Yu.L. Koziratsky, A.V. Ivantsov, N.N. Tolstyh, V.M. Kildjushevsky
Nowadays a wide usage have received radars, based on chirp waveform, solving a wide range of tasks. The most effective way to deteriorate effectiveness of detection and localization of objects by such radars is imitation of reflected signals.
While generating interferences it is necessary to evaluate the variation of intrapulse frequency of chirp waveform.
For this purpose transformation of frequency to a voltage by means of the converter with a linearly-accruing amplitude-frequency response is made. However in practice it is impossible to achieve ideally direct gain-frequency variation. For that purpose the devices, providing linearity of gain-frequency variation with some error are used.
The corresponding methodical apparatus is necessary for an estimation of admissible values of an error of reproduction chirp signal at influence of hindrances. For the task in view decision the estimated signal has been presented in a kind to sample of supervisions and frequency rates during each moment of a capture of samples for initial spectral amplitudes, and then corresponding values of observable samples of a signal after transformation taking into account non-linearity spectral amplitudes are defined. With use of a joint density function of probabilities of a vector of initial supervisions the effective estimation of initial frequency and a signal slope has been presented in the form of a linear combination of corresponding components of full sufficient statistics. The algorithm of an estimation of parametres of the chirp signal is offered, allowing to define initial frequency and a slope of a signal taking into account non-linearity spectral amplitudes of the converter and to estimate accuracy of these parametres of shaping of an imitating hindrance as a part of the combined false targets.