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        "value": "The Sentinel-1A/B Instrument Processing Facility uses generalized Hamming\nwindows in the processing of spaceborne Synthetic Aperture Radar (SAR)\ndata [3]_. The facility uses various values for the :math:`\\alpha`\nparameter based on operating mode of the SAR instrument. Some common\n:math:`\\alpha` values include 0.75, 0.7 and 0.52 [4]_. As an example, we\nplot these different windows.\n\n"
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        "value": "import numpy as np\nfrom scipy.signal.windows import general_hamming\nfrom scipy.fft import fft, fftshift\nimport matplotlib.pyplot as plt\n",
        "execution_status": "success",
        "out": ""
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        "value": "spatial_plot.set_title(\"Generalized Hamming Windows\")\nspatial_plot.set_ylabel(\"Amplitude\")\nspatial_plot.set_xlabel(\"Sample\")\n",
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        "value": "freq_plot.set_title(\"Frequency Responses\")\nfreq_plot.set_ylabel(\"Normalized magnitude [dB]\")\nfreq_plot.set_xlabel(\"Normalized frequency [cycles per sample]\")\n",
        "execution_status": "failure",
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        "value": "for alpha in [0.75, 0.7, 0.52]:\n    window = general_hamming(41, alpha)\n    spatial_plot.plot(window, label=\"{:.2f}\".format(alpha))\n    A = fft(window, 2048) / (len(window)/2.0)\n    freq = np.linspace(-0.5, 0.5, len(A))\n    response = 20 * np.log10(np.abs(fftshift(A / abs(A).max())))\n    freq_plot.plot(freq, response, label=\"{:.2f}\".format(alpha))\nfreq_plot.legend(loc=\"upper right\")\nspatial_plot.legend(loc=\"upper right\")\n",
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  "references": [
    ".. [1] DSPRelated, \"Generalized Hamming Window Family\",",
    "       https://www.dsprelated.com/freebooks/sasp/Generalized_Hamming_Window_Family.html",
    ".. [2] Wikipedia, \"Window function\",",
    "       https://en.wikipedia.org/wiki/Window_function",
    ".. [3] Riccardo Piantanida ESA, \"Sentinel-1 Level 1 Detailed Algorithm",
    "       Definition\",",
    "       https://sentinel.esa.int/documents/247904/1877131/Sentinel-1-Level-1-Detailed-Algorithm-Definition",
    ".. [4] Matthieu Bourbigot ESA, \"Sentinel-1 Product Definition\",",
    "       https://sentinel.esa.int/documents/247904/1877131/Sentinel-1-Product-Definition"
  ],
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