A Python tool for generating synthetic magnetic field (B) signals and their rates of change (dB/dt) to evaluate the effectiveness of magnetic sensor fusion algorithms.

• Features
• Installation
• Usage
• Parameters
• Example
• Sample Plots

• Bumps and Piecewise-Regular Signals: Generate complex magnetic field signals combining exponential trends and Gaussian-like pulses.
• Noise Simulation: Add configurable Gaussian noise to both B and dB/dt signals.
• Offset Biases: Apply customizable offsets to simulate sensor biases or external influences.
• Visualization: Optional plotting of generated signals for easy analysis.
• Modularity: Separate functions for signal generation and plotting for enhanced flexibility.

1. Clone the repository:

   git clone https://github.com/ijwkim/MagneticSensorFusionTestSignal.git
   cd MagneticSensorFusionTestSignal

Import the generate_test_signals function from synthetic_signal.py to create synthetic signals. You can also visualize the signals by using the plot_signals function.

from synthetic_signal import generate_test_signals, plot_signals

# Generate synthetic test signals
signals = generate_test_signals()

# Access the generated signals
time = signals['t']                # Time array in seconds
b_true = signals['b_true']         # True magnetic field signal (T)
b_meas = signals['b_meas']         # Measured magnetic field signal with noise (T)
dBdt_true = signals['dBdt_true']   # True rate of change of magnetic field (T/s)
dBdt_meas = signals['dBdt_meas']   # Measured rate of change with noise and offset (T/s)
offset = signals['offset']         # Applied offset to dB/dt (T/s)
measured_sigma = signals['measured_sigma']               # Noise standard deviation for B
diff_measured_sigma = signals['diff_measured_sigma']       # Noise standard deviation for dB/dt

# Plot the generated signals
plot_signals(t, b_true, b_meas, dBdt_true, dBdt_meas, offset, measured_sigma, diff_measured_sigma)

The generate_test_signals function initializes and returns a dictionary of synthetic signals with the following default parameters:

• sampling_freq (float): Sampling frequency in Hz. Default: 1000 Hz
• duration_hours (int): Duration of the signal in hours. Default: 1 hour
• measured_sigma (float): Standard deviation of noise added to the magnetic field (B). Default: 0.1 T
• diff_measured_sigma (float): Standard deviation of noise added to the rate of change of the magnetic field (dB/dt). Default: 0.02 T/s
• These parameters can be adjusted within the generate_test_signals function as needed.

Here is an example script demonstrating how to generate and plot the synthetic signals:

from signal_generator import generate_test_signals, plot_signals

def main():
    # Generate synthetic test signals
    signals = generate_test_signals()
    
    # Extract signals from the returned dictionary
    t = signals['t']
    b_true = signals['b_true']
    b_meas = signals['b_meas']
    dBdt_true = signals['dBdt_true']
    dBdt_meas = signals['dBdt_meas']
    offset = signals['offset']
    measured_sigma = signals['measured_sigma']
    diff_measured_sigma = signals['diff_measured_sigma']
    
    # Plot the signals
    plot_signals(t, b_true, b_meas, dBdt_true, dBdt_meas, offset, measured_sigma, diff_measured_sigma)

if __name__ == "__main__":
    main()

Run the script:

python signal_generator.py

Below are sample plots generated by the script: