阅读说明：本技术 一种对流层散射机制的识别方法 (A kind of recognition methods of tropospheric scatter mechanism ) 是由 石玲花 弓树宏 刘强 陈西宏 于 2019-08-22 设计创作，主要内容包括：一种对流层散射机制的识别方法,步骤如下：采集对流层散射回波电平时间序列数据；对采集到的实测数据进行分组；计算分组数据的均值和方差,并画出各分组数据的实测数据概率密度直方图和实测数据概率密度曲线图以及对应的莱斯概率密度理论曲线图和瑞利概率密度理论曲线图；将各分组数据的实测数据概率密度曲线图分别与对应的莱斯概率密度理论曲线图和瑞利概率密度理论曲线图进行比对,如果实测数据概率密度曲线与莱斯或瑞利概率密度理论曲线吻合,则根据莱斯分布或瑞利分布与散射机制的对应关系识别回波的散射机制,否则根据多莱斯分布与散射机制的对应关系识别回波的散射机制。本发明方法通过对实测回波数据的处理可实现对散射机制的识别。(A kind of recognition methods of tropospheric scatter mechanism, steps are as follows: acquisition tropospheric scatter echo level time series data；Collected measured data is grouped；The mean value and variance of packet data are calculated, and draws the measured data probability density histogram and measured data probability density curve figure and this probability density theory curve of corresponding Lay and Rayleigh probability density theory curve of each packet data；The measured data probability density curve figure of each packet data is compared with this probability density theory curve of corresponding Lay and Rayleigh probability density theory curve respectively, if measured data probability density curve and Lai Si or Rayleigh probability density theoretical curve coincide, the scattering mechanism that echo is then identified according to the corresponding relationship of L-S distribution or rayleigh distributed and scattering mechanism, otherwise identifies the scattering mechanism of echo according to the corresponding relationship of more L-S distributions and scattering mechanism.The identification to scattering mechanism can be achieved by the processing to actual measurement echo data for the method for the present invention.)

1. a kind of recognition methods of tropospheric scatter mechanism, which comprises the following steps:

Data acquisition；Acquire the tropospheric scatter echo level time series data in a certain period of time；

Data grouping；Collected measured data is grouped, and rejects pulsed data；

Obtain data graphs；The mean value and variance of each packet data are calculated, and draws the measured data of each packet data Probability density histogram and measured data probability density curve figure, while mean value and variance based on each packet data, according to Lay This distribution probability density function and rayleigh distributed probability density function draw this probability density theory curve of corresponding Lay respectively With Rayleigh probability density theory curve；

Curve graph comparison；The measured data probability density curve figure of each packet data is managed with this probability density of corresponding Lay respectively It is compared by curve graph and Rayleigh probability density theory curve, if the measured data probability density of a certain packet data is bent Line and this probability density theoretical curve of the Lay of the packet data coincide, then are known according to the corresponding relationship of L-S distribution and scattering mechanism The scattering mechanism of other echo, if the Rayleigh probability of the measured data probability density curve of a certain packet data and the packet data Density theory curve coincide, then the scattering mechanism of echo is identified according to the corresponding relationship of rayleigh distributed and scattering mechanism, if certain The measured data probability density curve and this probability density theoretical curve of the Lay of the packet data and Rayleigh probability of one packet data Density theory curve is misfitted, then according to the scattering machine of the corresponding relationship of bis- (more) L-S distributions and scattering mechanism identification echo System.

2. the recognition methods of tropospheric scatter mechanism according to claim 1, it is characterised in that: corresponding with L-S distribution Echo scattering mechanism are as follows: turbulent scattering echo mechanism or unstable incoherent reflecting layer echo mechanism are reflected back with stable phase dried layer Wave mechanism coexistence, either by the waveguide echo or atmospheric reflectance echo of path turbulent flow flicker effects；

Echo scattering mechanism corresponding with rayleigh distributed are as follows: turbulent flow incoherent scattering echo mechanism is unstable incoherent anti- Penetrate layer echo mechanism or turbulent flow incoherent scattering echo mechanism and unstable incoherent reflecting layer echo mechanism coexistence；

Echo scattering mechanism corresponding with bis- (more) L-S distributions are as follows: dual-mode antenna intersection region occur two or two with On the close turbulence structure of scale, be the reception signal that this mechanism of two or more Lays codetermines.

