Frequency swept signals

Date:2011-05-19 (last modified), 2010-06-19 (created)

This page demonstrates two functions in scipy.signal for generating frequency-swept signals: `chirp` and `sweep_poly`.

Some of these require SciPy 0.8.

To run the code samples, you will need the following imports:

In [1]:
import numpy as np
from scipy.signal import chirp, sweep_poly

Linear Chirp

Sample code:

In [3]:
t = np.linspace(0, 10, 5001)
w = chirp(t, f0=12.5, f1=2.5, t1=10, method='linear')

Quadratic Chirp

Sample code:

In [4]:
t = np.linspace(0, 10, 5001)
w = chirp(t, f0=12.5, f1=2.5, t1=10, method='quadratic')

Sample code using `vertex_zero`:

In [5]:
t = np.linspace(0, 10, 5001)
w = chirp(t, f0=12.5, f1=2.5, t1=10, method='quadratic', vertex_zero=False)

Logarithmic Chirp

Sample code:

In [6]:
t = np.linspace(0, 10, 5001)
w = chirp(t, f0=12.5, f1=2.5, t1=10, method='logarithmic')

Hyperbolic Chirp

Sample code:

In [7]:
t = np.linspace(0, 10, 5001)
w = chirp(t, f0=12.5, f1=2.5, t1=10, method='hyperbolic')

Sweep Poly

Sample code:

In [9]:
p = np.poly1d([0.05, -0.75, 2.5, 5.0])
t = np.linspace(0, 10, 5001)
w = sweep_poly(t, p)

The script that generated the plots is here

Section author: WarrenWeckesser

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