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| class VitalSignsRadarProcessor: """生命体征雷达信号处理器""" def __init__(self): self.fc = 60e9 self.bandwidth = 4e9 self.chirp_duration = 100e-6 self.num_chirps = 256 self.sample_rate = 2e6 self.wavelength = 3e8 / self.fc def process_radar_signal(self, adc_data: np.ndarray) -> Tuple[float, float]: """ 处理雷达信号,提取心率和呼吸率 Args: adc_data: (num_chirps, num_samples) ADC数据 Returns: heart_rate: 心率(bpm) respiration_rate: 呼吸率(bpm) """ range_fft = np.fft.fft(adc_data, axis=1) range_profile = np.abs(range_fft[:, :adc_data.shape[1]//2]) target_bin = self._find_target(range_profile) phase_sequence = np.angle(range_fft[:, target_bin]) unwrapped_phase = np.unwrap(phase_sequence) displacement = unwrapped_phase * self.wavelength / (4 * np.pi) heart_rate, respiration_rate = self._extract_vital_signs(displacement) return heart_rate, respiration_rate def _find_target(self, range_profile: np.ndarray) -> int: """找到目标距离bin""" energy = np.sum(range_profile, axis=0) target_bin = np.argmax(energy) return target_bin def _extract_vital_signs(self, displacement: np.ndarray) -> Tuple[float, float]: """ 从位移序列提取生命体征 Args: displacement: 位移序列 Returns: heart_rate: 心率(bpm) respiration_rate: 呼吸率(bpm) """ n = len(displacement) frame_rate = 10 freq = np.fft.rfftfreq(n, 1/frame_rate) spectrum = np.abs(np.fft.rfft(displacement - np.mean(displacement))) hr_mask = (freq >= 0.8) & (freq <= 2.0) hr_spectrum = spectrum[hr_mask] hr_freq = freq[hr_mask] if len(hr_spectrum) > 0: hr_peak_idx = np.argmax(hr_spectrum) heart_rate = hr_freq[hr_peak_idx] * 60 else: heart_rate = 0 rr_mask = (freq >= 0.15) & (freq <= 0.5) rr_spectrum = spectrum[rr_mask] rr_freq = freq[rr_mask] if len(rr_spectrum) > 0: rr_peak_idx = np.argmax(rr_spectrum) respiration_rate = rr_freq[rr_peak_idx] * 60 else: respiration_rate = 0 return heart_rate, respiration_rate
class RobustVitalSignsExtractor: """复杂环境下的鲁棒生命体征提取""" def __init__(self): self.processor = VitalSignsRadarProcessor() self.hr_bandpass = (0.7, 2.5) self.rr_bandpass = (0.1, 0.6) def extract_with_filtering(self, displacement: np.ndarray) -> Tuple[float, float, float]: """ 带滤波的生命体征提取 Args: displacement: 位移序列 Returns: heart_rate: 心率(bpm) respiration_rate: 呼吸率(bpm) snr: 信噪比 """ hr_signal = self._bandpass_filter(displacement, self.hr_bandpass[0], self.hr_bandpass[1]) rr_signal = self._bandpass_filter(displacement, self.rr_bandpass[0], self.rr_bandpass[1]) heart_rate = self._find_peak_frequency(hr_signal) * 60 respiration_rate = self._find_peak_frequency(rr_signal) * 60 snr = self._calculate_snr(hr_signal) return heart_rate, respiration_rate, snr def _bandpass_filter(self, signal: np.ndarray, low_freq: float, high_freq: float) -> np.ndarray: """带通滤波""" from scipy.signal import butter, filtfilt fs = 10 nyq = 0.5 * fs low = low_freq / nyq high = high_freq / nyq low = max(0.001, min(low, 0.99)) high = max(low + 0.001, min(high, 0.99)) b, a = butter(4, [low, high], btype='band') try: filtered = filtfilt(b, a, signal) except: filtered = signal return filtered def _find_peak_frequency(self, signal: np.ndarray) -> float: """找峰值频率""" n = len(signal) freq = np.fft.rfftfreq(n, 0.1) spectrum = np.abs(np.fft.rfft(signal)) if len(spectrum) > 1: peak_idx = np.argmax(spectrum[1:]) + 1 return freq[peak_idx] return 0 def _calculate_snr(self, signal: np.ndarray) -> float: """计算信噪比""" signal_power = np.var(signal) noise = signal - self._bandpass_filter(signal, 0.5, 2.0) noise_power = np.var(noise) if noise_power > 0: snr = 10 * np.log10(signal_power / noise_power) else: snr = 100 return snr
class MultiTargetVitalSigns: """多目标生命体征提取""" def __init__(self): self.processor = VitalSignsRadarProcessor() def separate_targets(self, adc_data: np.ndarray, num_targets: int = 3) -> List[Dict]: """ 分离多个目标的生命体征 Args: adc_data: (num_chirps, num_samples) ADC数据 num_targets: 最大目标数 Returns: vital_signs_list: 各目标生命体征列表 """ range_fft = np.fft.fft(adc_data, axis=1) range_profile = np.abs(range_fft[:, :adc_data.shape[1]//2]) target_bins = self._detect_targets(range_profile, num_targets) vital_signs_list = [] for target_bin in target_bins: phase_sequence = np.angle(range_fft[:, target_bin]) unwrapped_phase = np.unwrap(phase_sequence) displacement = unwrapped_phase * self.processor.wavelength / (4 * np.pi) heart_rate, respiration_rate = self.processor._extract_vital_signs(displacement) distance = target_bin * (3e8 / (2 * self.processor.bandwidth)) vital_signs_list.append({ 'distance': distance, 'heart_rate': heart_rate, 'respiration_rate': respiration_rate, 'signal_strength': np.mean(range_profile[:, target_bin]) }) return vital_signs_list def _detect_targets(self, range_profile: np.ndarray, max_targets: int) -> List[int]: """检测目标""" energy = np.sum(range_profile, axis=0) sorted_indices = np.argsort(energy)[::-1] target_bins = [] for idx in sorted_indices: if len(target_bins) >= max_targets: break valid = True for existing_bin in target_bins: if abs(idx - existing_bin) < 5: valid = False break if valid: target_bins.append(idx) return target_bins
if __name__ == "__main__": processor = VitalSignsRadarProcessor() robust_extractor = RobustVitalSignsExtractor() multi_target = MultiTargetVitalSigns() num_chirps = 256 num_samples = 512 adc_data = np.random.randn(num_chirps, num_samples) * 0.01 for i in range(num_chirps): heart_phase = 2 * np.pi * 1.2 * i / num_chirps * 10 resp_phase = 2 * np.pi * 0.25 * i / num_chirps * 10 phase = heart_phase + resp_phase * 10 target_bin = 100 adc_data[i, target_bin] += np.exp(1j * phase) hr, rr = processor.process_radar_signal(adc_data) print(f"心率: {hr:.1f} bpm") print(f"呼吸率: {rr:.1f} bpm") vitals_list = multi_target.separate_targets(adc_data, num_targets=3) print(f"\n检测到 {len(vitals_list)} 个目标:") for i, vitals in enumerate(vitals_list): print(f" 目标{i+1}: 距离 {vitals['distance']:.2f}m, 心率 {vitals['heart_rate']:.1f} bpm, 呼吸率 {vitals['respiration_rate']:.1f} bpm")
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