RU2786622C1 - Method for adequately determining the current intervals of relative stationarity of ionospheric-spatial propagation of radio waves - Google Patents

Abstract

FIELD: radar systems.

SUBSTANCE: invention is intended to solve the problems of adaptation of over-the-horizon radar systems (OHRS) to stochastic heliogeophysical conditions of the ionosphere by transferring the inverse and incorrect problem of estimating its stationarity using back-and-forth sounding (BFS) of OHRS traces into the correctness class. In the proposed method, a cyclic reciprocal-slope probing of the SGR lines with a period T_δ is carried out with two signals displayed approximately by the Dirac δ-functions: a quasi-monochromatic "on" signal and a short strobe pulse. Next, a standard radio reception is carried out, the received signals

are switched to the inputs of the node for assessing the relative stationarity (RS) of the ionospheric-spatial propagation of radio waves and their subsequent processing, taking into account the location delay. During processing in each cycle, the parameters of the signals

are analyzed separately by frequency and delay, the calculation in the metric L2 of indicators of critical relative changes from cycle to cycle of the characteristics of the received signals

. On this basis, decisions are made about a critical threshold relative change or maintaining the stationarity of the ISPRW in frequency and delay in the mentioned interval. As a result, the duration of a continuous interval of relative stationarity is determined as the sum of periods T_δ going without interruptions, in which the obtained estimate of the current state of relative stationarity of the ISPRW is stored.

EFFECT: ensuring the adaptation of the OH radar to non-stationary conditions of ionospheric-spatial propagation of radio waves (ISPRW) and the possibility of reliable detection of targets and determining the parameters of their movement.

1 cl, 1 dwg

Description

The field of technology.

The invention relates to the field of radio engineering, specifically to methods for determining in real time intervals of stationarity of ionospheric-spatial propagation of radio waves (IPRRV). It can be used in radio sounding, radio direction finding, radio communications, over-the-horizon radar (ZGRL) in the decameter (DKM) radio wave range. It can be mainly used in the systems of ZGRL operating under conditions of a critical impact on the radio reception of the ionosphere, as a non-stationary medium of radio wave propagation (RRW), all kinds of active (AP) and passive interference (PP).

The level of technology.

Currently used in over-the-horizon radars (OZH radars) methods of processing location signals (LCS) - correlation reception (CRP) and matched filtering (GFS) in various modifications - are based on the methods of statistical radio engineering, on assumptions about the stationarity of heliogeophysical conditions (HFC) of propagation radio waves through the ionosphere, the knowledge of the laws of distribution of received signals, on the traditional statistical assessment of their parameters - the average and / or median assessment of the characteristics of regular (stably observed / measured, respectively - relatively long-term) HFC variations in the ionosphere, displayed by various models. These models, as a rule, are corrected according to the data of the analysis of RP - obliquely generated in the process of radar signals of reciprocating-oblique sounding (BIS), the sources of which are a complex of objects / phenomena on the location paths - sources of multiplicative effects ( MP-impacts, MB-interference). Under the location signal - LKS - we will further understand the propagating radar signal at any point of the location route, due to the radiation of the radio transmitter (RPD) of the probing signal (ES), both reflected from the Target, and from the complex of other mentioned objects / phenomena - sources of MP effects [ 1-4]. Stochastic deviations of HFCs from the applied model trends (relatively fast and often very deep) in the general case cannot be reliably determined by the currently used statistical methods due to their inertia [4…6]. The subsystems for adapting the existing MG radars to the variability of HFCs (AHFCs) control their settings, as already mentioned, based on knowledge/measurements of changes in the ionospheric HFCs that are regular over relatively long time intervals, forecasts and estimates of current HFC variations by various methods [2, 3]. Therefore, due to the non-stationarity of the IPRRV, in the general case, the adaptation of the MG radar to the stochastic variability of the HFC is adequate only to special cases according to the operating conditions (OSF) [2-5]. Under the USF of an overhead radar station, we mean the presence of the technical conditions necessary for an overhead radar, the presence of any possible set of Targets on the paths of an overhead radar, stochastic conditions in the general case of the IPRRV through the ionosphere with scattering / reflection of radio waves from its conditional layers, local ionospheric formations with an increased electron density N _EL and from the ground "light / reflection spot" (NPZO) of radio waves, the presence of diverse, generating PP, sources of multiplicative effects (IMV) on the propagating LKS, active interference (AP) (the list is not exhaustive). Quite often, with complex USF, mainly for reasons arising, among other things, from the absence of algorithms for taking into account the non-stationarity of the IPRR in the existing subsystems of the ASFU, there are arbitrarily large losses Δ I ^{2 of} information about the Target contained in the received (useful in this case) signal (PS). That is, either an unacceptable deviation of the estimated parameters of the detected Target from a priori known/reasonably expected ones is fixed up to the statement of the impossibility of detection [1-5]. This is confirmed by the practice of ZGRL [2, 3].

Methods and devices are known that have the task or the ability to solve, to a certain extent, the problems of adequate estimates of HFCs, the non-stationarity of the IPRRP and adaptation to them. Their theoretical foundations and practical applications are described in many works, for example, in [2-5, 8-16, etc.]. However, they are devoted to statistical analysis and modeling of regular HFC macrochanges in the ionosphere by statistical methods on fairly representative samples and do not adequately reflect the radiophysical characteristics (RPC) of the fine stochastic structure and dynamics of the ionosphere, which are the sources of nonstationarity of the IPRRT and, accordingly, instability/erroneousness to a certain extent of current estimates of OFR, angular and other modes of operation of the MG radar [2…5, 9…13, etc.].

