CN105717486A - Positioning method and system for radio interference source - Google Patents

Abstract

The invention discloses a positioning method and system for a radio source in the civil aviation communication frequency. The method comprises that a) an eight-channel digital antenna array is used to receive scattering signals from an airplane to the interference source, and the frequency spectrum and corresponding time of the scattering signals are recorded; b) an ADS-B receiver is used to receive a data link broadcast of the airplane, and receive flight state parameters of the airplane; c) according to the frequency spectrum and time, the azimuth of the interference source is calculated, and Doppler frequency shift is obtained; and d) according to the Doppler frequency shift and the flight state parameters of the airplane, a position curve of the interference source is calculated, and the interference source is positioned by combining orientation information of the interference source. According to the method and system of the invention, single-station positioning is used, the working range is large, the maintenance cost is low, problems in searching the interference source in the civil aviation communication frequency can be solved effectively, and the practicality is higher.

Description

Radio interference source localization method and system

Technical field

The present invention relates to radio monitoring technology, concretely, relate to the radio interference source localization method of a kind of aircraft With system.

Background technology

Since in April, 2004, it is subjected to terrestrial radio signal disturbing during civil aviation frequency range 108～137MHz, sternly Heavily threaten the flight safety of airline carriers of passengers.Location currently for this interference source mainly utilizes mobile monitoring car, in airport And frequency range special to civil aviaton is monitored near Waypoint, emphasis monitors civil aviaton's special frequency band signals service condition, and analysis is No genus normal Commercial Air Service signal, if register in station storehouse, and be analyzed abnormal signal, it is fixed to carry out illegal signals Position.But, based on existing monitoring means and facility, monitoring and protection to civil aviaton's frequency range have disappearance.When malice occurs During interference, it is many that interference relates to video transmission equipment, cable TV signal leakage, f-m broadcast station, high-power wireless phone etc. Planting interference, the most illegally setting, the black broadcast of Misuse, the impact on earth-space communication is the most serious.Existing monitoring, survey To technology, because of reception antenna limited height, overland propagation loss is big, it is difficult to the regional extent that cover jamming source exists, it is impossible to fast Speed, find, suppress and position ground interference source accurately.

Summary of the invention

It is an object of the invention to provide a kind of radio interference source localization method and system, by catching interference signal warp The signal that falls earthward after aircarrier aircraft scattering, utilizes the state of flight etc. of Doppler frequency shift that airplane motion produces and aircraft to believe Breath calculate interference source position, thus solve existing monitoring, direction-finding method be difficult to quickly, be accurately positioned interference source technology difficulty Topic.

To achieve these goals, the technical scheme is that

A kind of radio interference source localization method, it comprises the steps:

A. the eight passage numeral antenna array receiver aircrafts scattered signal to interference source, the frequency spectrum of record scattered signal are used And the time of correspondence；

B. use ADS-B (automatic dependent surveillance broadcast) receiver to receive the Data-Link broadcast of aircraft, obtain after decoding and fly The flight status parameter of machine；

C. according to described frequency spectrum and temporal information, calculate the azimuth of interference source, and obtain Doppler frequency shift；

D. according to Doppler frequency shift and the flight status parameter of aircraft, the position curve of interference source is calculated, in conjunction with interference source Azimuth information, it is achieved the location to described interference source.

Step a also includes: according to aircraft scattering resonance state select monitoring point, ground, the horizontal direction angle of aerial array and The elevation angle, is amplified the scattered signal of antenna array receiver.

Step b also includes: pretreatment and the decoding to ADS-B signal message.

The state of flight of described aircraft includes flying height, speed and position.

The azimuth of described interference source is calculated according to the scattered signal of eight passage antenna array receiver.

The position of described interference source obtains with the azimuthal angle calculation of described interference source according to the position curve of described interference source.

Described Doppler frequency shift includes Doppler frequency shift when interference source signal arrives aircraft and arrives the interference source of aircraft Signal scatters to Doppler frequency shift during ground again.

