A joint estimation method of sky-wave over-the-horizon radar target and ionospheric parameters

Abstract

The invention discloses a sky-wave over-the-horizon radar target and ionospheric parameter joint estimation method, which belongs to the technical field of radar. The invention sets the parameter to be estimated as the joint parameter of the target and the ionosphere, uses an analytical model to convert the error of the ionosphere detection equipment into an estimation error of the target parameter, corrects the estimated parameter, and realizes joint estimation of the ionosphere and the target parameter. The invention solves the problem that the ionospheric parameter error estimation cannot be combined in the existing estimation method, enables the ionospheric error information to be effectively used, and improves the estimation accuracy.

Description

technical field [0001] The invention belongs to the field of radar technology, and in particular relates to an algorithm for jointly estimating sky-wave over-the-horizon radar target parameters by using ionospheric information. Background technique [0002] OTHR (Over-the-horizon radar) uses high-frequency electromagnetic waves of 3-30MHz to propagate from top to bottom after ionospheric reflection. It can realize large-area and ultra-long-distance target detection, and has important tactical and strategic value. In the current OTHR research, the estimation of target parameters is the fundamental purpose of OTHR engineering application, so the accurate estimation of target parameters is of great significance. Due to the special working mode of OTHR, the study of ionosphere is very important. The ionospheric parameters are obtained by the inversion of the ionospheric detection equipment, which has a large measurement error. In similar algorithms, the ionospheric parameters ...

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Problems solved by technology

The ionospheric parameters are obtained by the inversion of the ionospheric detection equipment, which has a large measurement error. In similar algorithms, the ionospheric parameters are regarded as unbiased information, ignoring the error of the detection equipment, and the estimated target parameters are all not precise enough

[0003] The existing sky-wave radar maneuvering target parameter estimation algorithms mainly fall into two categories: the first is the maneuvering target detection method based on time-frequency analysis, such as the adaptive wavelet transform algorithm (Wang G, Xia X G, Root B T, et al. Movingtarget detection in over-the-horizon radar using adaptive chirplet transform[J].Radio Science,2002,38(4):77-84.) and Wigner-Ville decomposition method (Frazer G J,AndersonS J.Wigner-Ville analysis of HF radar measurement of an accelerating target[C]International Symposium on Signal Processing and ITS Applications.1999:317-320vol.1.), but when there are multiple maneuvering targets, this type of method will be interfered by the cross term

The second category is the maneuvering target detection algorithm based on polynomial phase modeling, such as the maneuvering target compensation method based on the high-order ambiguity function (HAF) (LuK, Liu X. Enhanced visibility of maneuvering targets for high-frequency over-the-horizon radar [J].IEEE Transactions on Antennas&Propagation,2005,53(1):404-411.), this method solves the coefficients of each order of the polynomial through the high-order fuzzy function to estimate the parameters of the maneuvering target, which has the advantage of low calculation amount, but this method The method requires a high input signal-to-noise ratio when solving the high-order coefficients of polynomials, and there is an obvious error accumulation effect

The other is a maneuvering target detection algorithm based on Cubic Phase Function (CPF) (O'Shea P.A new technique for instantaneous frequency rate estimation [J]. IEEE Signal Processing Letters, 2002, 9(8): 251-252 .), the algorithm avoids the multiple use of nonlinear transformation and reduces the SNR loss, but the estimation accuracy is not high

[0004] In engineering practice, the measurement error of ionospheric detection equipment seriously affects the target parameter estimation accuracy of sky-wave over-the-horizon radar, and all current maneuvering target parameter estimation algorithms do not consider the influence of ionospheric detection equipment error

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