1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306
| """ CPD检测算法完整实现 基于TI AWRL6432雷达数据流
核心步骤: 1. ADC数据采集 → 2. 距离/多普勒FFT → 3. CFAR检测 → 4. 生命体征提取 → 5. 神经网络分类 """
import numpy as np from typing import Tuple, List, Optional from dataclasses import dataclass from scipy import signal import onnxruntime as ort
@dataclass class DetectedTarget: """检测到的目标""" range_idx: int doppler_idx: int snr: float x: float y: float velocity: float is_living: bool confidence: float
class CPDAlgorithm: """儿童遗留检测算法""" def __init__(self, config_path: str = "cpd_model.onnx"): """ 初始化CPD检测算法 Args: config_path: ONNX模型路径(边缘AI模型) """ self.freq_center = 60e9 self.freq_slope = 70e12 self.num_samples = 256 self.num_chirps = 128 self.sample_rate = 10e6 self.c = 3e8 self.range_fft_size = 256 self.doppler_fft_size = 128 self.cfar_guard_cells = 4 self.cfar_train_cells = 16 self.cfar_threshold = 2.5 try: self.session = ort.InferenceSession(config_path) self.input_name = self.session.get_inputs()[0].name self.output_name = self.session.get_outputs()[0].name except Exception as e: print(f"警告:无法加载ONNX模型,使用规则引擎:{e}") self.session = None def range_fft_processing(self, adc_data: np.ndarray) -> np.ndarray: """ 距离FFT处理 Args: adc_data: 原始ADC数据 (num_chirps, num_rx, num_samples) Returns: range_fft: 距离-数据矩阵 (num_chirps, num_range_bins) """ range_fft = np.fft.fft(adc_data, n=self.range_fft_size, axis=-1) range_fft = np.abs(range_fft) / self.num_samples return range_fft.mean(axis=1) def doppler_fft_processing(self, range_fft: np.ndarray) -> np.ndarray: """ 多普勒FFT处理(检测微动) Args: range_fft: 距离FFT结果 (num_chirps, num_range_bins) Returns: range_doppler_map: 距离-多普勒图 (num_doppler_bins, num_range_bins) """ doppler_fft = np.fft.fftshift( np.fft.fft(range_fft, n=self.doppler_fft_size, axis=0), axes=0 ) return np.abs(doppler_fft) def cfar_detection( self, range_doppler: np.ndarray, threshold: float = 2.5 ) -> List[Tuple[int, int, float]]: """ CA-CFAR检测算法 Args: range_doppler: 距离-多普勒图 threshold: 检测阈值(dB) Returns: detections: [(range_idx, doppler_idx, snr), ...] """ detections = [] num_doppler, num_range = range_doppler.shape for dr in range(self.cfar_guard_cells + self.cfar_train_cells, num_range - self.cfar_guard_cells - self.cfar_train_cells): for dd in range(self.cfar_guard_cells + self.cfar_train_cells, num_doppler - self.cfar_guard_cells - self.cfar_train_cells): guard_start_r = dr - self.cfar_guard_cells guard_end_r = dr + self.cfar_guard_cells + 1 train_start_r = dr - self.cfar_guard_cells - self.cfar_train_cells train_end_r = dr + self.cfar_guard_cells + self.cfar_train_cells + 1 train_region = np.concatenate([ range_doppler[train_start_r:guard_start_r, :], range_doppler[guard_end_r:train_end_r, :] ]) noise_level = np.mean(train_region) test_value = range_doppler[dd, dr] detection_threshold = noise_level * threshold if test_value > detection_threshold: snr = 10 * np.log10(test_value / noise_level) detections.append((dr, dd, snr)) return detections def estimate_vital_signs( self, adc_data: np.ndarray, target_range: int ) -> Tuple[float, float]: """ 估计生命体征(呼吸率、心率) Args: adc_data: 原始ADC数据 target_range: 目标距离索引 Returns: breathing_rate: 呼吸频率 (breaths/min) heart_rate: 