A kind of air interference source location system, comprising:

Aerial array, for receiving the aircraft scattered signal to interference source；

Receiver, for recording the frequency spectrum of described scattered signal and the time of correspondence thereof, it is defeated that described receiver has data Outgoing interface, exports for data；

ADS-B (automatic dependent surveillance broadcast) receiver, (includes flight shape for receiving the ADS-B broadcasting packet of aircraft State information)；

Data processing equipment, for the frequency spectrum of receiver output and time data, the aircraft of ADS-B receiver output ADS-B broadcasting packet carries out digital processing, calculates azimuth and the Doppler frequency shift of interference source signal of interference source, and according to institute The state of flight stating Doppler frequency shift and aircraft calculates the position curve of emission source, thus completes the location of emission source.

Air interference source location system also includes: low-noise amplifier, and the scattered signal of antenna array receiver is through low noise Amplifier is input to receiver after amplifying.

The gain of described aerial array is more than 11dBi.

The frequency resolution of described receiver is better than 1Hz.

Described Doppler frequency shift includes: Doppler frequency shift during emission source signal arrival aircraft and the emission source arriving aircraft Signal scatters to Doppler frequency shift during ground again.

The state of flight of described aircraft includes: flying height, speed and position.

It is an advantage of the current invention that:

Radio interference source localization method according to the present invention and system, efficiently solve civil aviaton's communication frequency interference source Searching problem, the present invention uses mono-station location, and action scope is big, and maintenance cost is low, can effectively solve civil aviaton's communication frequency interference Searching problem of source, practicality is stronger.Mobility strong, has saved again maintenance cost.

Accompanying drawing explanation

Fig. 1 is the structured flowchart of the radio interference source alignment system of the present invention；

Fig. 2 is the schematic diagram of object scatter；

Fig. 3 is the laying schematic diagram using aerial array in the embodiment of the present invention；

Fig. 4 is the hardware design flow figure of the ADS-B receiver used in the embodiment of the present invention；

Fig. 5 is to calculate the coordinate system that aircraft position is set up in the embodiment of the present invention.

Detailed description of the invention

Below in conjunction with drawings and Examples, the present invention is described in further detail.

The present invention is by receiving the aircraft scattered signal to interference source, how general extracting it from the scattered signal received Strangle frequency shift information, utilize Doppler shift information that interference source is positioned.Aircraft of the present invention not only includes that tradition is fixed Aircraft in justice, also includes other airborne aircraft.

Structured flowchart as it is shown in figure 1, a kind of air interference source location system of the present invention, including aerial array, amplifier, Receiver, ADS-B receiver, data processing equipment.

Aerial array, for receiving the aircraft scattered signal to interference source, due to the distance reception of signal to be realized, because of This present embodiment uses high gain directional antenna, it is desirable to gain is more than 11dBi；

Amplifier uses low-noise amplifier, is used for amplifying scattered signal, and the present embodiment uses civil aviaton's frequency range The special amplifier of (108MHz to 137MHz), it is desirable to definitely low noise and certain amplification.

Receiver uses high-sensitivity digital receiver, for record the frequency spectrum of scattered signal after amplification and correspondence thereof time Between, receiver has a data output interface, and after amplifying the frequency spectrum of scattered signal and the time output of correspondence thereof at data Reason device, high-sensitivity digital receiver requires have the highest receiving sensitivity in the special frequency range of civil aviaton, it is possible to high Frequency resolution (at least better than 1Hz) display and the frequency spectrum of non-volatile recording signal, to each moment while record Frequency spectrum stamps time labelling, provides digital channel simultaneously, to be connected with devices such as computers, it is simple to post analysis and process.

ADS-B receiver for receive aircraft ADS-B broadcasting packet (include aircraft identification code, longitude, latitude, highly, Time and other side information data etc.), and the message received is processed dress with the format transmission of the I&Q data of 8bit to data Put.

Data processing equipment uses high-performance computer, for connecing the frequency spectrum of receiver output and time data, ADS-B The ADS-B broadcasting packet of the aircraft of receipts machine output carries out digital processing, and the azimuth and the interference source signal that calculate interference source are many General Le frequency displacement, and the position curve of emission source is calculated according to the flight status parameter of described Doppler frequency shift and aircraft.

By described system, the location of radio interference source just can be realized.The radio interference source location of the present invention Method includes:

1) frequency spectrum and the time of correspondence of scattered signal are recorded

After receiving the interference complaint of department of civil aviaton, occur that position determines the big of interference source according to the interference of civil aviaton's Section report Cause scope, then according to the scattering resonance state of aircraft, in conjunction with course line distribution and surface state, selects monitoring point, ground and directivity The level orientation angle of antenna and the elevation angle.

