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Summary

Description
English: Power Spectral Densities of the MSK and GMSK. Edit this at Structured Data on Commons
Date
Source Own work
Author Kirlf
PNG development
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This plot was created with Matplotlib.
Source code
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Python code

import numpy as np
import matplotlib.pyplot as plt

def normal(x):
    for idx, item in enumerate(x):
        if item < -100:
            x[idx] = None
    return x

f = np.array([i for i in range(-300, 300, 1)])/100
msk  = (16 / (np.pi**2) )\
                  * (np.cos(6.2832 * f))**2 / (1 - 16 * f**2)**2

BT = [0.3, 0.5]
gmsk = []

for W in BT:
    H_G = np.exp((np.log(2)/(-2.))*(f/W)**2)
    gmsk.append(normal(10*np.log10(msk*H_G)))

msk = normal(10*np.log10(msk))

plt.figure(figsize=(7, 4), dpi=300)
plt.plot(f, msk, label='MSK', color='green')
plt.plot(f, gmsk[1], label='GMSK BT = 0.5', color='red')
plt.plot(f, gmsk[0], label='GMSK BT = 0.3', color='black')
plt.title("Normalized Power Spectral Density")
plt.xlabel('Frequency Offset / Bit Rate (Hz/bit/s)')
plt.ylabel('Spectral Power Level (dB)')
plt.legend()
plt.grid()
plt.savefig('PSD.png')

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w:en:Creative Commons
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  • to share – to copy, distribute and transmit the work
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Under the following conditions:
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  • share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.

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Power Spectral Densities of the MSK and GMSK.

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7 February 2019

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Date/TimeThumbnailDimensionsUserComment
current13:02, 7 February 2019Thumbnail for version as of 13:02, 7 February 20192,100 × 1,200 (219 KB)KirlfUser created page with UploadWizard

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