心率 (beats/min) """ range_fft = np.fft.fft(adc_data, n=self.range_fft_size, axis=-1) phase_sequence = np.angle(range_fft[:, 0, target_range]) phase_unwrapped = np.unwrap(phase_sequence) fs = self.num_chirps * 10 nyquist = fs / 2 b_breath, a_breath = signal.butter(2, [0.1/nyquist, 0.5/nyquist], btype='band') breathing_signal = signal.filtfilt(b_breath, a_breath, phase_unwrapped) b_heart, a_heart = signal.butter(2, [0.8/nyquist, 2.0/nyquist], btype='band') heart_signal = signal.filtfilt(b_heart, a_heart, phase_unwrapped) def extract_frequency(sig, fs): fft_result = np.abs(np.fft.rfft(sig)) freqs = np.fft.rfftfreq(len(sig), 1/fs) peak_idx = np.argmax(fft_result[1:]) + 1 return freqs[peak_idx] * 60 breathing_rate = extract_frequency(breathing_signal, fs) heart_rate = extract_frequency(heart_signal, fs) return breathing_rate, heart_rate def classify_target( self, range_doppler: np.ndarray, vital_features: np.ndarray ) -> Tuple[bool, float]: """ 分类目标类型(儿童/成人/宠物/物体) Args: range_doppler: 距离-多普勒特征 vital_features: 生命体征特征 [breathing_rate, heart_rate, energy] Returns: is_child: 是否为儿童 confidence: 置信度 """ if self.session is None: breathing_rate, heart_rate = vital_features[:2] is_child = (20 < breathing_rate < 40) and (80 < heart_rate < 120) confidence = 0.7 if is_child else 0.3 return is_child, confidence input_features = np.concatenate([ range_doppler.flatten()[:1024], vital_features ]).astype(np.float32) input_features = input_features.reshape(1, -1) outputs = self.session.run( [self.output_name], {self.input_name: input_features} ) probabilities = outputs[0][0] is_child = probabilities[0] > 0.5 confidence = probabilities[0] if is_child else max(probabilities) return is_child, confidence def process_frame(self, adc_data: np.ndarray) -> List[DetectedTarget]: """ 处理单帧雷达数据 Args: adc_data: ADC原始数据 (num_chirps, num_rx, num_samples) Returns: targets: 检测到的目标列表 """ range_fft = self.range_fft_processing(adc_data) range_doppler = self.doppler_fft_processing(range_fft) detections = self.cfar_detection(range_doppler) targets = [] for range_idx, doppler_idx, snr in detections: range_m = range_idx * self.c / (2 * self.freq_slope * self.num_samples / self.sample_rate) breathing_rate, heart_rate = self.estimate_vital_signs(adc_data, range_idx) vital_features = np.array([breathing_rate, heart_rate, snr]) is_child, confidence = self.classify_target(range_doppler, vital_features) target = DetectedTarget( range_idx=range_idx, doppler_idx=doppler_idx, snr=snr, x=range_m * np.cos(np.pi / 4), y=range_m * np.sin(np.pi / 4), velocity=doppler_idx * 0.1, is_living=(breathing_rate > 0), confidence=confidence ) targets.append(target) return targets
if __name__ == "__main__": np.random.seed(42) adc_data = np.random.randn(128, 2, 256) * 0.05 t = np.linspace(0, 12.8, 128) breathing = 0.3 * np.sin(2 * np.pi * 0.42 * t) for i in range(2): adc_data[:, i, 80] += breathing detector = CPDAlgorithm() targets = detector.process_frame(adc_data) print(f"\n检测到 {len(targets)} 个目标:") for i, target in enumerate(targets): print(f"目标 {i+1}:") print(f" 距离: {target.x:.2f}m") print(f" 是否为生命体: {target.is_living}") print(f" 置信度: {target.confidence:.2%}")
|