The Algorithm for Deep-Space Weak Signal Tracking Using a Modified Kalman Filter

In Deep-space TT&C and communication, the received signal is very weak, so the traditional Kalman Filter is hard to track the signal accurately. In this paper, a modified Kaman Filter using least squares (LS) method is presented to address this issue. This method is good at tracking amplitude, phase, frequency and its time derivatives of frequency (the signal with low carrier acquisition threshold and high dynamic). Computer simulation shows that the lower carrier power -157dBm can be achieved with this method.