The foundation selected is: ensureing can be with the biggest probability on selected place and corresponding aerial angle Capture the scattered signal in internal interference source, overlay area, i.e. for the incident angle that great majority point in overlay area is corresponding, and Scattering resonance state (RCS) under corresponding scattering angle is bigger.Such as, airline carriers of passengers is interfered in 120MHz frequency, permissible Call the Radar Cross Section data at 120MHz frequency, (be such as a step every 5 degree for each scattering angle Enter), the statistics RCS that all incident angles are corresponding under this frequency, this scattering angle, check that these RCS are more than certain predetermined door The probability of limit value.That of maximum probability can be found out with exhaustive all of scattering angle, then obtain monitoring station, optimal ground Position is relative to the angle of aircraft；The position being interfered in conjunction with aircarrier aircraft, can be obtained by ground by above-mentioned best angle The position of monitoring station, face.

Aircraft scattering resonance state can be calculated by computer simulation software in advance.Aircraft scattering section is described below Long-pending calculating.

When object is by electromagnetic wave irradiation, one way or another is scattered by energy.The spatial distribution of energy depends on object Shape, size and structure and the frequency of incidence wave and characteristic.This distribution of energy is referred to as scattering, and object itself is commonly referred to Target and scattering object.As in figure 2 it is shown, when scattering direction and not being directed to radiation source, referred to as EM scattering, present invention primarily contemplates The situation of EM scattering.

The definition of rebecca scattering section is based on the concept of target isotropic scatterning under plane wave illumination, for so A kind of ripple, its incident energy density isE in formula_iAnd H_iIt is the electric field of incident electromagnetic wave respectively Intensity and magnetic field intensity, Y₀It it is the admittance of free space.Therefore, the general power that target intercepts is In formula, σ represents the scattering section of target.

If these power isotropically radiate now, being then the distant place of R at distance objective, its scattered power is close Degree is:

$W_s=\frac{P}{4{\mathrm{\πR}}^2}=\frac{{\mathrm{\σY}}_0|E_i{|}^2}{8{\mathrm{\πR}}^2}---\left(I\right)$

But, scattered power density again can be by scattering electric field E_sRepresent:

$W_s=\frac{1}{2}{Y}_0|E_s{|}^2---\left(II\right)$

Make formula I and (II) formula equal, available

Because incidence wave is plane wave, and as it is assumed that target Equivalent is in point scatter, so distance R should tend to nothing Poor big.Thus, RCS formula can tighter be written asHere it is RCS Basic definition.

Use the computer simulation software (such as finite element emulation software) of existing calculating scattering section, select the typical people Boat aircraft model, calculates airline carriers of passengers radar scattering under different incidence, scattering angle in the special frequency range of civil aviaton and cuts Area (RCS):

1. set up model aircraft accurately, emulate the characteristic of aircarrier aircraft scattering field.For finite element algorithm, need Arranging radiation border, the distance of the model aircraft i.e. limiting the area of space of finite element iterative computation, this border and foundation must Must be more than 1/4 wavelength (wavelength can be converted by selected frequency), radiation border is the most similar to the shape of model；

2. setting into the direction of ejected wave (interference signal), and set into the character of ejected wave, what the present invention selected is vertical pole The spherical wave changed；

3. calculative characteristic frequency point is set；

4. iterative step and corresponding end condition (range of error) are set；

5. start iterative process, try to achieve the surface current of model aircraft；

6., after iterative computation terminates, the direction scope of scattered wave it is set and starts the calculating of RCS, can go out with one-time calculation The RCS in all scattering directions in the case of the incidence wave direction above arranged.

7. result is preserved.

8. change the parameter such as frequency, incidence wave direction, repeat above-mentioned calculating.

By said process, can obtain under the airline carriers of passengers of different model, different incidence angles degree, different frequency each dissipates Penetrate direction Radar Cross Section.

After selected ground monitoring point, set up ground monitoring station in relevant position.First pass through precise time reference source (example Such as GPS) all receptions, record analysis equipment are carried out time calibration, it is ensured that temporal Complete Synchronization.When interference letter occurs Number time, by antenna array receiver interference signal scattered signal of falling earthward after aircraft scatters, through alignment system of the present invention Special amplifier amplify after, described high-sensitivity digital receiver observe and record the frequency of scattered signal during interference appearance Spectrum, records corresponding precise time simultaneously.