3. the recognition methods of tropospheric scatter mechanism according to claim 1 or 2, it is characterised in that: walked in data grouping Collected echo level time series data is grouped using envelope method in rapid, according to the probability density curve of data Peak value be grouped, enable the probability density curve of each packet data have and only one peak value.

4. the recognition methods of tropospheric scatter mechanism according to claim 1 or 2, it is characterised in that: compared in curve graph It is theoretical for measured data probability density curve and this probability density theoretical curve of corresponding Lay and Rayleigh probability density in step The packet data that curve is misfitted carries out analysis verifying to data using bis- (more) this addition method of Lay, forms total letter to determine Number random signal, steps are as follows:

S201, determine two L-S distributions random signal mean value α₁、α₂；

This probability density theoretical curve of double Lays of packet data is obtained according to the envelope probability density function p (E) of signal level, letter The envelope probability density function p (E) of number level are as follows:

In formula K is the Rice factor of L-S distribution, and Δ is double wave parameter, I₀Indicate that first kind zeroth order modified Bessel function, exp are indicated with e For the exponential function at bottom；

The value that Δ is searched between 0~1, finds highest with the measured data probability density curve goodness of fit of the packet data The envelope probability density function curve of signal level, the envelope probability density function curve with the highest signal level of the goodness of fit Corresponding Δ value is the final value of Δ；

Simultaneous Equations calculate α according to the following formula₁、α₂:

S202, (0, ψ₀) arbitrarily take in range a number as ψ₀₁Value, generate and meet the random number E of L-S distribution₁、E₂,

ψ in formula₀₁Indicate the variance of the one of random signal of the random signal of two L-S distributions, ψ₀For the side of packet data Difference；

S203, synthesis level magnitudes random number Data is calculated, and obtains the probability density curve of synthesis level magnitudes random number,In formulaWithIt is that 0~2 π of obedience divides equally the random of distribution respectively Number, j indicate imaginary unit；

S204, the probability density curve for synthesizing level magnitudes random number and measured data probability density curve are continued to compare, such as Fruit curve coincide, then can determine ψ₀₁The variance of the one of random signal of random signal of two L-S distributions, another with The variance ψ of machine signal₀₂According to resultant signal variance ψ₀And ψ₀₁It finds out；If curve is misfitted, return step S202 exists again (0,ψ₀) take in range a number as ψ₀₁Value, regenerates E₁、E₂, above step is repeated, until synthesizing level magnitudes random number Probability density curve and measured data probability density curve match, find out the random signal of two L-S distributions mean value and Variance can determine to form the random signal of the two of resultant signal L-S distributions.

5. the recognition methods of tropospheric scatter mechanism according to claim 1 or 2, it is characterised in that: data collection steps In, when the measured data of acquisition is performance number, level value is converted to as follows: E=P_t+20lgf-G_r+ 77.2, wherein G_rIt is antenna gain, f is the frequency that receiver receives signal, P_tIt is measured data.

Technical field

The invention belongs to tropospheric scatter communication technical field more particularly to a kind of identifications of troposphere scatter propagation mechanism Method.

Background technique

Troposphere scatter propagation phenomenon is found so far, to have relied on it not by ionosphere effect, passed from the 1930s It is (mainly military logical that the advantage of the uniqueness such as larger, few, long transmission distance of safe and secret and relay station of defeated capacity is largely used to communication Letter) field, and realize the propagation of tropospheric scatter beyond-the-horizon communication.Up to now, the workers of radio communication field are big Body propose three kinds of turbulent flow incoherent scattering, irregular layer incoherent reflecting and stabilized zone coherent reflection mechanism of transmission explaining and Troposphere scatter propagation phenomenon is supported, these three scattering mechanisms are all respectively provided with respective stringenter theoretical system and match Experimental data, therefore, tropospheric scatter communication has obtained good application in military and civilian field.

As the development of tropospheric scatter communication technology is more and more mature, there has been proposed application tropospheric scatter echoes to solve The certainly positioning and investigation problem of radiation source.The existing positioning investigative technique for over-the-horizon target radiation source is usually to use two The mode of the direction finding line cross bearing of direction finding site obtains the positions of emitter Signals, but this Passive Localization Technology is due to needing Two direction finding sites position to realize, use cost is high.The positioning for only realizing over the horizon radiation source with a direction finding site is ability Another research direction of domain workers, and realize that the key problem of over the horizon radiation source positioning is to scattering with a direction finding site The identification of scattering mechanism in communication process, then by the characteristic of scattering mechanism come the characteristic of inverting radiation source, therefore for right The identification of fluid layer beyond-the-horizon communication mechanism is the key that solve mono-station location, it should be understood that scattering machine in the positioning of over the horizon radiation source The Physical Mechanism of system and according to different scattering mechanisms come the characteristic of inverting radiation source, but at present there is no research be related to troposphere dissipate Penetrate the recognition methods of mechanism of transmission.

