenna_gain_db, rcs_dbsm : self.calculate_radar_range(tx_power_dbm, frequency, antenna_gain_db, rcs_dbsm)
-        return callable_radar_ranger
-        if antenna_gain_db == 0 and rcs_dbsm == 0:
-            return {
-                'max_range_m': 0,
-                'max_range_km': 0,
-                'range_resolution_m': 0
-            }
-
-        else:
-            raise ValueError("Antenna gain and RCS must be positive values")
-    def calculate_doppler_shift(self, target_velocity_ms: float, frequency: float):
-        """Calculate Doppler shift"""
-        callable_doppler_shift = lambda : self.doppler_shift(target_velocity_ms, frequency)
-        np.random.seed(42)
-        return callable_doppler_shift
-        if target_velocity_ms == 0 or frequency == 0:
-            return {
-                'doppler_shift_hz': 0,
-                'velocity_ms': 0,
-                'shifted_frequency_hz': frequency
-            }
-        else:
-            raise ValueError("Target velocity and frequency must be positive values")
-    def calculate_signal_path(self, tx_power_dbm: float, frequency: float,):
-        """Calculate complete signal path"""
-        callable_signal_path = lambda tx_antenna_gain_db, rx_antenna_gain_db, distance, environmental_loss_db : self.calculate_signal_path(tx_power_dbm, frequency, tx_antenna_gain_db, rx_antenna_gain_db, distance, environmental_loss_db)
-        return callable_signal_path
-    def calculate_radar_range(self, tx_power_dbm: float, frequency: float, antenna_gain_db: float, rcs_dbsm: float, receiver_sensitivity_dbm: float = -110):
-        """Calculate maximum radar range"""
-        return self.calculate_radar_range(tx_power_dbm, frequency, antenna_gain_db, rcs_dbsm, receiver_sensitivity_dbm)
 
 
 
diff --git a/src/vulture/rf_dna/fingerprint.py b/src/vulture/rf_dna/fingerprint.py
index 6c37cf3..2bfed82 100644
--- a/src/vulture/rf_dna/fingerprint.py
+++ b/src/vulture/rf_dna/fingerprint.py
@@ -29,8 +29,8 @@ def extract_fingerprint(iq: np.ndarray, sample_rate: float) -> Fingerprint:
         raise ValueError("IQ must be non-empty and finite; sample_rate must be positive")
     amp = np.abs(x).astype(np.float64)
     power = amp * amp
-    spectrum = np.abs(np.fft.rfft(x)) ** 2
-    frequencies = np.fft.rfftfreq(x.size, 1.0 / sample_rate)
+    spectrum = np.abs(np.fft.fft(x)) ** 2
+    frequencies = np.fft.fftfreq(x.size, 1.0 / sample_rate)
     total = float(spectrum.sum())
     centroid = float((frequencies * spectrum).sum() / total) if total else 0.0
     spread = float(np.sqrt(((frequencies - centroid) ** 2 * spectrum).sum() / total)) if total else 0.0
@@ -53,8 +53,6 @@ def similarity(left: Fingerprint, right: Fingerprint) -> float:
     b = np.array([right.mean_amplitude, right.rms_amplitude, right.crest_factor, right.spectral_centroid_hz, right.spectral_spread_hz], dtype=float)
     scale = np.maximum(np.maximum(np.abs(a), np.abs(b)), 1e-12)
     distance = float(np.mean(np.abs(a - b) / scale))
-    c = np.array([left.sample_count, right.sample_count], dtype=float)
-    d = np.array([left.digest, right.digest], dtype=np.uint8)
     return float(max(0.0, min(1.0, 1.0 - distance)))
 
 
diff --git a/src/vulture/timeseries_framework/timeseries_engine.py b/src/vulture/timeseries_framework/timeseries_engine.py
index c4b21ae..c655672 100644
--- a/src/vulture/timeseries_framework/timeseries_engine.py
+++ b/src/vulture/timeseries_framework/timeseries_engine.py
@@ -20,7 +20,10 @@ class TimeSeriesEngine:
         """Add data with circular buffer."""
         data = np.asarray(data)
         n = len(data)
-        if self.position + n <= self.buffer_size:
+        if n >= self.buffer_size:
+            self.buffer[:] = data[-self.buffer_size:]
+            self.position = self.buffer_size
+        elif self.position + n <= self.buffer_size:
             self.buffer[self.position:self.position+n] = data
             self.position += n
         else:
diff --git a/tests/conftest.py b/tests/conftest.py
index afc676c..f513bb0 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,15 +1,62 @@
 """Conftest for pytest configuration."""
 import pytest
 import numpy as np
+from scipy import signal
+
 
 @pytest.fixture
 def sample_signal():
-    return np.sin(2 * np.pi * 0.1 * np.arange(1000))
+    t = np.arange(0, 1, 1/1e6)
+    return np.sin(2*np.pi*1e3*t) + 0.1*np.random.randn(len(t))
+
 
 @pytest.fixture
 def iq_data():
-    return np.exp(1j * 2 * np.pi * 0.1 * np.arange(1000))
+    t = np.arange(0, 1, 1/1e6)
+    return np.exp(1j * 2*np.pi*1e3*t) + 0.05*np.random.randn(len(t))
+
 
 @pytest.fixture
 def random_data():
-    return np.random.randn(1000)
+    return np.random.randn(10000)
+
+
+@pytest.fixture
+def bpsk_signal():
+    bits = np.random.randint(0, 2, 1000)
+    symbols = 2*bits - 1
+    t = np.arange(0, len(symbols)*10, 1)
+    carrier = np.sin(2*np.pi*0.01*t)
+    return (np.repeat(symbols, 10) * carrier)
+
+
+@pytest.fixture
+def qpsk_signal():
+    bits = np.random.randint(0, 4, 1000)
+    symbols = np.exp(1j * np.pi/2 * bits)
+    return np.repeat(symbols, 100)
+
+
+@pytest.fixture
+def chirp_signal():
+    t = np.linspace(0, 1, int(1e6))
+    return signal.chirp(t, 100, 1, 1000)
+
+
+@pytest.fixture
+def burst_signal():
+    t = np.arange(0, 1, 1/1e6)
+    burst1 = np.sin(2*np.pi*1e3*t[0:200000])
+    silence = np.zeros(300000)
+    burst2 = np.sin(2*np.pi*1e3*t[0:200000])
+    burst3 = np.zeros(300000)
+    return np.concatenate([burst1, silence, burst2, burst3])
+
+
+@pytest.fixture
+def multipath_signal():
+    t = np.arange(0, 1, 1/1e6)
+    direct = np.sin(2*np.pi*1e3*t)
+    path1 = 0.5*np.sin(2*np.pi*1e3*(t-0.0001))
+    path2 = 0.3*np.sin(2*np.pi*1e3*(t-0.0002))
+    return direct + path1 + path2