A tracking loop based on tightly coupled range and velocity filter equations

A joint range-velocity closed tracking loop, which is based on tightly coupled range and velocity filter is proposed. When the measured velocity value is adopted in the range tracking loop to modify the velocity and acceleration equations from traditional α-β-γ filter, the tracking loop based on tightly coupled range and velocity filter can not only track the range and the velocity simultaneously, but also improve the range tracking accuracy. The experimental results show that the tracking errors about range thermal noise in the proposed loop is lower than those in the traditional loop over 2. 2 dB, when filter parameters satisfy least mean-square error criterion. Moreover, with the increase of the filter parameter, the tracking performance of our schemes are improved accordingly.