.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "auto_examples/plot_1_3_3_transient.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        Click :ref:`here <sphx_glr_download_auto_examples_plot_1_3_3_transient.py>`
        to download the full example code

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_auto_examples_plot_1_3_3_transient.py:


====================================
Spectrum of a Noisy Transient Signal
====================================

This example shows how to generate a noisy transient signal with the following
characteristics:

    * One-sided exponential amplitude modulation (See :ref:`amexpos`)
    * Constant frequency modulation (See :ref:`fmconst`)
    * -5 dB complex gaussian noise (See :ref:`noisecg` and :ref:`sigmerge`)

And how to plot its energy spectrum.

Figure 1.10 of the tutorial.

.. GENERATED FROM PYTHON SOURCE LINES 25-55



.. image-sg:: /auto_examples/images/sphx_glr_plot_1_3_3_transient_001.png
   :alt: Noisy Transient Signal, Energy spectrum of noisy transient signal
   :srcset: /auto_examples/images/sphx_glr_plot_1_3_3_transient_001.png
   :class: sphx-glr-single-img





.. code-block:: default



    import numpy as np
    import matplotlib.pyplot as plt
    from tftb.generators import amexpos, fmconst, sigmerge, noisecg

    # Generate a noisy transient signal.
    transsig = amexpos(64, kind='unilateral') * fmconst(64)[0]
    signal = np.hstack((np.zeros((100,)), transsig, np.zeros((92,))))
    signal = sigmerge(signal, noisecg(256), -5)
    fig, ax = plt.subplots(2, 1)
    ax1, ax2 = ax
    ax1.plot(np.real(signal))
    ax1.grid()
    ax1.set_title('Noisy Transient Signal')
    ax1.set_xlabel('Time')
    ax1.set_xlim((0, 256))
    ax1.set_ylim((np.real(signal).max(), np.real(signal.min())))

    # Energy spectrum of the signal
    dsp = np.fft.fftshift(np.abs(np.fft.fft(signal)) ** 2)
    ax2.plot(np.arange(-128, 128, dtype=float) / 256, dsp)
    ax2.set_title('Energy spectrum of noisy transient signal')
    ax2.set_xlabel('Normalized frequency')
    ax2.grid()
    ax2.set_xlim(-0.5, 0.5)

    plt.subplots_adjust(hspace=0.5)

    plt.show()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** ( 0 minutes  0.169 seconds)


.. _sphx_glr_download_auto_examples_plot_1_3_3_transient.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example


    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: plot_1_3_3_transient.py <plot_1_3_3_transient.py>`

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: plot_1_3_3_transient.ipynb <plot_1_3_3_transient.ipynb>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_