2) flight status parameter of aircraft is obtained

In order to position ground interference source, it is thus necessary to determine that the state of flight of aircraft, including flying height, speed and position.This Invention utilizes decoding ADS-B broadcast (automatic dependent surveillance broadcast) message to realize aircraft real time position and extracts.

ADS-B is compared with traditional Ground-to-Air Data Link and radar system, and it is with low cost, it is easy to the advantage of enforcement seems The most prominent.Generally, air environment (GPS, Data-Link transceiver and antenna thereof, driving cabin punching are only needed Prominent information display CDTI), it is not necessary to any ground-support equipment can complete correlation function, and the aircraft being equipped with ADS-B can Himself exact position and other flight status parameter is broadcasted by Data-Link.According to investigation, the civil aviaton of the most domestic 70% flies Machine is equipped with ADS-B system, and especially its broadcast is plain code, and information is easily obtained.Ground installation has only to a receiver Coordinate decoder module, aircraft real-time flight parameter information can be obtained.

The ADS-B receiver that the present invention uses uses radio-frequency front-end, by field programmable gate array (FPGA) and numeral Signal processing chip (DSP) realizes the decoding of ADS-B signal.The main control chip of decoder module is the FPG A of altera corp Chip, dsp chip is C5000 series TMS320VC5509A of TI company.Requirement according to ADS-B signal decoding function and right The analysis of algorithm function, the hardware design flow determined is as shown in Figure 4.

First by FPGA, ADS-B signal message is carried out pretreatment work, including the detection of signal, header identification, rising Edge, trailing edge extraction and parameter calculating etc..The continuous sampling point of signal through FPGA process after, signal header and data segment Information separates, and data segment information is stored in internal memory (RAM).Then being sent interruption by FPGA to DSP, notice DSP extracts number External memory storage (EMIF) interface step-by-step is utilized to take out the information being saved in RAM after receiving interruptive command according to, DSP, and again Calculate reference power value.

After DSP completes the calculating of reference power, utilize the data samples obtained to be decoded, and calculate 112 circulations Redundant code (CRC) corrects son, is then stored in built-in RAM, in case the pattern that corrects a mistake during CRC check.The most right 112 data obtained by decoding carry out CRC check, and utilize rectification to carry out correction process, are led to by obtained data message Crossing UART interface and be back to high-performance computer, the generation completing message processes.

Form obtained by decoding is saved in SQL2005 data base, and respectively information preserves communication capacity, aircraft ID letter Breath, type of message, context information, antenna mode, synchronizing information, CPR coded format.The Position And Velocity of aircraft any time can To be obtained by inquiry data base.

3) calculate the azimuth of interference source, and obtain Doppler frequency shift

(1) azimuth of interference source is calculated

The present invention uses aerial array to determine the azimuth of interference source, and the laying of antenna array is as shown in Figure 3.8 antennas Array element puts composition antenna array in " one " font, and the distance of adjacent 2 bays is 1 meter of (1/ less than interference signal wavelength 2), 8 bays are connected by N-SMA joint and 8 low-noise amplifiers (LNA) respectively, and LNA is connect by SMA Head 8 passages with Agilent M9703A (8 channel receiver) respectively are connected.After receiving interference signal, receiver is by 8 The I&Q data of road signal preserve to high-performance computer.According to the 8 road I&Q data gathered, use MUSIC algorithm the most available The azimuth of interference source.

MUSIC algorithm is a kind of method based on matrix character spatial decomposition.Say from geometric angle, the observation of signal processing Space can be decomposed into signal subspace and noise subspace, it is clear that the two space is orthogonal.Signal subspace is by array Forming with signal characteristic of correspondence vector in the data covariance matrix received, noise subspace is then by institute in covariance matrix Minimal eigenvalue (noise variance) characteristic of correspondence vector is had to form.MUSIC algorithm utilizes between the two complementary space exactly Orthogonal property come the orientation of estimation space signal.

Assuming that the even linear array of M unit, array element distance is d, and signal wavelength is λ.Spacing wave source has D, and each signal is not Relevant, the noise n of each array element_m(t), m=1,2 ..., M is orthogonal, noise and signal S_k(t), k=1,2 ..., D the most not phase Close.Therefore, m-th array element is output as

$x_m\left(t\right)=\underset{k=1}{\overset{D}{\Σ}}{S}_k\left(t\right)e^{-j(m-1){\mathrm{\τ}}_k}+n_m\left(t\right)---\left(1\right)$

In formulaθ_kDirection for kth signal source.

