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Amplitude factor corrected

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Jan Käberich 2020-09-17 09:54:21 +02:00
parent 00244022c9
commit 76875c2316
3 changed files with 27 additions and 17 deletions
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16
FPGA/WindowCoefficientGenerator.py
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@ -22,6 +22,8 @@ class Window:
self.name = name
self.function = function
self.correction = correction
self.sum = 0
self.num_coeff = 0
def StartFile(self):
self.file = open(self.name+".dat", "w")
@ -30,6 +32,8 @@ class Window:
if not hasattr(self, 'file'):
self.StartFile()
value = self.function(normalized_index)
self.sum = self.sum + value
self.num_coeff = self.num_coeff + 1
if INCLUDE_AMPLITUDE_CORRECTION:
value = value * self.correction / 8.0
value = int(value * (2 ** (BITS_PER_COEFFICIENT-1)))
@ -39,6 +43,9 @@ class Window:
output = bindigits(value, BITS_PER_COEFFICIENT)
self.file.write(output+"\n")
def CorrectionFactor(self):
return 1.0 / (self.sum / self.num_coeff)
def calc_hann(i):
return math.sin(math.pi * i) ** 2
@ -54,12 +61,15 @@ def calc_flattop(i):
return a0 - a1 * math.cos(2*math.pi*i) + a2 * math.cos(4*math.pi*i) - a3 * math.cos(6*math.pi*i) + a4 * math.cos(8*math.pi*i)
WindowList = []
WindowList.append(Window("Hann", calc_hann, 2.0))
WindowList.append(Window("Kaiser", calc_kaiser, 2.49))
WindowList.append(Window("Flattop", calc_flattop, 4.18))
WindowList.append(Window("Hann", calc_hann, 2.00))
WindowList.append(Window("Kaiser", calc_kaiser, 2.50))
WindowList.append(Window("Flattop", calc_flattop, 4.64))
for i in range(NUMBER_OF_COEFFICIENTS):
norm_i = (i+0.5) / NUMBER_OF_COEFFICIENTS
for w in WindowList:
w.AddCoefficient(norm_i)
for w in WindowList:
print(w.CorrectionFactor())