Known "Method for determining the intervals of relative stationarity of signals of ionospheric-spatial propagation of radio waves" [RU 2721622], which consists in cyclic with a period of Tδ back-tilt sounding (VHZ / δ D-sounding) of over-the-horizon radar (ZGRL) routes by transmitting a radio transmitter (RPD) in at the beginning of each cycle, before the emission of a standard probing signal (SS), two successively "trial" δ D-signals (BIS / δ D-signals) displayed approximately by the Dirac δ-functions: relatively long quasi-monochromatic signal δ Дƒ "on" with a duration of δ t pr ƒ and a relatively short strobe pulse δ Dτ duration δ tprτ, standard radio reception and processing of the corresponding received "trial" signals and taking into account their location delay.

выполняют с учетом их локационной задержки в виде последовательности следующих действий над сигналами

, а именно, в начале цикла Тδ _i в момент t _прƒ начала сигнала δ_{Д ƒ} «включения» осуществляют измерение совокупности амплитудно-частотных характеристик (АЧХ) {A_i, ƒ_i, σ_i} _ƒ составляющей (

) _i принятых пробных сигналов, обусловленной передачей сигнала δ _{Д ƒ} длительностью δ t _{пр ƒ}, на интервале δ t _{АН ƒ} , где: A_i - амплитуда, ƒ_i - частота и σ_i - спектр i-го сигнала. Затем в момент окончания импульса «включения» и одновременного начала строб-импульса δ_Дτ измеряют АЧХ {A_i, σ _i, τ_3i} составляющей (

) _i , обусловленной передачей сигнала δ_Дτ, длительностью Т_ди на интервале δ t _АН τ = Т_ди с учетом её параметров по задержке. Далее данные измерений используют для генерации представлений соответствующих моделей (

) _i и (

) _i сигналов как функций их частоты и задержки. Затем сигналы моделей (

) _i и (

) _i подвергают задержке на величину Тδ и формируют таким образом их копии (

) _{( i + j )} , (

) _{( i + j )} , которые применяют для вычисления показателей относительной стационарности

и

в виде «невязки» i-х и (i+j)-х представлений указанных моделей в обоих сечениях. Далее сигналы этих показателей используют для выработки по критерию больше/меньше задаваемого порога

частных решений в сечениях ƒ и τ₃ о критичном относительном изменении или сохранении на интервале от i-го до (i+j)-го цикла ВНЗ/δ_Д-зондирования параметров текущего состояния стационарности ионосферно-пространственного распространения радиоволн (ИПРРВ). Затем по критерию совпадения полученных ранее в сечениях ƒ и τ₃ частных решений об изменении или сохранении текущего состояния стационарности принимают окончательное двумерное решение о критичном относительном изменении или сохранении на текущем интервале Тδ от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования текущего состояния стационарности ИПРРВ. Обработку принятых пробных сигналов

завершают суммированием интервалов идущих без перерывов периодов Тδ, в которых сохраняется текущее состояние стационарности для оценки общего непрерывного интервала стационарности δ t _{ст Σ} сигналов загоризонтной радиолокации.In this case, the cyclic BIS/δ_D-probing of radar tracks is implemented by sequential radiation by a radio transmitter (RPD) at the beginning of the cycleT _{δ i} alternately two "trial" δ_D-signals, namely, a quasi-monochromatic “on” signal and a strobe pulse, displayed approximately by the Dirac functions of a quasi-monochromatic “on” signal and a strobe pulse. Processing of received probe signals

are performed taking into account their location delay in the form of a sequence of the following actions on signals

, namely, at the beginning of the cycleTδ _i in the momentt _prƒ the beginning of the signal δ_{D ƒ} "switching on" measure the totality of the amplitude-frequency characteristics (frequency response) {A_i, ƒ_i, σ_i} _ƒ component (

) _i received probe signals due to signal transmission δ _{D ƒ} duration δt _{pr ƒ}, on the interval δt _{AN ƒ} , where: A_i - amplitude, ƒ_i - frequency and σ_i - spectrum of the i-th signal. Then, at the end of the "on" pulse and the simultaneous start of the strobe pulse δ_Dτ is measuredfrequency response {A_i, σ_i, τ_3i} component (

) _i , due to signal transmission δ_Dτ, duration T_di on the interval δt _AN τ = T_di taking into account its delay parameters. Further, the measurement data is used to generate representations of the corresponding models (

) _i and (

) _i signals as functions of their frequency and delay. Then the model signals (

) _i and (

) _i subjected to a delay ofTδ and thus form their copies (

) _{( i + j )} , (

) _{( i + j )} , which are used to calculate the indicators of relative stationarity

and

in the form of a "discrepancy"i-x and (i+j)-x representations of these models in both sections. Further, the signals of these indicators are used to generate the criterion more / less than the specified threshold

partial solutions in sectionsƒ and τ₃ about a critical relative change or preservation in the interval fromi-th to (i+j)-th cycle/δ_D- sounding the parameters of the current state of stationarity of ionospheric-spatial propagation of radio waves (IPRRW). Thenby matching criterion previously obtained in sectionsƒ and τ₃ private decisions about changing or maintaining the current state of stationarity make the final two-dimensional decision on a critical relative change or preservation in the current intervalTδ fromi-th to (i + j)-th cycle/δ_D-probing the current state of stationarity of the IPRRV. Processing of received probe signals

complete by summing the intervals of periods without breaksTδ in which the current stationarity state is stored to estimate the total continuous stationarity interval δt _{st Σ} over-the-horizon radar signals.

