Linear Quadratic Gaussian (LQR) controller and Kalman Filter (KF) both are robust when acting separately, but this property is lost if using them together.

针对数字卫星常用的 7 种通信信号调制方式(QPSK、8PSK、16QAM、32QAM、64QAM、16APSK、32APSK)，对零中心归一化瞬时幅度谱密度最大值、四次方谱、幅度、高阶累积量四种特征参数进行了分析，提出了一种联合特征参数的信号调制识别方法．(Aiming at seven communication signal modulation modes commonly used in digital satellite (QPSK, 8PSK, 16QAM, 32QAM, 64QA