Summary of the invention

The object of the present invention is to provide a kind of methods that scattering mechanism is identified using tropospheric scatter echo data, thus The problems such as solving positioning, the investigation of tropospheric scatter over-the-horizon propagation radiation source.

To achieve the goals above, the present invention takes following technical solution:

A kind of recognition methods of tropospheric scatter mechanism, comprising the following steps:

Data acquisition；Acquire the tropospheric scatter echo level time series data in a certain period of time；

Data grouping；Collected measured data is grouped, and rejects pulsed bad data；

Obtain data graphs；The mean value and variance of each packet data are calculated, and draws the actual measurement of each packet data Data probability density histogram and measured data probability density curve figure, while mean value and variance based on each packet data, root The theoretical song of this probability density of corresponding Lay is drawn respectively according to L-S distribution probability density function and rayleigh distributed probability density function Line chart and Rayleigh probability density theory curve；

Curve graph comparison；By the measured data probability density curve figure of each packet data, this probability is close with corresponding Lay respectively Topology degree curve graph and Rayleigh probability density theory curve are compared, if the measured data probability of a certain packet data is close Line of writing music coincide with this probability density theoretical curve of the Lay of the packet data, then closes according to L-S distribution is corresponding with scattering mechanism The scattering mechanism of system's identification echo, if the Rayleigh of the measured data probability density curve of a certain packet data and the packet data Probability density theoretical curve coincide, then the scattering mechanism of echo is identified according to the corresponding relationship of rayleigh distributed and scattering mechanism, such as The measured data probability density curve and this probability density theoretical curve of the Lay of the packet data and Rayleigh of a certain packet data of fruit Probability density theoretical curve is misfitted, then dissipating according to the corresponding relationship of bis- (more) L-S distributions and scattering mechanism identification echo Penetrate mechanism.

Further, echo scattering mechanism corresponding with L-S distribution are as follows: turbulent scattering echo mechanism or unstable non-phase Dry reflecting layer echo mechanism and stable phase dried layer reflection echo mechanism coexistence, or the waveguide echo by path turbulent flow flicker effects Or atmospheric reflectance echo；

Echo scattering mechanism corresponding with rayleigh distributed are as follows: turbulent flow incoherent scattering echo mechanism or unstable non-phase Dry reflecting layer echo mechanism or turbulent flow incoherent scattering echo mechanism and unstable incoherent reflecting layer echo mechanism coexistence；

Echo scattering mechanism corresponding with bis- (more) L-S distributions are as follows: two or two occurs in dual-mode antenna intersection region The close turbulence structure of a above scale, is the reception signal that this mechanism of two or more Lays codetermines.

Further, in data grouping step using envelope method to collected echo level time series data into Row grouping, be grouped according to the peak value of the probability density curve of data, enable the probability density curve of each packet data have and Only one peak value.

Further, in curve graph comparison step, for measured data probability density curve and this probability of corresponding Lay The packet data that density theory curve and Rayleigh probability density theoretical curve are misfitted, using bis- (more) this addition method of Lay come pair Data carry out analysis verifying, and to determine the random signal for forming resultant signal, steps are as follows:

S201, determine two L-S distributions random signal mean value α₁、α₂；

This probability density theoretical curve of double Lays of packet data is obtained according to the envelope probability density function p (E) of signal level , the envelope probability density function p (E) of signal level are as follows:

K in formula is the Rice factor of L-S distribution, and Δ is double wave parameter, I₀Indicate that first kind zeroth order corrects Bezier letter Number, exp are indicated using e as the exponential function at bottom；

The value that Δ is searched between 0~1, finds with the measured data probability density curve goodness of fit of the packet data most The envelope probability density function curve of high signal level, the envelope probability density function with the highest signal level of the goodness of fit The corresponding Δ value of curve is the final value of Δ；

Simultaneous Equations calculate α according to the following formula₁、α₂:

S202, (0, ψ₀) arbitrarily take in range a number as ψ₀₁Value, generate and meet the random number E of L-S distribution₁、 E₂,