The disadvantage of the known method for determining the intervals of relative stationarity of signals of ionospheric-spatial propagation of radio waves” [RU 2721622] is that:

) _i квазимонохроматических «пробных» сигналов

, принятых в начале периода Тδ _i , описана в виде традиционных амплитудно-частотных характеристик (АЧХ) {A _i , ƒ _i , σ_i} _ƒ ;- a set of measured frequency characteristics (

) _i quasi-monochromatic “trial” signals

, taken at the beginning of the period T δ _i , is described in the form of traditional amplitude-frequency characteristics (AFC) {A _i , ƒ _i , σ _i } _ƒ ;

) _i характеристик принятых строб-импульсов также определяют как АЧХ вместо АДХ- амплитудно-дальностных характеристик;- collection (

) _i characteristics of the received strobe pulses are also defined as frequency response instead of ADC-amplitude-range characteristics;

- the final decision on the fundamental change or preservation of the state/stationarity of the IPRR on the location path is made on the basis of partial conclusions on frequency and delay according to the criterion of their COINCIDENCE. This is a fundamental mistake, since, according to the COINCIDENCE criterion, it is really necessary to draw a conclusion only while maintaining both indicators and within the limits of relative stationarity thresholds. That is, with relatively small changes in the parameters of the received "trial" signals from cycle to cycle of BIS/δ D-sounding. Critical superthreshold relative changes in the characteristics of “trial” signals at relatively short periods Тδi, due to the uncertainty in the degree of correlation connectivity of the fluctuation characteristics of the received signals in terms of ƒ and τz, resulting from the stochasticity of the ionosphere, can only be determined by the OR criterion.

Such shortcomings [RU 2721622] lead to inadequate modeling of the received BIS / δ _D -signals in the sections ƒ and τ _s , and inadequate assessment of the numerical values of the intervals of stationarity of signals of ionospheric-spatial propagation of radio waves "and the parameters of the current state of the IPRR.

Statement of the problem of the invention

The objective of the invention is to eliminate the shortcomings of the prototype and increase the degree of adequacy of the assessment of the stationarity intervals of the signals of the ionospheric-spatial propagation of radio waves

The technical result , achieved by solving the problem, is to increase the accuracy of measurements of the current intervals of relative stationarity of the ionospheric-spatial propagation of radio waves on the paths of the ZGRL.

The essence of the invention

The solution of the problem and the achievement of the claimed technical result is ensured by the fact that the method for adequately determining the current intervals of relative stationarity (RST) of ionospheric-spatial propagation of radio waves (IPRRV), which consists in cyclic with a period T over-the-horizon radar (OHRL) by transmitting by a radio transmitter (RPD) at the beginning of each cycle before the emission of a standard probing signal (SS) two successively "trial" δ D-signals (VHZ / δ D-signals) displayed approximately by Dirac δ-functions: relatively long quasi-monochromatic signal δ Dƒ "switching on" with a duration of δ t pr ƒ and a relatively short strobe pulse δ Dτ with a duration of δ tprτ, standard radio reception and processing of the corresponding received "trial" signals and taking into account their location delay, characterized in that:

выполняют путем последовательной коммутации в начале каждого текущего цикла ВНЗ/δ_Д-зондирования принятых «пробных» сигналов

и

на отдельные входы узла ОСТ, анализа на интервале δ t _прƒ комплекса частотных характеристик (

) _i принятых квазимонохроматических «пробных» сигналов «включения»

, обусловленных передачей сигнала δ_{Д ƒ} , затем, с момента окончания сигнала

и одновременного начала сигнала

, - анализа на интервале δ t _прτ совокупности параметров по задержке (

) _i принятых строб-импульсов

, обусловленных передачей сигнала δ_Дτ, последующей генерации на основе полученных данных о параметрах принятых сигналов

представлений соответствующих моделей (

) _i , (

) _i по частоте ƒ и задержке τ_з, определения нормированных показателей

текущих, на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования, относительных изменений характеристик ИПРРВ по ƒ и τ_з, принятия далее по показателям

частных решений о критичном изменении или сохранении на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования текущего состояния ИПРРВ и его оценке как интервала значимого изменения или сохранения состояния относительной стационарности ИПРРВ по частоте или задержке по критерию «больше-или-меньше»

≥

≥

- соответственно о выходе этих показателей из пределов

и

оперативно задаваемого порога

относительной стационарности

и

или об их малых вариациях в этих пределах, затем - принятия по критерию совпадения частных решений об отсутствии на текущем интервале Тδ _i сверхпороговых изменений показателей относительной стационарности ИПРРВ по частоте и задержке итогового решения об оценке этого интервала как интервала δ t _{ст i} относительно стационарного ИПРРВ, определения далее продолжительности непрерывного интервала относительной стационарности δ t _ст

суммированием идущих без перерывов периодов Тδ _i , в которых сохраняется полученная оценка δ t _{ст i} текущего состояния ИПРРВ;- processing of received "trial" signals

are performed by sequential switching at the beginning of each current cycle BHZ / δ_D-probing of received "trial" signals

and

to separate inputs of the OST node, analysis on the interval δt _prƒ complex frequency characteristics (

) _i received quasi-monochromatic "trial" signals "on"

, due to signal transmission δ_{D ƒ} , then, since the end of the signal

and simultaneous start of the signal

, - analysis on the interval δt _etcτ of the set of parameters in terms of delay (

) _i received strobe pulses

, due to signal transmission δ_Dτ, subsequent generation based on the obtained data on the parameters of the received signals

representations of the corresponding models (

) _i , (

) _i by frequencyƒ and delay τ_h, definitions of normalized indicators

current, on the interval fromi-th to (i +j)-th BIS cycle/δ_D-probing, relative changes in the characteristics of IPRR byƒ and τ_h, further adoption by indicators

private decisions about a critical change or preservation on the interval fromi-th to (i +j)-th BIS cycle/δ_D-probing the current state of the IPRT and its assessment as an interval of significant change or maintaining the state of relative stationarity of the IPRT in terms of frequency or delay according to the "more-or-less" criterion

≥

≥

- respectively, on the output of these indicators from the limits

and

operational threshold

relative stationarity

and

or about their small variations within these limits, then - making, according to the criterion of coincidence, particular decisions about the absence on the current intervalTδ _i over-threshold changes in indicators of relative stationarity of IPRR in terms of frequency and delay of the final decision on the assessment of this interval as an interval δt _{st i} relative to the stationary IPRR, further determination of the duration of the continuous interval of relative stationarity δt _st

summation of periods without breaksTδ _i , in which the resulting estimate δt _{st i} the current state of the IPRRV;

