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Introduction/purpose: This paper presents a model of a high speed target radar tracking system that is much simpler than the existing ones. The Doppler shift is compensated before signal compression, simultaneously with the modification of the clock signal in the compression filter. This is possible thanks to the development of FPGA technology. The most important for this application are very fast clock control units which enable operation with different frequency references up to 1 GHz with an accuracy far below 1 Hz. Methods: In this paper, the methodology of mathematical modeling and simulation is used. Results: The results of the analysis of the most important effects in radars caused by high-speed targets are presented and discussed - target migration through resolution cells and compression filter response distortion due to high target acceleration. Conclusion: Thanks to flexible RF and signal processing hardware, complex radar processing procedures are not required. The sensitivity of the BPSK signal to the Doppler shift (which is usually considered a disadvantage) can be used to reject targets at a slightly different rate. This system can be used in space debris tracking, airspace target tracking, car driving, etc. [ABSTRACT FROM AUTHOR]

Tracking sinusoidal references with high precision and rejection of sinusoidal disturbances is a challenging task in the motion control practice. In order to deal with this control problem, a new resonant extended state observer is proposed and introduced in the active disturbance rejection control concept. The frequency analysis shows that an appropriate selection of resonant frequency provides complete rejection of sinusoidal disturbance and ideal reference tracking in the steady state. Further, it is shown that the proposed structure achieves better performances than generalised extended state observer based system in the wide frequency range. Moreover, in order to improve the system performances in transient period, the optimal parameter tuning method is developed. The results demonstrate that the optimally tuned system achieves better performances than the conventionally tuned one by about 25%, with the same robustness and noise sensitivity. The experimental validation of the new controller is carried out on the laboratory model of the didactic three-axis radar platform in fast sinusoidal reference tracking mode. [ABSTRACT FROM AUTHOR]