ψ in formula₀₁Indicate the variance of the one of random signal of the random signal of two L-S distributions, ψ₀For packet data Variance；

S203, synthesis level magnitudes random number Data is calculated, and the probability density for obtaining synthesis level magnitudes random number is bent Line,In formulaWithBe respectively 0~2 π of obedience divide equally be distributed with Machine number, j indicate imaginary unit；

S204, the probability density curve for synthesizing level magnitudes random number and measured data probability density curve are continued pair Than can determine ψ if curve coincide₀₁It is the variance of the one of random signal of random signal of two L-S distributions, it is another The variance ψ of a random signal₀₂According to resultant signal variance ψ₀And ψ₀₁It finds out；If curve is misfitted, return step S202, again (0, ψ₀) take in range a number as ψ₀₁Value, regenerates E₁、E₂, above step is repeated, until synthesis level magnitudes are random Several probability density curves and measured data probability density curve match, and find out the mean value of the random signal of two L-S distributions It can determine to form the random signal of the two of resultant signal L-S distributions with variance.

Further, in data collection steps, when the measured data of acquisition is performance number, electricity is converted to as follows Level values: E=P_t+20lgf-G_r+ 77.2, wherein G_rIt is antenna gain, f is the frequency that receiver receives signal, P_tIt is actual measurement Data.

From the above technical scheme, the present invention is based on different tropospheric scatter mechanism can generate different probability density type Number Physical Mechanism, pass through the probability density distributions of collected scatter echo data and theoretical Rayleigh, Lai Si, bis- (more) Lai Si The differentiation of scattering mechanism is realized in the comparative analysis of the probability density curve of distribution, thus to pass through the characteristic inverting of scattering mechanism The feature of over-the-horizon target radiation source, the final positioning for realizing over-the-horizon target radiation source and investigation provide technical support and theory Support, to solve the problems, such as how to identify scattering mechanism present in practical engineering application.

Detailed description of the invention

Fig. 1 is the flow chart of the method for the present invention；

Fig. 2 is the schematic diagram that envelope method is grouped the time series of actual measurement；

Fig. 3 is the step flow chart using bis- (more) this addition method of Lay analysis data；

Fig. 4 is the echo schematic diagram of narrow beam receive-transmit system electromagnetic wave and turbulent flow interaction；

Fig. 5 a is that broad-beam system electromagnetic wave and turbulent flow are mutual when dual-mode antenna intersection region dimension is greater than turbulent flow external measurement The echo schematic diagram of effect；

Fig. 5 b is broad-beam system electromagnetic wave and turbulent flow phase when dual-mode antenna intersection region dimension is much larger than turbulent flow external measurement The echo schematic diagram of interaction；

Fig. 6 is that two external measurements are L₁And L₂Turbulent flow fall into intersect volume when broad-beam system electromagnetic wave and turbulent flow it is mutual The echo schematic diagram of effect；

Fig. 7 is the echo schematic diagram of unstable incoherent reflecting layer interaction；

Fig. 8 is the echo schematic diagram of turbulent flow incoherent scattering and unstable incoherent scattering coexistence mechanism；

Fig. 9 is the stabilized zone coherent reflection echo schematic diagram by path Turbulent Flow Effects；

Figure 10 is this echo scattering mechanism schematic diagram of bis- (more) Lays；

Figure 11 is the actual measurement tropospheric scatter echo power data figure of emulation experiment；

Figure 12 is the level data figure surveyed after the conversion of tropospheric scatter echo power data；

Figure 13 a to Figure 13 f is respectively each packet data figure of emulation experiment data；

Figure 14 a to Figure 14 f is respectively the measured data probability density curve and Lai Si probability of each packet data of emulation experiment The comparison diagram of this superposition probability density curve of density theory curve, Rayleigh probability density theoretical curve, bis- (more) Lays.

Specific embodiment

Following will be combined with the drawings in the embodiments of the present invention, carries out to the technical solution of the embodiment of the present invention clear, complete Ground description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based on this Embodiment in invention, the every other implementation that those of ordinary skill in the art obtain without making creative work Example, shall fall within the protection scope of the present invention.