) _i квазимонохроматических «пробных» сигналов

, принятых в начале периода Тδ _i , определяют на интервале δ t _прƒ как совокупность их амплитудно-частотных характеристик { A_{m ƒ i} , ƒ _{m i} , σ _{ƒ 3}, σ _{ƒ 10}} _ƒ , где: A_{m ƒ i} - max. амплитуда, ƒ_{m i} - частота, соответствующая A_{mƒ i} , σ _{ƒ 3} и σ _{ƒ 10} - ширина частотного спектра по уровням соответственно -3 дБ и -10 дБ, и доплеровского сдвига δ ƒ _Д в каждом элементе разрешения РЛС, совокупность параметров по задержке (

) _i принятых строб-импульсов

определяют по окончании сигнала «включения» на интервале δ t _пр τ как совокупность их амплитудно-дальностных характеристик {A _{m 3 j} , τ_{3 m j} , σ τ_{3 j} , σ τ_{10 j} } τ , где A _{m 3 i} - амплитуда максимумов дискретных мод по задержке принятых сигналов ВНЗ/δ_Д-зондирования, τ_{3 m I} - положение дискретных позиций по задержке, определяемое по положению A _{m 3 i} по задержке, σ τ_{3 j} и σ τ_{10 j} - ширина спектров рассеяния задержек в «окрестностях» дискретных позиций τ_{3 m i} указанных дискретных мод по уровням соответственно -3 дБ и -10 дБ, и интервалов по задержке δ τ₃ между максимумами A _{m 3 i} в каждом элементе разрешения РЛС на каждой частоте ВНЗ/δ_Д-зондирования; - a complex of frequency characteristics (

) _i quasi-monochromatic "trial" signals

taken at the beginning of the periodTδ _i , determined on the interval δt _prƒ as a set of their amplitude-frequency characteristics { A_{m ƒ i} , ƒ _{m i}, σ _{ƒ 3}, σ _{ƒ 10}} _ƒ , where: A_{m ƒ i} - max. amplitude, ƒ_{m i} - frequency corresponding to A_{mƒ i} , σ _{ƒ 3} and σ _{ƒ 10} - the width of the frequency spectrum in terms of levels -3 dB and -10 dB, respectively, and the Doppler shift δƒ _Din each element of the radar resolution, the set of delay parameters (

) _i received strobe pulses

determined at the end of the "on" signal on the interval δt _etcτ as a set of their amplitude-range characteristics {A _{m 3 j} , τ_{3 m j} , σ τ_{3 j} , σ τ_{10 j} } τ , where A _{m 3 i} - the amplitude of the maxima of discrete modes by the delay of the received signals BIS / δ_D-probing, τ_{3 m I} - position of discrete positions by delay, determined by position A _{m 3 i} delay, σ τ_{3 j} and σ τ_{10 j} - the width of the delay scattering spectra in the "vicinities" of discrete positions τ_{3 m i} of the indicated discrete modes in terms of levels -3 dB and -10 dB, respectively, and intervals in terms of delay δ τ₃ between maxima A _{m 3 i} in each radar bin at each BIS/δ frequency_D- sounding;

текущих относительных изменений характеристик ИПРРВ на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования определяют независимо в сечениях частоты ƒ и задержки τ₃ в виде функциональной в L ₂ «невязки» i-х и (i+j)-х представлений моделей (

) принятых сигналов

.- indicators

the current relative changes in the characteristics of the IPRRV in the interval from the i -th to ( i + j )-th cycle of the BIS / δ _D -probing are determined independently in the sections of the frequency ƒ and delay τ ₃ in the form of a functional "residual" in L ₂ i -x and ( i+j )th representations of models (

) received signals

.

Evidence of achievement of the claimed technical result

≥

≥

, Estimation of the interval of significant change or maintenance of the state of relative stationarity of the IPRR by frequency or delay by the criterion

≥

≥

,

) _i квазимонохроматических «пробных» сигналов как совокупности их амплитудно-частотных характеристик {A_{m ƒ i} , ƒ _{m i} , σ _{ƒ 3}, σ _{ƒ 10}} _ƒ , где: A_{m ƒ i} - max. амплитуда, ƒ_{m i} - частота, соответствующая A_{mƒ i} , σ _{ƒ 3} и σ _{ƒ 10} - ширина частотного спектра по уровням соответственно -3 дБ и -10 дБ, и доплеровского сдвига δ ƒ _Д в каждом элементе,definition of a complex of frequency characteristics (

) _i quasi-monochromatic "trial" signals as a set of their amplitude-frequency characteristics {A_{m ƒ i} , ƒ _{m i}, σ _{ƒ 3}, σ _{ƒ 10}} _ƒ , where: A_{m ƒ i} - max. amplitude, ƒ_{m i} - frequency corresponding to A_{mƒ i} , σ _{ƒ 3} and σ _{ƒ 10} - the width of the frequency spectrum in terms of levels -3 dB and -10 dB, respectively, and the Doppler shift δƒ _D in each element

текущих относительных изменений характеристик ИПРРВ в виде функциональной в L2 «невязки» i-х и (i+j)-х представлений моделей (

) принятых сигналов

позволяют повысить степень адекватности оценки интервалов стационарности сигналов ионосферно-пространственного распространения радиоволн и, как следствие, достичь заявленного технического результата, заключающегося в повышении точности измерений текущих интервалов относительной стационарности ионосферно-пространственного распространения радиоволн на трассах ЗГРЛ.as well as the presentation of the indicator

current relative changes in the characteristics of the IPRR in the form of a functional "discrepancy" in L2 of the i-th and (i + j)-th representations of the models (

) received signals

make it possible to increase the degree of adequacy of assessing the intervals of stationarity of signals of ionospheric-spatial propagation of radio waves and, as a result, to achieve the claimed technical result, which consists in increasing the accuracy of measurements of the current intervals of relative stationarity of ionospheric-spatial propagation of radio waves on the paths of GRRL.

