// 天线阵列相位测量
typedef struct {
    int antenna_count;     // 天线单元数量
    float reference_phase; // 参考相位
    float phase_array[8];  // 各单元相位
    float amplitude_array[8]; // 各单元幅度
} antenna_array_t;

antenna_array_t measure_antenna_array(void) {
    antenna_array_t array;
    array.antenna_count = 4;
    
    // 测量参考单元
    array.reference_phase = 0.0;  // 参考单元定义为0°
    
    // 依次测量各单元与参考的相位差
    for(int i = 1; i < array.antenna_count; i++) {
        // 切换测量通道
        select_antenna_channel(0, i);  // 参考单元vs第i单元
        delay_ms(10);  // 等待稳定
        
        float phase_voltage = read_phase_voltage();
        float gain_voltage = read_gain_voltage();
        
        array.phase_array[i] = voltage_to_phase(phase_voltage);
        array.amplitude_array[i] = voltage_to_gain_db(gain_voltage);
        
        printf("单元%d: 相位=%.1f°, 幅度=%.1fdB\n", 
               i, array.phase_array[i], array.amplitude_array[i]);
    }
    
    return array;
}

// 锁相环测试
void pll_phase_noise_test(void) {
    // 测量PLL输出与参考时钟的相位差
    printf("PLL相位噪声测试\n");
    
    const int SAMPLE_COUNT = 1000;
    float phase_samples[SAMPLE_COUNT];
    
    // 采集相位数据
    for(int i = 0; i < SAMPLE_COUNT; i++) {
        float phase_voltage = read_phase_voltage();
        phase_samples[i] = voltage_to_phase(phase_voltage);
        delay_ms(1);
    }
    
    // 计算相位抖动
    float mean_phase = calculate_mean(phase_samples, SAMPLE_COUNT);
    float phase_std = calculate_std_dev(phase_samples, SAMPLE_COUNT, mean_phase);
    
    printf("平均相位: %.2f°\n", mean_phase);
    printf("相位抖动: %.3f° RMS\n", phase_std);
}