Tutorial: Extract CSI For One Position¶
This notebook shows how to:
- choose a measurement position
- resolve that position to a cycle ID
- extract the complex CSI vector for that cycle
- plot the phase and power on the antenna plane
A position in the RF xarray is represented by an experiment_id and cycle_id pair.
# Optional: uncomment when this Jupyter kernel misses the plotting dependencies.
# import sys
# !{sys.executable} -m pip install matplotlib numpy requests xarray pyyaml
from pathlib import Path
import importlib.util
import sys
import matplotlib.pyplot as plt
NOTEBOOK_DIR = Path.cwd().resolve()
for candidate_dir in (
NOTEBOOK_DIR,
NOTEBOOK_DIR / "tutorials",
NOTEBOOK_DIR / "processing" / "tutorials",
):
if (candidate_dir / "csi_plot_utils.py").exists():
NOTEBOOK_DIR = candidate_dir.resolve()
break
else:
raise ImportError(f"Could not locate csi_plot_utils.py from {Path.cwd().resolve()}")
UTILS_PATH = NOTEBOOK_DIR / "csi_plot_utils.py"
PROCESSING_DIR = NOTEBOOK_DIR.parent
PROJECT_ROOT = PROCESSING_DIR.parent
spec = importlib.util.spec_from_file_location("csi_plot_utils", UTILS_PATH)
if spec is None or spec.loader is None:
raise ImportError(f"Could not load utility module from {UTILS_PATH}")
csi = importlib.util.module_from_spec(spec)
sys.modules["csi_plot_utils"] = csi
spec.loader.exec_module(csi)
EXPERIMENT_ID = "EXP003"
DATASET_PATH = None
SELECTED_CYCLE_ID = None # Set an integer cycle ID to override the automatic selection.
TARGET_POSITION = None # Example: {"x": 1.20, "y": 2.40, "z": None}
HEATMAP_MAX_CYCLE_VALUES = csi.DEFAULT_HEATMAP_MAX_CYCLE_VALUES
ds, dataset_path = csi.open_dataset(experiment_id=EXPERIMENT_ID, dataset_path=DATASET_PATH)
antenna_positions = csi.load_antenna_positions()
available_cycles = csi.available_cycle_ids(ds, EXPERIMENT_ID)
print(f"Loaded dataset: {dataset_path}")
print(f"CSI cycles available: {available_cycles.size}")
if TARGET_POSITION is not None:
nearest = csi.find_nearest_position_cycle(
ds,
EXPERIMENT_ID,
x=TARGET_POSITION["x"],
y=TARGET_POSITION["y"],
z=TARGET_POSITION.get("z"),
)
SELECTED_CYCLE_ID = int(nearest["cycle_id"])
print("Selected the nearest recorded cycle for the requested point:")
print(nearest)
elif SELECTED_CYCLE_ID is None:
SELECTED_CYCLE_ID = int(available_cycles[0])
print(f"Using the first cycle with CSI: {SELECTED_CYCLE_ID}")
else:
SELECTED_CYCLE_ID = int(SELECTED_CYCLE_ID)
position = csi.cycle_position(ds, EXPERIMENT_ID, SELECTED_CYCLE_ID)
print("Rover position for the selected cycle:")
position
Loaded dataset: C:\Users\Calle\OneDrive\Documenten\GitHub\ELLIIIT-dataset-26\results\csi_EXP003__EXP005__EXP006__EXP007__EXP008__EXP009__EXP010__EXP011__EXP012.nc CSI cycles available: 529 Using the first cycle with CSI: 1 Rover position for the selected cycle:
{'experiment_id': 'EXP003',
'cycle_id': 1,
'position_available': True,
'rover_x': 1.9183037109375,
'rover_y': 2.865016845703125,
'rover_z': 0.7394267578125,
'csi_host_count': 42}
Extract The CSI Vector¶
The helper below returns one xarray dataset with one entry per hostname. It includes the complex CSI components, derived amplitude and power, and the mapped antenna coordinates.
snapshot = csi.extract_csi_snapshot(
ds,
EXPERIMENT_ID,
SELECTED_CYCLE_ID,
antenna_positions=antenna_positions,
)
print(
f"Extracted {snapshot.sizes['hostname']} CSI values "
f"for experiment {EXPERIMENT_ID}, cycle {SELECTED_CYCLE_ID}"
)
snapshot
Extracted 42 CSI values for experiment EXP003, cycle 1
<xarray.Dataset> Size: 3kB
Dimensions: (hostname: 42)
Coordinates:
* hostname (hostname) <U3 504B 'G05' 'F05' 'E05' ... 'C10' 'B10' 'A10'
Data variables:
csi_real (hostname) float64 336B 0.002539 -0.002133 ... 0.003275
csi_imag (hostname) float64 336B 0.000818 -4.723e-05 ... 0.007729
csi_amplitude (hostname) float64 336B 0.002668 0.002133 ... 0.008394
csi_power_db (hostname) float64 336B -51.48 -53.42 ... -52.43 -41.52
csi_phase_deg (hostname) float64 336B 17.86 -178.7 -69.94 ... -105.5 67.04
antenna_x (hostname) float64 336B 0.35 1.55 2.75 ... 5.15 6.35 7.55
antenna_y (hostname) float64 336B 0.66 0.66 0.66 ... 3.66 3.66 3.66
antenna_z (hostname) float64 336B 2.4 2.4 2.4 2.4 ... 2.4 2.4 2.4 2.4
Attributes:
experiment_id: EXP003
cycle_id: 1
position_available: True
rover_x: 1.9183037109375
rover_y: 2.865016845703125
rover_z: 0.7394267578125
csi_host_count: 42Plot The Selected Position On The Antenna Plane¶
The red star is the rover location for the selected cycle. The antenna tiles are colored by the extracted CSI values for that same cycle.
csi.plot_spatial_phase_snapshot(snapshot)
plt.show()
csi.plot_spatial_power_snapshot(snapshot)
plt.show()
Use The Full Heatmaps To Choose Another Cycle¶
These plots show the last HEATMAP_MAX_CYCLE_VALUES cycle values and are useful when you want to pick a different cycle before extracting another CSI snapshot.
csi.plot_phase_heatmap(
ds,
EXPERIMENT_ID,
antenna_positions=antenna_positions,
max_cycle_values=HEATMAP_MAX_CYCLE_VALUES,
)
plt.show()
csi.plot_amplitude_heatmap(
ds,
EXPERIMENT_ID,
antenna_positions=antenna_positions,
max_cycle_values=HEATMAP_MAX_CYCLE_VALUES,
)
plt.show()