Formula (1) can be rewritten into matrix form

X (t)=AS (t)+N (t)

In formula, X (t)=[x₁(t),x₂(t),...,x_M(t)]^TReception data vector for M dimension

S (t)=[s₁(t),s₂(t),...,s_D(t)]^TFor D dimensional signal vector

N (t)=[n₁(t),n₂(t),...,n_M(t)]^TNoise vector for M dimension

A=[a (θ₁),a(θ₂),...,a(θ_D)] be M × D dimension array manifold matrix

$a\left({\mathrm{\θ}}_k\right)={\[1,e^{-{\mathrm{j\τ}}_k},...,e^{-j(M-1){\mathrm{\τ}}_k}\]}^T$ Direction vector for M dimension

Matrix X^TTransposed matrix for matrix X.

Owing to the noise of each array element is orthogonal and also uncorrelated with signal, therefore receive the covariance square of data X (t) Battle array is:

R=E{X (t) X^H(t) }=E{AS (t) S^H(t)A^H+N(t)N^H(t) }=APA^H+σ²I (2)

In formula, P=E{S (t) S^H(t) }, σ²For the variance of noise N (t), I is unit matrix.

Matrix A is Vandermonde battle array, if θ_i≠θ_j, its row are the most separate.So can obtain matrix A PA^HOrder For D.Owing to P is positive definite, therefore matrix A PA^HEigenvalue be just, i.e. the eigenvalue that its total D is positive.σ in formula (2)²＞ 0, R is full rank battle array, and therefore it has the positive eigenvalue of M, and covariance matrix R is made feature decomposition, its each eigenvalue and corresponding Characteristic vector be respectively as follows:

λ₁≥λ₂≥...≥λ_D≥λ_D+1≥...≥λ_M

v₁,v₂,...,v_D,v_D+1,...v_M

And each characteristic vector is orthogonal, these characteristic vectors constitute one group of orthogonal basis of M × D dimension space.σ²For R Little eigenvalue, tuple is M-K.Number D in spacing wave source can be by D=M-n accordingly_MCalculate, n_MIt it is the number of minimal eigenvalue.

Owing to minimal eigenvalue is the contribution of noise, those therefore corresponding with minimal eigenvalue characteristic vectors are opened Subspace is also the contribution of noise, referred to as noise subspace, is designated as Ω_N.So, the column space of R is divided into two sub spaces, I.e. signal subspace Ω_SWith noise subspace Ω_N

Ω_N=span{v_D+1,...,v_M}

Ω_S=span{v₁,...,v_D}

Owing to each characteristic vector is mutually orthogonal, therefore there is Ω_S⊥Ω_N, on direction, signal source place, all direction vector a (θ_k), k=1,2 ... D, it is in signal subspace Ω_SIn, therefore a (θ_k)⊥Ω_N。

In order to obtain the direction of incoming signal, it is possible to use the orthogonality of two sub spaces, by all minimal characteristic vector structures A M × (M-D) is caused to tie up noise feature vector matrix E_N

E_N=[v_D+1,v_D+2,...,v_M]

Obviously have $E_N^{H}a\left({\mathrm{\θ}}_k\right)=0$

On the right of above formula, 0 is null vector.

Owing to covariance matrix R obtains according to limited number of time observation data estimation, when it is carried out feature decomposition, minimum The estimation of eigenvalue and the determination of tuple and minimal characteristic vector all has error, works as E_NWhen there is deviation, desirable make2 rank norms be the θ of minima_kValuation as kth signal source direction.Generally way is to utilize noise empty Between with the orthogonality of signal subspace, be constructed as follows spatial spectrum function

$P\left(\mathrm{\θ}\right)=\frac{1}{a^H\left(\mathrm{\θ}\right)E_N{E}_N^{H}a\left(\mathrm{\θ}\right)}$

The θ that spectral function maximum is corresponding is exactly the estimated value of signal source direction.

