Abstract. Low probability of intercept (LPI)
radars have the property of low power, wide bandwidth, frequency variability or
other design features to make them difficult to be detected or identified by
passive intercept receiver devices such as radio engineering complexes
(RTK). In
the RTK the potential error of time parameters measurement is determined by
fluctuations in the signal fronts. With a small signal to noise ratio, the
separation of the pulse fronts becomes practically impossible. In this
connection, a contradiction arises which is associated with the need to
estimate the time parameters of signals of low-visibility radar with an SNR of
less than 0 dB on the one hand and limitations of existing methods on the other
hand. One
of the possible solutions to this contradiction is the measurement of time
parameters using algorithms for morphological processing of the results of
bilinear time-frequency distributions, for example Choi-Williams distribution.
The
purpose of the research was to provide the possibility of automatic estimation
of signals time parameters in conditions of low SNR (less than 0 dB) using
algorithms for morphological processing of the time-frequency distribution
results.
To
achieve this goal the imitation model of the estimating process of the time
parameters (for example, the pulse duration) was developed. The simulation was
carried out in the Matlab R2016a environment. The
proposed approach for estimating the time parameters of signals under
conditions of low SNR (less than 0 dB) is based on the application wavelet thresholding
and morphological processing in a new subject area. The developed simulation
model allows providing the possibility of automatic estimation of signals time
parameters. This approach can be used to jointly assess the frequency and time
parameters of signals from LPI radars.
Key words:
low probability of intercept
radar, time-frequency distributions, radio
engineering complexes, morphology method.
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