Link to drawings

The essence of the invention is illustrated by a block diagram (Fig. 1) of the algorithm for processing sounding signals and adequate measurement of the numerical value of the current intervals of relative stationarity of the ionospheric-spatial propagation of radio waves on the paths of the ZGRL.

In FIG. 1, the position numbers indicate the following operations, displaying the above-described steps by the method:

и

, обусловленных передачей «пробных» сигналов δ _{Д ƒ} и δ _Дτ соответственно, на входы соответственно блоков 2 и 4 узла ОСТ, затем - сигналов

, обусловленных передачей штатного зондирующего сигнала (ЗС), на вход блока 17 - тракта обработки локационного сигнала (ЛКС); Operation 1. Sequential switching (taking into account the location delay) at the beginning of each current BIS/δ cycle _D-probing of received "trial" signals

and

, due to the transmission of "trial" signals δ _{D ƒ} and δ _Dτ, respectively, to the inputs of blocks 2 and 4, respectively, of the OST node, then to the signals

, due to the transmission of a regular probing signal (SS), to the input of block 17 - the path for processing the location signal (LCS);

) _i принятых «пробных» квазимонохроматических сигналов «включения»

длительностью δ t _{пр ƒ} ; Operation 2. Analysis at the beginning of each period T δ _i BHZ/δ _D -sounding on the interval δ t _{pr ƒ} of the complex of frequency characteristics (

) _i received "trial" quasi-monochromatic "switch-on" signals

duration δ t _{pr ƒ} ;

) _i принятых сигналов

; Operation 3. Model generation (

) _i received signals

;

) _i принятых «пробных» строб-импульсов

длительностью δ t _пр τ; Operation 4. Analysis in every cycle BHZ/δ_D-probing on the interval δt _etcτ, following the interval δt _{P pƒ} , set of delay characteristics (

) _i received "trial" strobe pulses

duration δt _etcτ;

) _i принятых сигналов

; Operation 5 . Model generation (

) _i received signals

;

текущих, на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования, относительных изменений характеристик ИПРРВ по частоте ƒ; Operation 6. Determination of the normalized indicator

current, on the interval from the i -th to ( i + j )-th cycle of the BIS / δ _D -sounding, relative changes in the characteristics of the IPRRV in frequency ƒ ;

) _i на период Тδ ; Operation 7. Model signal delays (

) _i for the period Т δ ;

) _i на период Тδ ; Operation 8 . Signal-model delays (

) _i for the period Т δ ;

текущих, на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования, относительных изменений характеристик ИПРРВ по задержке τ₃; Operation 9 . Definition of a normalized indicator

current, on the interval from the i -th to ( i + j )-th cycle of the BHZ/δ _D -sounding, relative changes in the characteristics of the IPRRV for the delay τ ₃ ;

с порогом относительной стационарности

и принятия по критерию «больше-или-меньше» пределов этого порога частного решения о критичном изменении или сохранении на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования текущего состояния ИПРРВ и оценке этого интервала как интервала значимого изменения или сохранения состояния относительной стационарности ИПРРВ по частоте ƒ; Operation 10. Comparison of the indicator

with a threshold of relative stationarity

and accepting, according to the “more-or-less” criterion, the limits of this threshold of private decisions about a critical change or preservation on the interval fromi-th to (i + j)-th cycle/δ_D-probing the current state of the IPRRP and evaluating this interval as an interval of significant change or maintaining the state of relative stationarity of the IPRRP in frequencyƒ;

и

порога

относительной стационарности ИПРРВ; Operation 11. Generation of limits

and

threshold

relative stationarity of IPRR;

с порогом относительной стационарности

и принятия по критерию «больше-или-меньше» пределов этого порога частного решения о критичном изменении или сохранении на интервале от i-го до (i + j)-го цикла ВНЗ/δ_Д-зондирования текущего состояния ИПРРВ и оценке этого интервала как интервала значимого изменения или сохранения состояния относительной стационарности ИПРРВ по задержке τ_3. Operation 12. Comparison of the indicator

with a threshold of relative stationarity

and acceptance according to the “more-or-less” criterion of the limits of this threshold, a particular decision on a critical change or preservation in the interval fromi-th to (i + j)-th cycle/δ_D-probing the current state of the IPRT and evaluating this interval as an interval of significant change or maintaining the state of relative stationarity of the IPRT in terms of delay τ_3.

Operation 13. Adoption, on the basis of partial decisions about the absence on the interval from the i -th to ( i + j )-th cycle of the BIS / δ _D -probing of superthreshold changes in the relative stationarity of the IPRR in frequency and delay, the final decision, according to the criterion of coincidence of particular solutions , by definition of this current interval as the interval δ t _{st i} of the relative stationarity of the IPRR.

Operation 14. Summation of continuously successive intervals δ t _{st i} , determining the duration of a continuous interval of relative stationarity δ t _{st Σ} .

Operation 15. Generation of cycles T δ BZ/δ _D -probing;

Operation 16. Generation of "trial" δ _D -signals;

Operation 17. LKS processing;

Operation 18. Generation of a reference signal for the LC processing path;

Operation 19. Generation of a probing signal.

Disclosure of the essence of the invention . According to FIG. 1, an adequate definition of the current intervals of relative stationarity (RST) of ionospheric-spatial propagation of radio waves (IRRP) in the ZGRL is as follows.

For BIS sounding, two special BIS/δ _D -signals spaced apart in time are used, which approximately have the properties of the Dirac δ _D -function. Such VNZ/δ _D -probing is carried out by sequential radiation of the RPD in turn of two "trial" signals: a relatively long quasi-monochromatic "on" signal with a duration of δ _{D ƒ} and a relatively short strobe pulse δ _D τ. These signals, being reflected from the layers of the ionosphere, probe the over-the-horizon area of the terrain and, being reflected in the opposite direction, are received by the radio receiver (RPU) of the ZGRL.