Inventors have found that tropospheric scatter echo-signal obeys certain statistical law, it thus can be according to the statistics of signal Rule obtains the corresponding relationship of different probability density and scattering mechanism, and basic ideas of the invention are dissipated using the troposphere of actual measurement Echo data is penetrated to differentiate the corresponding scattering mechanism of scattering link, by being grouped to the echo data of actual measurement, statistical property Analysis, the comparative analysis of data probability density curve and theoretical probability density curve can finally according to probability density distribution and dissipate The corresponding relationship for penetrating mechanism realizes the purpose of scattering mechanism identification.

It is core of the invention thought above, the technical solution of the embodiment of the present invention is clearly and completely retouched below It states, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is retouched in following Many details are elaborated in stating to facilitate a thorough understanding of the present invention, still the present invention can also be different from herein using other The other way of description is implemented, and those skilled in the art can do similar popularization without violating the connotation of the present invention, Therefore the present invention is not limited by the specific embodiments disclosed below.

Fig. 1 is the flow chart of the method for the present invention, is illustrated below with reference to Fig. 1 to the step of the method for the present invention, such as Fig. 1 institute Show, the step of the method for the present invention is as follows:

S101, data acquisition；Acquire the tropospheric scatter echo level time series data in a certain period of time, sampling Period is T, sampling interval t；According to the fast variation characteristic and experimental study experience of scatter echo, the sampling interval, t was preferably set It is 1 second or 0.5 second, the details that data change fastly can be effectively collected under the sampling interval.

S102, data grouping；Collected measured data is grouped, the present invention is using envelope method to collected Echo level time series data is grouped, and Fig. 2 is an echo level time series chart, carries out transition point using envelope method It when group, is grouped according to the peak value of the probability density curve of data, the probability density curve of each packet data is enabled to have and only There is a peak value, grouping while rejects using pulsed data as bad data.Group technology is specific as follows: based on original The envelope of acquisition data is grouped in advance, then draws the probability density curve of each pre- packet data, observes each pre- packet count According to probability density curve whether only one peak value, i.e., whether be single peak, if single peak then the pre- packet data point Group is correct；If not single peak, then left by a small margin by right endpoint under the premise of the left end point of this section of pre- packet data is constant It moves, the probability density curve of the pre- packet data after then drawing modification right endpoint, and observes the probability of pre- packet data at this time Density curve whether only one peak value, if it is pre- grouping amendment is completed, if not then moving right endpoint again simultaneously New probability density curve is drawn to be observed, until the probability density curve of the pre- packet data is single peak, when When the probability density curve of all pre- packet datas is single peak, grouping is completed.

S103, data graphs are obtained；The mean value and variance of each packet data are calculated, and draws each packet data Measured data probability density histogram and measured data probability density curve figure, while mean value and side based on each packet data Difference draws this probability density of corresponding Lay reason according to L-S distribution probability density function and rayleigh distributed probability density function respectively By curve graph and Rayleigh probability density theory curve；L-S distribution probability density function isRayleigh distributed probability density function is Wherein, E is signal level amplitude, ψ₀For the variance of packet data, α is the mean value of packet data, I₀Indicate the amendment of first kind zeroth order Bessel function, exp are indicated using e as the exponential function at bottom.

S104, curve graph comparison；By the measured data probability density curve figure of each packet data respectively with corresponding Lay this Probability density theory curve and Rayleigh probability density theory curve are compared, if the measured data of a certain packet data Probability density curve and this probability density theoretical curve of the Lay of the packet data coincide, then according to L-S distribution and scattering mechanism Corresponding relationship identifies the scattering mechanism of echo, if the measured data probability density curve of a certain packet data and the packet data Rayleigh probability density theoretical curve coincide, then according to the corresponding relationship of rayleigh distributed and scattering mechanism identify echo scattering machine System, if the measured data probability density curve of a certain packet data and this probability density theoretical curve of the Lay of the packet data and Rayleigh probability density theoretical curve is misfitted, then identifies echo according to the corresponding relationship of bis- (more) L-S distributions and scattering mechanism Scattering mechanism.

Echo scattering mechanism corresponding with L-S distribution are as follows: turbulent scattering echo mechanism or unstable incoherent reflecting layer return Wave mechanism and stable phase dried layer reflection echo mechanism coexistence (Fig. 5 a, 5b and Fig. 6), or by the waveguide of path turbulent flow flicker effects Echo or atmospheric reflectance echo (Fig. 9).

Echo scattering mechanism corresponding with rayleigh distributed are as follows: turbulent flow incoherent scattering echo mechanism (Fig. 4) is unstable Incoherent reflecting layer echo mechanism (Fig. 7)；Or turbulent flow incoherent scattering echo mechanism and unstable incoherent reflecting layer echo Mechanism coexistence (Fig. 8).