MUSIC algorithm calculation procedure is as follows:

1. the correlation matrix of estimated matrix is carried out by array data, if output signal vector representation is X (n)=[x₁(n),x₂ (n),...,x_M(n)]^TIf one has N number of data vector X (n), then

2. R is made feature decomposition, it is thus achieved that eigenvalue and characteristic vector v_i(i=1,2 ... M)；

3. carried out minimal eigenvalue number judgement by the eigenvalue of R, construct noise feature vector matrix E_N；

4. according to signal parameter scope by spatial spectrum functionCarry out spectrum peak search；

5. the direction that angle corresponding to maximum is exactly signal source is found out.

(2) Doppler frequency shift is obtained

Scattered signal can be drawn at the frequency spectrum of this time point by it at the Doppler frequency shift of different time points:

1. on frequency spectrum, find the peak of scattered signal, calculate its side-play amount (unit/sampling relative to spectral centroid frequency Point)

2. Doppler frequency shift=side-play amount/total sampling time

4) according to Doppler frequency shift and the flight status parameter of aircraft, the position curve of interference source is calculated, in conjunction with interference source Azimuth information, it is achieved the location to described interference source.

Set up the coordinate system shown in Fig. 5.Location, monitoring station is set to initial point, i.e. monitoring station in figure (0,0), x/y plane For ground；Assuming aircraft unaccelerated flight, course line is parallel to x-axis, and flying height is h [rice], and course line is at floor projection and prison The bias of survey station is y_p[rice], the coordinate of the i-th moment aircraft is (x_i[rice], y_p[rice]), interference source coordinate is (x_g[rice], y_g [rice])；Angle [alpha] in figure_iIt is the angle of the i-th moment aircraft and interference source line and heading, β_iIt is the i-th moment aircraft and prison Survey station line and the angle of heading.

1. Doppler frequency shift when jth moment interference signal arrives aircraft is:

${\mathrm{\Δf}}_{gj}=\frac{v}{c}\·{\mathrm{cos\α}}_i\·f_g=\frac{v}{c}\·\frac{x_g-x_j}{\sqrt{{(x_j-x_g)}^2+{(y_g-y_p)}^2+h^2}}\·f_g---\left(3\right)$

Wherein, f_g[hertz] is the frequency of interference signal, (x_g[rice], y_g[rice]) it is interference source coordinate, (x_j[rice], y_p [rice]) it is the coordinate of jth moment aircraft, wherein v [meter per second] is flight speed, and c is propagation velocity of electromagnetic wave (3 × 10⁸Rice/ Second).

2. jth moment (t_j) arriving the interference signal of aircraft when scattering to ground again, the Doppler frequency shift caused is:

Owing to (v/c) is much smaller than 1, omit square brackets in above formula interior with (v/c)²Section 2, obtain:

3. solving equations position of interference source is set up:

It is f for frequency_gInterference signal, the jth moment through aircraft scatter after arrive ground reception frequency be:

f_geti=f_g+Δf_gj+Δf_{G dissipates j}

Wherein: f_getj[hertz] is jth moment (t_j) in the frequency of ground receiver to interference source scattered signal.

(3), (4) formula are substituted into, obtain:

$f_g\·\[1+\frac{v}{c}\·\frac{x_g-x_j}{\sqrt{{(x_j-x_g)}^2+{(y_g-y_p)}^2+h^2}}+\frac{v}{c}\·\frac{-x_j}{\sqrt{x_j^2+h^2+y_p^2}}\]=f_{getj}---\left(5\right)$

Wherein j=1,2.

Position (x by the 1st moment Yu the 2nd moment aircraft₁[rice], y_p[rice]) (x₂[rice], y_p[rice]) substitute into (5) formula disappear Remove f_gObtain:

$\frac{1+\frac{v}{c}\·\frac{x_g-x_1}{\sqrt{{(x_1-x_g)}^2+{(y_g-y_p)}^2+h^2}}+\frac{v}{c}\·\frac{-x_1}{\sqrt{x_1^2+h^2+y_p^2}}}{1+\frac{v}{c}\·\frac{x_g-x_2}{\sqrt{{(x_2-x_g)}^2+{(y_g-y_p)}^2+h^2}}+\frac{v}{c}\·\frac{-x_2}{\sqrt{x_2^2+h^2+y_p^2}}}=\frac{f_{get1}}{f_{get2}}---\left(6\right)$

Interference source azimuth angle theta it is known that and have a following relation:

y_g=x_g tan(θ) (7)

Formula (7) is substituted into formula (6) position (x of ground interference source can be obtained_g,y_g)。

The position of interference source tried to achieve has two groups, is investigated by reality, can find actual interference source from two positions Position.

