75 lines
1.7 KiB
Python
75 lines
1.7 KiB
Python
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import numpy as np
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from scipy.special import erf
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def flattop(A, edge, length, fsn):
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'''
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生成平顶包络函数 (Python版本)
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Parameters:
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-----------
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A : float
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幅度
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edge : float
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边沿时间参数
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length : int
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长度（采样点数）
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fsn : float
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采样频率
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Returns:
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--------
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numpy.ndarray
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平顶包络波形
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'''
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Ts = 0
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r_sigma = 0.21230
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T = length / fsn
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t = np.arange(0, length + 2) / fsn
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mu = 0.5 * edge
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sigma = r_sigma * (edge - 1)
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p = T - 1 - edge
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x1 = (t - mu - Ts) / (np.sqrt(2) * sigma)
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x2 = (t - mu - p + Ts) / (np.sqrt(2) * sigma)
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f = A / 2 * (erf(x1) - erf(x2))
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# f_padded = np.pad(f, (1, 1), mode='constant', constant_values=0)
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return f
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"""
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# 使用示例
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if __name__ == "__main__":
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# 测试参数
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A = 1.0 # 幅度
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edge = 0.1 # 边沿时间
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length = 1000 # 长度
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fsn = 10000 # 采样频率
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# 生成平顶包络
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envelope = flattop(A, edge, length, fsn)
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print(f"生成的包络长度: {len(envelope)}")
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print(f"最大值: {np.max(envelope):.6f}")
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print(f"最小值: {np.min(envelope):.6f}")
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# 可选：绘图显示
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try:
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import matplotlib.pyplot as plt
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plt.figure(figsize=(10, 6))
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time_axis = np.arange(len(envelope)) / fsn
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plt.plot(time_axis, envelope, 'b-', linewidth=2)
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plt.xlabel('时间 (s)')
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plt.ylabel('幅度')
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plt.title('平顶包络波形')
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plt.grid(True, alpha=0.3)
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plt.tight_layout()
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plt.show()
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except ImportError:
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print("matplotlib 未安装，跳过绘图")
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"""
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