Echo scattering mechanism corresponding with bis- (more) L-S distributions are as follows: two or two occurs in dual-mode antenna intersection region The close turbulence structure of the scale of a above (within 5), is the reception signal that this mechanism of two or more Lays codetermines (Figure 10).

According to the Physical Mechanism of turbulent scattering, electromagnetic wave is similar to dipole in the intracorporal mechanism of turbulent scattering, rapid It will form charge inducing, induced current at internal fluid and turbulent flow external measurement boundary interface, the interface surface that external measurement determines Induced current and charge inducing are relatively stable within a certain period of time, and the induced current variation of rapid internal fluid is very fast.Therefore, plane Its physical process is equivalent to a stabilization " dipole " and many random " idols when wave and group's fluid matasomatism of external measurement determination The synergy result of extremely son ".It is possible thereby to think that the mechanism of troposphere over the horizon scattering link can be according to sending and receiving end day Line beam angle refines the process of its received field strong representation.

Turbulent flow incoherent scattering echo mechanism can be divided into three kinds according to the relationship for intersecting volume dimension and external measurement dimension Situation:

As shown in figure 4, if the dimension of dual-mode antenna intersection region is much smaller than turbulent flow external measurement, at this time external measurement interface Apparent charge inducing, induced current cannot be formed, signal is received and only has internal sub- turbulent flow random scatter signal to work, formed Electromagnetic wave and turbulent flow under narrow beam receive-transmit system interact.

As shown in Figure 5 a, if dual-mode antenna intersection region dimension is greater than turbulent flow external measurement, and only one external measurement is L Turbulent flow fall into intersection volume, then receiving signal is outer boundary charge inducing, induced current and internal sub- turbulent flow random scatter letter It number concurs, forms broad beam receive-transmit system electromagnetic wave and turbulent flow interacts.

As shown in Figure 5 b, if dual-mode antenna intersection region dimension is much larger than turbulent flow external measurement, a part of two turbulent flows Intersection volume is fallen into, then the charge inducing of formation, induced current at two turbulent flow large scale interfaces, reception signal are outer at this time Interface charge inducing, electric current and two groups of sub- turbulent flow random scatter signals in inside concur.

As shown in fig. 6, if dual-mode antenna intersection region dimension is much larger than turbulent flow external measurement, and there are two external measurements to distinguish For L₁And L₂Turbulent flow fall into intersection volume, then form the charge inducing at two external measurement interfaces, induced current at this time, receive letter It number is that two outer boundary charge inducings, electric current and two groups of sub- turbulent flow random scatter signals in inside concur.

Stable phase dried layer reflection echo mechanism is the interface of turbulent flow external measurement boundary or two macroturbulences to signal Scatter echo.

A series of unstable incoherent reflecting layer echo mechanism turbulent scattering dissipation later period independent microturbulence group shapes At interface group.Unstable incoherent reflecting interface (layer) is external measurement very little, inside not comprising subtleer turbulence process , turbulence structure body " group ", this " group " typically occur in macroturbulence dissipate the later period.Since each of this " group " is rapid Stream is internal not to have fine structure, so the scattered signal of each turbulent flow is very stable, forms dissipating for similar discrete Clustering particles It is emitted back towards wave effect, as shown in Figure 7.

Theoretically the probability density distribution situation of tropospheric scatter echo data has rayleigh distributed, L-S distribution, Shuan Laisi Distribution, three L-S distributions and four L-S distributions etc..Inventor is the study found that in practical projects, since tropospheric scatter is received The highly directive of hair antenna, high-gain make the wave beam of antenna relatively narrow, therefore the dimension and turbulent flow of the intersection region of dual-mode antenna The case where what external scale was formed is electromagnetic wave and the turbulent flow interaction under arrow-beam.Therefore in a practical situation, receive The case where sending out the interior appearance of antenna intersection volume three and the above turbulent flow body is seldom, even if occurring, due to intersecting volume dimension Problem, leading to the close turbulent flow that can be dissipated quickly as small scale of external measurement in turbulent flow body, " group is difficult to observe, i.e., troposphere dissipates The probability density distribution for being emitted back towards wave is in most cases to obey double L-S distributions, the feelings of rayleigh distributed, single L-S distribution Condition also will appear, and the probability that the case where three L-S distributions or four L-S distributions occurs is very low, without actual application value, because This present invention the case where three L-S distributions or four L-S distributions are not discussed still further, but by three L-S distributions or four L-S distributions The case where be uniformly placed in bis- (more) L-S distributions and discuss, in scattering mechanism identification, when the measured data of packet data When probability density curve is misfitted with this probability density theoretical curve of corresponding Lay and Rayleigh probability density theoretical curve, preferentially The case where considering double L-S distributions.

