m-thesis-introduction/simulations/airshower_beacon_simulation/lib/tests/test_beacon_fourier.py

#!/usr/bin/env python3

"""
Test the functions in lib concerning
beacon generation and phase measuring
work correctly together.
"""


import matplotlib.pyplot as plt
import numpy as np

import lib

seed = 12345
dt = 1 # ns
frequency = 45e-3 # GHz
N = 5e2

t = np.arange(0, 10*int(1e3), dt, dtype=float)
rng = np.random.default_rng(seed)

phase_res = np.zeros(int(N))

# Vary both the base time and the phase
t_extra = 0
for i in range(int(N)):

    # Change timebase
    t -= t_extra
    t_extra = (2*rng.uniform(size=1) - 1) *1e3
    t += t_extra

    # Randomly phased beacon
    phase = lib.phase_mod(np.pi*(2*rng.uniform(size=1) -1)) # rad
    beacon = lib.sine_beacon(frequency, t, t0=0, phase=phase)

    if True: # blank part of the beacon
        blank_low, blank_high = 2*int(1e3), 4*int(1e3)
        beacon[blank_low:blank_high] = 0

    measured = lib.find_beacon_in_traces([beacon], t, frequency, frequency_fit=False)

    phase_res[i] = lib.phase_mod(measured[1][0] - phase)

fig, ax = plt.subplots()
ax.set_title("Sine beacon phase determination\nwith random time shifts")
ax.set_xlabel("$\\varphi_{meas} - \\varphi_{true}$ [rad]")
ax.set_ylabel("#")
ax.hist(phase_res, bins='sqrt')
plt.show()