弹载接收机需同时应对高动态和低信噪比的压力,文中结合北斗二代导航系统特殊的电文体制,提出基于扩展卡尔曼滤波的载波跟踪算法,使弹载北斗二代接收机同时满足高动态和高灵敏度双重要求。仿真表明,该跟踪方案在加速度25g,加加速度100g/s的高动态环境下,相较于传统的FLL辅助PLL方案,相位跟踪误差缩小到约50%,频率跟踪误差缩小到约75%。另外,在信噪比低至36dB-Hz的弱信号环境,该方案仍能保持稳定跟踪。

The missile-borne receivers have to deal with the pressure of the high dynamic and low signal-to-noise ratio, article combined with special navigation message format of the BD-2 navigation system, proposed BD-2 signal carrier tracking algorithm based on extended Kalman filter(EKF), made the missile-borne receivers meet the dual requirements of high dynamic and high sensitivity. Simulation show that compared to traditional FLL assisted PLL program, the EKF tracking program's phase tracking error is reduced to about 50% and frequency tracking error is reduced to about 75% in the high dynamic environment with acceleration of 25g and jerk of 100g/s. In addition, in weak signal environment with C/NO as low as 36dB-Hz, the program keeps stable tracking.