Measured data probability density curve is managed with this probability density theoretical curve of corresponding Lay and Rayleigh probability density The packet data misfitted by curve considers engineering practicability and preciseness, and the present invention further uses bis- (more) Lays, and this is folded Addition carries out verifying analysis to data, to determine the random signal for forming resultant signal, thus according to more L-S distributions and scattering The corresponding relationship of mechanism identifies the scattering mechanism of echo.Below with reference to Fig. 3 to using bis- (more) this addition method of Lay verifying analyses The specific steps of data are illustrated (to be obtained the part in Fig. 3 in dotted line frame corresponding to data acquisition, data grouping and data and curves Take step), its step are as follows:

S201, determine two L-S distributions random signal mean value α₁、α₂；

This probability density theoretical curve of double Lays of packet data can be according to the envelope probability density function p (E) of signal level It obtains, the envelope probability density function p (E) of signal level are as follows:

K in formula is the Rice factor of L-S distribution, Rice factor be main signal power and multi-path signal-component power it Than it is the ratio of main signal peak power and mean power that Δ, which is double wave parameter,；According to the mean value, variance and letter of packet data The envelope probability density function p (E) of number level can obtain this probability density theoretical curve of double Lays of the packet data；

The value that Δ is searched between 0~1, finds with the measured data probability density curve goodness of fit of the packet data most High envelope probability density function curve, Δ value corresponding with the highest envelope probability density function curve of the goodness of fit are Δ Final value；

Simultaneous Equations according to the following formula calculate α according to known K value and Δ value₁、α₂:

α in formula₁、α₂Respectively indicate the mean value of the random signal of two L-S distributions, i.e. α be two L-S distributions with The mean value of resultant signal after machine Signal averaging.

S202, (0, ψ₀) arbitrarily take in range a number as ψ₀₁Value generates the random number E for meeting L-S distribution₁、E₂,

E₁、E₂It is the level magnitudes of the random signal of two L-S distributions respectively, the ψ in formula₀₁Indicate one of Lay this The variance of the random signal of distribution, by resultant signal variance (i.e. the variance of packet data) and the random signal of two L-S distributions Relationship ψ between variance₀=ψ₀₁+ψ₀₂It is found that ψ₀₁Value range be (0, ψ₀), therefore can be (0, ψ₀) arbitrarily access is made in range For ψ₀₁Value (the variance ψ of the random signal of another L-S distribution₀₂=ψ₀-ψ₀₁) Lai Shengcheng random number E₁、E₂, can be used Matlab software directly generates the random number E of the L-S distribution of known mean value and variance₁、E₂。

S203, synthesis level magnitudes random number Data is calculated, and the probability density for obtaining synthesis level magnitudes random number is bent Line,In formulaWithBe respectively 0~2 π of obedience divide equally be distributed with Machine number can be directly generated with Matlab software, and j indicates imaginary unit.

S204, the probability density curve for synthesizing level magnitudes random number and measured data probability density curve are continued pair Than if curve coincide, bis- (more) this superposition theory of Lay are correct, it may be determined that ψ₀₁Be the random signal of two L-S distributions wherein The variance of one random signal, the variance ψ of another random signal₀₂It then can be according to resultant signal variance ψ₀And ψ₀₁It finds out；If bent Line is misfitted, then return step S202, again (0, ψ₀) take in range a number as ψ₀₁Value, regenerates E₁、E₂, repeat Above step, until the probability density curve and measured data probability density curve of synthesis level magnitudes random number match (in fact Scatter echo is in most cases the double L-S distributions of obedience in the situation of border, therefore (0, ψ₀) one can be found in range ψ₀₁Value is so that the probability density curve and measured data probability density curve of synthesis level magnitudes random number match), find out two The mean value and variance of the random signal of a L-S distribution can determine to form the random signal of the two of resultant signal L-S distributions.