обрабатывают совместно с сигналами синхронизации циклов (с периодом Тδ _i ) ВНЗ/δ _Д и сигналами синхронизации длительности текущего интервала стационарности δ t _{ст i ,} полученных в результате операции 14 по суммированию непрерывно следующих друг за другом интервалов δ tстi определения продолжительности непрерывного интервала относительной стационарности δ t _{ст Σ} .In accordance with operation 1, the received signals

are processed together with the cycle synchronization signals (with a periodTδ _i ) BHZ/δ _D and synchronization signals for the duration of the current stationarity interval δt _{st i ,}obtained as a result of operation 14 by summing continuously successive intervals δ tsti for determining the duration of a continuous interval of relative stationarity δt _{st Σ} .

длительностью δ t пр ƒ, обусловленный излучением радиопередатчиком (РПД) относительно длительного, отображаемого приближенно δ -функцией Дирака. As a result of operation 1, a trial “on” signal is generated

duration δ t pr ƒ, due to radiation by a radio transmitter (RPD) relatively long, displayed approximately by the Dirac δ-function.

длительностью δ t пр ƒ в процессе операции 2 на интервале δ t _{пр ƒ} анализируется по комплексу частотных характеристик (

) _i . При этом комплекс частотных характеристик (

) _i принятых «пробных» сигналов

определяют как совокупность их амплитудно-частотных характеристик { A_{m ƒ i} , ƒ _{m i}, σ _{ƒ 3}, σ _{ƒ 10}} _ƒ , где: A_{m ƒ i} - max. амплитуда, ƒ_{m i} - частота, соответствующая A_{mƒ i} , σ _{ƒ 3} и σ _{ƒ 10} - ширина частотного спектра по уровням соответственно -3 дБ и -10 дБ, и доплеровского сдвига δ ƒ _Д в каждом элементе разрешения РЛС. Одновременно в процессе операции 2 для этого анализа используют ВНЗ/δ _Д-сигналы «включения» δ_{Д ƒ} , полученные при и генерация «пробных» δ Д-сигналов (ЗГ) δ _Д-сигналов (операция 14). Данные частотного анализа полученные в результате операции 2 далее используются в операции 3 по генерация модели (

) _i принятых сигналов

. При выполнении операции 3 используют сигналы синхронизации по длительности текущего интервала стационарности δ t _{ст i} , полученные в результате операции 14. Next signal

duration δ t pr ƒ during operation 2 on the interval δt _{etc ƒ} analyzed by a set of frequency characteristics (

) _i . In this case, the complex of frequency characteristics (

) _i received "trial" signals

are defined as a set of their amplitude-frequency characteristics { A_{m ƒ i} , ƒ _{m i}, σ _{ƒ 3}, σ _{ƒ 10}} _ƒ , where: A_{m ƒ i} - max. amplitude, ƒ_{m i} - frequency corresponding to A_{mƒ i} , σ _{ƒ 3} and σ _{ƒ 10} - the width of the frequency spectrum in terms of levels -3 dB and -10 dB, respectively, and the Doppler shift δƒ _Din each element of the radar resolution. Simultaneously, during step 2, BIS/δ is used for this analysis _D- “switch-on” signals δ_{D ƒ} , obtained at and generation of "trial" δ D-signals (ZG) δ _D-signals (operation 14). The frequency analysis data obtained as a result of operation 2 is further used in operation 3 to generate the model (

) _i received signals

. When performing operation 3, synchronization signals are used for the duration of the current stationarity interval δt _{article i}obtained as a result of operation 14.

в процессе операции 1 принятый пробный строб-импульс

длительностью δ t _прτ, обусловленный излучением РПД относительно короткого, отображаемого приближенно δ-функцией Дирака, строб-импульса δ _Дτ, анализируют (операция 4) совокупности параметров по задержке (

) _i принятых пробных сигналов

. Такую совокупность (

) _i определяют по окончании сигнала «включения» на интервале δ t _пр τ как совокупность амплитудно-дальностных характеристик {A _{m 3 j} , τ_{3 m j} , σ τ_{3 j} , σ τ_{10 j} } τ , где A _{m 3 i} - амплитуда максимумов дискретных мод по задержке принятых сигналов ВНЗ/δ _Д-зондирования, τ_{3 m i} - положение дискретных позиций по задержке, определяемое по положению A _{m 3 i} по задержке, σ τ_{3 j} и σ τ_{10 j} - ширина спектров рассеяния задержек в «окрестностях» дискретных позиций τ_{3 m i} указанных дискретных мод по уровням соответственно -3 дБ и -10 дБ, и интервалов по задержке δ τ₃ между максимумами A _{m 3 i} в каждом элементе разрешения ЗГРЛ на каждой частоте ВНЗ/δ _Д-зондирования. Данные анализа операции 4 используют далее по генерации (операция 5) соответствующей модели (

) _i . При этом в операции 5 используют сигналы синхронизации по длительности текущего интервала стационарности δ t _{ст i}, полученные в результате операции 14.Then, at the end of the received signal "on"

during operation 1 received probe strobe

duration δt _etcτ, due to the RPD radiation of a relatively short, displayed approximately δ-Dirac function, strobe pulse δ _Dτ, analyze (operation 4) sets of parameters for the delay (

) _i received probes

. Such a set (

) _i determined at the end of the "on" signal on the interval δt _etcτ as a set of amplitude-range characteristics {A _{m 3 j} , τ_{3 m j} , σ τ_{3 j} , σ τ_{10 j} } τ , where A _{m 3 i} - the amplitude of the maxima of discrete modes by the delay of the received signals BIS / δ _D-probing, τ_{3 m i} - position of discrete positions by delay, determined by position A _{m 3 i} delay, σ τ_{3 j} and σ τ_{10 j} - the width of the delay scattering spectra in the "vicinities" of discrete positions τ_{3 m i} of the indicated discrete modes in terms of levels -3 dB and -10 dB, respectively, and intervals in terms of delay δ τ₃ between maxima A _{m 3 i} in each resolution element of the GRRL at each frequency of the BIS/δ _D- sounding. The analysis data of operation 4 is used further on generation (operation 5) of the corresponding model (

) _i . In this case, in operation 5, synchronization signals are used for the duration of the current stationarity interval δt _{article i}obtained as a result of operation 14.

