import radarsimpy
radarsimpy.__version__

'10.0.0'

RCS of a corner reflector

This is example shows how to use RadarSimPy to simulate the RCS of an object based on its 3D model.

---

The corner reflector model is with .stl. It can be imported by using meshio module.

import meshio

import plotly.graph_objs as go
from IPython.display import SVG, display

mesh_data = meshio.read('../models/cr.stl')

fig = go.Figure()

fig.add_trace(go.Mesh3d(x=mesh_data.points[:, 0],
                        y=mesh_data.points[:, 1],
                        z=mesh_data.points[:, 2],
                        i=mesh_data.cells[0].data[:, 0],
                        j=mesh_data.cells[0].data[:, 1],
                        k=mesh_data.cells[0].data[:, 2],
                        intensity=mesh_data.points[:, 2],
                        colorscale='Viridis'
                        ))

# fig.show()
display(SVG(fig.to_image(format='svg', scale=1)))

RCS vs frequency

Define the basic parameters required in ray tracing.

• Observation angle phi (Degree)
• Observation angle theta (Degree)
• Frequency freq (Hz)
• Polarization pol
• Ray density density (number of rays per wavelength)

import time
import numpy as np

from radarsimpy.rt import rcs_sbr

phi = 0
theta = 90
freq = np.arange(1, 79, 1)*1e9
pol = [0, 1, 0]
density = 10

rcs = np.zeros_like(freq)

tic = time.time()
for f_idx, f in enumerate(freq):
    rcs[f_idx] = 10*np.log10(
        rcs_sbr('../models/cr.stl',
                f,
                phi,
                theta,
                pol=pol,
                density=density))
toc = time.time()

print('Exec time :'+str(toc-tic) + 's')

Exec time :13.936949491500854s

fig = go.Figure()

fig.add_trace(go.Scatter(x=freq/1e9, y=rcs))

fig.update_layout(
    # title='RCS vs Frequency',
    template="seaborn",
    yaxis=dict(title='RCS (dBsm)'),
    xaxis=dict(title='Frequency (GHz)', dtick=10),
)

# fig.show()
display(SVG(fig.to_image(format='svg', height=400, width=600)))
# fig.write_image('rcs_vs_freq.svg', height=400, width=600)

RCS vs observation angle

phi = np.arange(-90, 90, 0.5)
theta = 90
freq = 77e9
pol = [0, 0, 1]
density = 1

rcs = np.zeros_like(phi)

tic = time.time()
for phi_idx, phi_ang in enumerate(phi):
    rcs[phi_idx] = 10 * np.log10(
        rcs_sbr('../models/cr.stl',
                freq,
                phi_ang,
                theta,
                pol=pol,
                density=density))
toc = time.time()

print('Exec time :'+str(toc-tic) + 's')

Exec time :36.52792453765869s

fig = go.Figure()

fig.add_trace(go.Scatter(x=phi, y=rcs))

fig.update_layout(
    # title='RCS vs Observation Angle',
    template="seaborn",
    yaxis=dict(title='RCS (dBsm)'),
    xaxis=dict(title='Observation angle (Degree)', dtick=20),
)

# fig.show()
display(SVG(fig.to_image(format='svg', scale=1, height=400, width=600)))
# fig.write_image('rcs_vs_angle.svg', height=400, width=600)