Підвищення точності розрахунку ординат АКФ сигналу розсіяння

Abstract

The result of the simulation of two components of the autocorrelation function (ACF), which reflect the statistical characteristics of incoherent scattering, which are calculated using the main (cosine) and orthogonal (sine) channels of the radar correlation processing system, is given. The algorithm for computing the ACF is demonstrated when the equipment is involved, where there are two parallelly operating orthogonal channels with their own independent amplifying elements. It is shown that there are different options for synchronizing parallel orthogonal channels. In the first of them, the input signal in one of the channels is delayed by a quarter of the intermediate frequency period, and in the other, various series of ADC clocking are used. In these series, the positions of the pulses differ, namely, they are delayed with respect to each other by a quarter of the signal period at the intermediate frequency. It is proposed to reduce the errors that arise as a result of non-identical technical characteristics of these two quadrature signal processing channels. A new structural diagram of the multichannel correlator is considered, which simultaneously calculates both the cosine and the sine components of the autocorrelation function of the scattering signal. The signal comes to it only through one receiver channel and one ADC. It is also proposed to increase the frequency of signal conversion to digital form in order to achieve a much higher density of the ordinates of the autocorrelation function along the delay scale. As a result, the results of the calculation of the parameters of the ionospheric plasma, determined by the form of the ACF, will also have an increased statistical accuracy of the calculations. For the proposed option to obtain quadrature components of the ACF, a modified expression has been proposed for calculating the values of the radial velocity of the ionospheric plasma.