текущих, на интервале от i-го до (i + j)-го цикла ВНЗ/δ _Д-зондирования, относительных изменений характеристик ИПРРВ по частоте ƒ; задержки сигналов моделей (

)_i и (

)_i на период Тδ и формируют таким образом их копии (

) _{( i + j )} , (

) _{( i + j ) .} The results of signal processing during operations 3 and 5 are used further to determine (operation 6) the normalized indicator

current, on the interval fromi-th to (i +j)-th BIS cycle/δ _D-probing, relative changes in the characteristics of IPRR by frequencyƒ; model signal delays (

)_i and (

)_i for a period ofTδ and thus form their copies (

) _{( i + j )} , (

) _{( i + j ) .}

)_i и (

)_i на период Тδ и формируют таким образом их копии (

) _{( i + j )} , (

) _{( i + j )} . Далее сформированные копии сигналов (

) _{( i + j )} , (

) _{( i + j )} используют для 6 и 9. для определения (операция 6) показателей относительной стационарности

и

в виде функциональной в L ₂ «невязки» i-х и (i+j)-х представлений (операция 9) моделей (

) принятых сигналов

в сечениях частоты и задержки. Сигналы, полученные в результате этих операций (6,9), сравнивают далее в со значениями пределов

(операция 10) и

(операция 12) оперативно задаваемого порога

. В процессе операций 10 и 12 по критерию больше-или-меньше порога

≥

≥

вырабатывают частные решения о критичном относительном изменении или сохранении на интервале от i-го до (i + j)-го цикла ВНЗ/δ _Д -зондирования параметров принятых сигналов

независимо по частоте и задержке и о соответствующем критичном относительном изменении или сохранении текущего состояния ИПРРВ. Сигналы, превысившие пороговое значение в операциях 10 и 12 сравниваются (операция 13), по критерию совпадения полученных ранее в сечениях ƒ и τ₃ частных решений об отсутствии на текущем интервале Тδ _i сверхпороговых изменений показателей относительной стационарности ИПРРВ по частоте и задержке принимают итоговое решение об оценке этого интервала как интервала δ t _{ст i} относительно стационарного ИПРРВ. Итоговое решение о сохранении степени стационарности полученное в операции 13 используют затем для определения (операция14) суммарного интервала идущих без перерывов периодов Тδ, в которых сохраняется текущее состояние стационарности, то есть - оценки общего непрерывного интервала стационарности δ t _{ст Σ}. Для этого в операции 14 одновременно используют сигналы синхронизации по циклам Тδ _i . Одновременно с заданным темпом производится генерация (операция 15) циклов Тδ ВНЗ/δ _Д-зондирования и на их основе генерация (операция 16) «пробных» δ _Д-сигналов. Выполнение описанных действий в указанной последовательности позволяет преодолеть недостатки известных способов оценки стационарности ИПРРВ, реализовать новый способ оперативных и адекватных измерений в реальном времени текущих интервалов относительной стационарности ИПРРВ на трассах ЗГРЛ.Then delay (operation 7) signals of models (

)_i and (

)_i for a period ofTδ and thus form their copies (

) _{( i + j )} , (

) _{( i + j )} . Next, the generated copies of the signals (

) _{( i + j )} , (

) _{( i + j )} used for 6 and 9. to determine (operation 6) indicators of relative stationarity

and

as a functionalL ₂ "discrepancy"i-x and (i+j)-x representations (operation 9) of models (

) received signals

in frequency and delay sections. The signals obtained as a result of these operations (6.9) are further compared with the values of the limits

(operation 10) and

(operation 12) operational threshold

. During operations 10 and 12 according to the criterion more-or-less than the threshold

≥

≥

develop private decisions about a critical relative change or conservation on the interval fromi-th to (i + j)-th cycle/δ _D -probing parameters of received signals

regardless of frequency and delay and the corresponding critical relative change or maintenance of the current state of the IPRT. The signals that have exceeded the threshold value in operations 10 and 12 are compared (operation 13), according to the criterion of coincidence obtained earlier in the sectionsƒ and τ₃ particular decisions about the absence on the current intervalTδ _i of over-threshold changes in indicators of relative stationarity of the IPRT in terms of frequency and delay, they make the final decision on evaluating this interval as an interval δt _{st i} relative to the stationary IPRRV. The final decision on the preservation of the degree of stationarity obtained in operation 13 is then used to determine (operation 14) the total interval of periods without breaksTδ, in which the current state of stationarity is preserved, that is, estimates of the total continuous interval of stationarity δt _{st Σ}. To do this, in operation 14 simultaneously use the synchronization signals in cyclesTδ _i . Simultaneously with the given tempo, the generation (operation 15) of cycles is performedTδ BHZ/δ _D- sounding and based on themGgeneration (operation 16) of "trial" δ _D-signals. The implementation of the described actions in the specified sequence allows to overcome the shortcomings of the known methods for estimating the stationarity of the IPRT, to implement a new method for prompt and adequate measurements in real time of the current intervals of relative stationarity of the IPRT on the paths of the ZGRL.

ZG radar when applying the proposed method becomes a radio device with a sliding adaptation to non-stationarity IPRRV. It is important to note that the described method of current moving relative estimates of the stationarity of DCM radio channels is invariant with respect to the operating conditions, methods of processing radio signals and their implementation.