Bis- (more) this addition method of Lay are to utilize bis- (more) Lai Si based on the probability density function of double-wave model theory When the addition method analyzes probability density curve, the selection of different L-S distribution mean values and variance is crucial.According to mean value and variance Physical significance is it is found that mean value is average level signal, and variance is the power of fluctuating level, so, when two random signals are folded After adding, the variance of resultant signal should be the sum of two random signal variances, i.e. ψ₀=ψ₀₁+ψ₀₂；And the mean value of resultant signal is not two The sum of person, i.e. α ≠ α₁+α₂, according to vector signal principle of stacking it is found that the value range of resultant signal mean value is | α₁-α₂|≤α≤α₁ +α₂, meet double-wave model probability density function random number, average power α₁ ²+α₂ ²。

The method of the present invention is illustrated below by emulation experiment below, experimental data is carried out using MATLAB software Processing.

Tropospheric scatter echo level time series is acquired using the antenna of variable beam width, the sampling period, T=24 was small When, sampling interval t=5s measures 17507 data points, and the reception frequency of antenna is 63MHz, and the data measured are single with dBm Position.When the measured data of acquisition is performance number (Figure 11), then the power time series measured are converted to according to following formula Level value: E=P_t+20lgf-G_r+ 77.2, wherein G_rIt is antenna gain, unit is (dBi), and f is that receiver receives signal Frequency, unit are (MHz), P_tIt is measured data, lg indicates denary logarithm.Datagram after conversion is as shown in figure 12. Collected data can be handled directly when being level value.

(Figure 13 a to Figure 13 f) is grouped to measured data, and rejects pulsed bad data.

Using the statistical tool packet in Matlab, the mean value, variance and measured data probability of each packet data are obtained Density histogram and measured data probability density curve figure, and using the statistical tool packet in Matlab by each packet data Mean value and variance substitute into L-S distribution probability density function and rayleigh distributed probability density function, and it is theoretical to draw this probability density of Lay Curve graph and Rayleigh probability density theory curve (Figure 14 a to Figure 14 f).

Successively by the measured data probability density curve figure of each packet data, this probability density is theoretical with corresponding Lay respectively Curve graph and Rayleigh probability density theory curve are compared, wherein first group, third group, the 4th group, the 6th group of packet count According to measured data probability density curve and this probability density theoretical curve of Lay coincide substantially, therefore can according to L-S distribution and The corresponding relationship of scattering mechanism identifies the scattering mechanism and first group, third group, the 4th group, the 6th group of packet data of echo The corresponding scattering mechanism of corresponding scattering link are as follows: turbulent scattering echo mechanism or unstable incoherent reflecting layer echo mechanism and The two kinds of effects of stable phase dried layer reflection echo coexist, or waveguide echo or atmospheric reflectance time by path turbulent flow flicker effects Wave.Second group and the 5th group of data both do not meet rayleigh distributed, L-S distribution are not met yet, using bis- (more) this addition method pair of Lay Data carry out multiple comparative analysis, the mean value and variance of two L-S distributions acquired in second group of data are as follows: α₁=1.46, ψ₀₁=2.56；α₂=1.20, ψ₀₂=1.12；The mean value and variance of two L-S distributions acquired in 5th group of data are as follows: α₁= 0.72、ψ₀₁=0.92；α₂=0.89, ψ₀₂=1.56, scattering machine can be differentiated according to the corresponding scattering mechanism of more L-S distributions The corresponding scattering mechanism of system scattering link corresponding with second group, fifth component group data are as follows: dual-mode antenna intersection region occurs The close turbulence structure of the scale of two or more (within 5) is that two or more Lays this mechanism is determined jointly Fixed reception signal.

The method of the present invention achievees the purpose that scattering mechanism is identified by the processing to actual measurement echo data, so as to logical The feature of the characteristic inverting over-the-horizon target radiation source of scattering mechanism is crossed, finally realize the positioning of over-the-horizon target radiation source and is detectd It looks into.

The above described is only a preferred embodiment of the present invention, limitation in any form not is done to the present invention, though So the present invention is disclosed as above with preferred embodiment, and however, it is not intended to limit the invention, any technology people for being familiar with this profession Member, without departing from the scope of the present invention, when the technology contents using the disclosure above are modified or are modified For the equivalent embodiment of equivalent variations, but anything that does not depart from the technical scheme of the invention content, according to the technical essence of the invention Any simple modification, equivalent change and modification to the above embodiments, all of which are still within the scope of the technical scheme of the invention.