105 lines
1.8 KiB
C
105 lines
1.8 KiB
C
/*
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各类滤波器。
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*/
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#pragma once
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#ifdef __cplusplus
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extern "C" {
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#endif
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#include "user_math.h"
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/* 二阶低通滤波器 */
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typedef struct {
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float cutoff_freq; /* 截止频率 */
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float a1;
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float a2;
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float b0;
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float b1;
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float b2;
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float delay_element_1;
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float delay_element_2;
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} LowPassFilter2p_t;
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/* 带阻滤波器 */
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typedef struct {
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float notch_freq; /* 阻止频率 */
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float bandwidth; /* 带宽 */
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float a1;
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float a2;
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float b0;
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float b1;
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float b2;
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float delay_element_1;
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float delay_element_2;
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} NotchFilter_t;
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/**
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* @brief 初始化滤波器
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*
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* @param f 滤波器
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* @param sample_freq 采样频率
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* @param cutoff_freq 截止频率
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*/
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void LowPassFilter2p_Init(LowPassFilter2p_t *f, float sample_freq,
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float cutoff_freq);
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/**
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* @brief 施加一次滤波计算
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*
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* @param f 滤波器
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* @param sample 采样的值
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* @return float 滤波后的值
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*/
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float LowPassFilter2p_Apply(LowPassFilter2p_t *f, float sample);
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/**
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* @brief 重置滤波器
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*
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* @param f 滤波器
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* @param sample 采样的值
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* @return float 滤波后的值
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*/
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float LowPassFilter2p_Reset(LowPassFilter2p_t *f, float sample);
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/**
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* @brief 初始化滤波器
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*
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* @param f 滤波器
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* @param sample_freq 采样频率
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* @param notch_freq 中心频率
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* @param bandwidth 带宽
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*/
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void NotchFilter_Init(NotchFilter_t *f, float sample_freq, float notch_freq,
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float bandwidth);
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/**
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* @brief 施加一次滤波计算
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*
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* @param f 滤波器
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* @param sample 采样的值
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* @return float 滤波后的值
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*/
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float NotchFilter_Apply(NotchFilter_t *f, float sample);
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/**
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* @brief 重置滤波器
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*
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* @param f 滤波器
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* @param sample 采样的值
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* @return float 滤波后的值
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*/
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float NotchFilter_Reset(NotchFilter_t *f, float sample);
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#ifdef __cplusplus
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}
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#endif
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