The main factors determining the advantages of the proposed method over the known ones are:

- the adequacy and efficiency of current estimates of the intervals of relative stationarity of the GRRL paths, because of this - their independence from regular and fluctuating changes in HFCs in seasonal-daily cycles and periods of solar activity;

- invariance of the obtained estimates of stationarity of the IPRR with respect to the geography of the ZGRL routes and their directions;

- invariance of the obtained estimates of stationarity in relation to the methods of signal processing in the GRRL.

- the absence of most of the conditions and assumptions used a priori (in various combinations) that make the known methods of statistical estimates of the stationarity of the IPRT in the general case in the USF not adequate;

- the formation of two-dimensional estimates of the relative stationarity of the IPRR, to the maximum extent possible, corresponds to the real and most difficult in the general case, the conditions for the formation of algorithms for adapting the MG radar.

Industrial Applicability

The invention has been developed at the level of a technical proposal and mathematical modeling. The task was to determine the intervals of stationarity of the received signal, given with an envelope according to the normal law with arbitrary variations of the trend and amplitude changes. The results of stationarity estimates with errors of no more than 5% are obtained.

Information sources used

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4. Ishimaru A. Propagation and scattering of waves in randomly inhomogeneous media. - M., Mir, 1981, vol. 1, 2.

5. Ambartsumov K.S., Arefiev V.I., Gordeev V.A., Talalaev A.B. Generalized functional analysis of information radio systems. - Tver, Vestnik TVGU. Series "Applied Mathematics", 2015, No. 1.

6. Gerasimov Yu.S., Gordeev V.A., Kristal V.S. Estimation of the parameters of disturbing influences on the routes of long-range radio communication. - M., "Radio engineering", 1982, No. 9.

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10 Price R., Green P.E. A communication technique for multipatch channels. PIRE, v.46, no. 3, 1958.

11. Yakovlev O.I., Yakubov V.P., Uryadov V.P., Pavel'ev A.G. Propagation of radio waves. - M, publishing house URSS, 2015.

12. Vertogradov G.G. Comprehensive studies of the ionospheric propagation of decameter radio waves on paths of different lengths. Diss. for the degree of Doctor of Physics and Mathematics. Sciences. - Rostov-on-Don, 2007, 432 p.

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Claims (3)

A method for adequately determining the current intervals of relative stationarity (RST) of ionospheric-spatial propagation of radio waves (IPRRW), which consists in cyclic with a period of T _δ back-tilt sounding (VHZ / δ _D -sounding) of over-the-horizon radar (ZGRL) routes by transmitting a radio transmitter (RPD) at the beginning of each cycle, before the regular probing signal (SS) is emitted, successively two “trial” δ _D -signals (BIS/δ _D -signals) are displayed approximately by Dirac δ - functions: relatively long-term quasi-monochromatic signal

"on" duration

and a relatively short strobe pulse

duration

standard radio reception and processing of the corresponding received "trial" signals

and

taking into account their location delay, characterized in that: - processing of received "trial" signals

are performed by sequential switching at the beginning of each current cycle of BIS / δ _D -probing of the received "trial" signals

and

to separate inputs of the OST node, analysis on the interval

complex frequency characteristics

received quasi-monochromatic "trial" signals "on"

, due to signal transmission

, then from the end of the signal

and simultaneous start of the signal

- analysis on the interval

set of delay parameters (

) _i received strobe pulses

, due to signal transmission

, subsequent generation based on the received data on the parameters of the received signals

representations of the corresponding models

by frequency ƒ and delay τ ₃ , definitions of normalized indicators

current, on the interval from the i -th to ( i + j )-th cycle of the BIS / δ _D -sounding, relative changes in the characteristics of the IPRRV for ƒ and τ ₃ , further adoption by indicators

of particular decisions on a critical change or preservation in the interval from the i -th to ( i + j )-th cycle of the BIS / δ _D -probing the current state of the IPRRV and its assessment as an interval of significant change or preservation of the state of relative stationarity of the IPRRV in frequency or delay according to the criterion "more or less"

- respectively, on the output of these indicators from the limits

and

operational threshold

relative stationarity

and

or about their small variations within these limits, then making, according to the criterion of coincidence, particular decisions about the absence on the current interval

over-threshold changes in indicators of relative stationarity of the IPRR in terms of frequency and delay of the final decision on evaluating this interval as an interval

relative to the stationary IPRR, further determination of the duration of the continuous interval of relative stationarity

summation of periods without breaks

, in which the resulting estimate is stored

the current state of the IPRRV, - at the same time, the complex of frequency characteristics

quasi-monochromatic "trial" signals

taken at the beginning of the period

, determined on the interval

as a set of their amplitude-frequency characteristics

, where:

– max. amplitude,

is the frequency corresponding to

,

– the width of the frequency spectrum by levels, respectively -3 dB and -10 dB, and the Doppler shift

in each element of the resolution of the radar, the set of parameters for the delay

received strobe pulses

determined at the end of the "on" signal on the interval

as a combination of their amplitude-range characteristics

, where

is the amplitude of the maxima of discrete modes by the delay of the received BIS/δ _D -sounding signals,

– the position of discrete positions by delay, determined by the position

by delay

is the width of the delay scattering spectra in the “vicinities” of discrete positions

of the indicated discrete modes in terms of levels -3 dB and -10 dB, respectively, and intervals in terms of delay

between highs

in each element of the resolution of the radar at each frequency of the BIS / δ _D -sounding, and the indicators

the current relative changes in the characteristics of the IPRRV in the interval from the i -th to ( i + j )-th cycle of the BIS / δ _D -probing are determined independently in the sections of the frequency ƒ and delay

in the form of functional in L ₂ "residuals" i -x and ( i + j )-x representations of models

received signals

.

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