Embodiment:

2015 6, the research group of Country Radio Monitoring Center technical staff composition was in Daxing, Beijing civil aviaton flight boat Near line, aircraft scattered signal is utilized civil aviaton's frequency range radio interference source to carry out on-the-spot feasibility assignment test checking, continuously Capture aerodrome is same broadcasts the aircraft scattered signal with terrestrial communication frequency, and by the data gathered are analyzed and locate Reason, successfully broadcasts signal together to Nanyuan Airport, Beijing meteorology and is positioned.

Showing the positioning result of interference source, position error is less than 2km, and this shows to utilize aircarrier aircraft scattered signal over the ground The method that face interference source carries out positioning has been achieved with successfully.

Claims (5)

1. an air interference source location system, processes including aerial array, amplifier, receiver, ADS-B receiver, data Device；

Aerial array, for receiving the aircraft scattered signal to interference source；

Amplifier, is used for amplifying scattered signal；

Receiver, for recording frequency spectrum and the time of correspondence thereof of scattered signal after amplification, the frequency spectrum of scattered signal after amplifying And the time of correspondence exports to data processing equipment；

ADS-B receiver, for receiving the ADS-B broadcasting packet of aircraft, by the message transmissions of reception to data processing equipment；

Data processing equipment, for the frequency spectrum of receiver output and time data, the ADS-of aircraft of ADS-B receiver output B broadcasting packet carries out digital processing, calculates azimuth and the Doppler frequency shift of interference source signal of interference source, and according to described many The flight status parameter of general Le frequency displacement and aircraft calculates the position curve of emission source.

A kind of air interference source location system the most according to claim 1, described aerial array uses high-gain direction Antenna, gain is more than 11dBi.

A kind of air interference source location system the most according to claim 1, described amplifier uses low-noise amplifier.

4. a radio interference source localization method, it comprises the steps:

A. the antenna array receiver aircraft scattered signal to interference source, the frequency spectrum of record scattered signal and the time of correspondence are used；

Select monitoring point, ground, the horizontal direction angle of aerial array and the elevation angle according to aircraft scattering resonance state, use antenna array Row receive the aircraft scattered signal to interference source, the frequency spectrum of record scattered signal and the time of correspondence；

B. use ADS-B receiver to receive the Data-Link broadcast of aircraft, after decoding, obtain the flight status parameter of aircraft；

State of flight includes flying height, speed and position；

C. according to described frequency spectrum and temporal information, calculate the azimuth of interference source, and obtain Doppler frequency shift；

D. according to Doppler frequency shift and the flight status parameter of aircraft, the position curve of interference source is calculated, in conjunction with the side of interference source Position information, it is achieved the location to described interference source.

A kind of radio interference source localization method the most according to claim 4, in described step d:

Setting up coordinate system, location, monitoring station is set to initial point, be i.e. monitoring station (0,0), x/y plane is ground；Assume that aircraft is at the uniform velocity Rectilinear flight, course line is parallel to x-axis, and flying height is h, and course line is y in the bias of floor projection Yu monitoring station_p, the i-th moment The coordinate of aircraft is (x_i, y_p), interference source coordinate is (x_g, y_g)；If angle [alpha]_iIt is the i-th moment aircraft and interference source line and flight The angle in direction, β_iIt it is the angle of the i-th moment aircraft and monitoring station line and heading；

1. Doppler frequency shift when jth moment interference signal arrives aircraft is:

${\mathrm{\Δf}}_{gj}=\frac{v}{c}\·{\mathrm{cos\α}}_i\·f_g=\frac{v}{c}\·\frac{x_g-x_j}{\sqrt{{(x_j-x_g)}^2+{(y_g-y_p)}^2+h^2}}\·f_g---\left(3\right)$

Wherein, f_gFor disturbing the frequency of signal, (x_g, y_g) it is interference source coordinate, (x_j,y_p) it is the coordinate of jth moment aircraft, v is Flight speed, c is propagation velocity of electromagnetic wave；

2. jth moment t_jWhen the interference signal of arrival aircraft scatters to ground again, the Doppler frequency shift caused is:

Omit square brackets in above formula interior with (v/c)²Section 2, obtain:

3. solving equations position of interference source is set up:

It is f for frequency_gInterference signal, the jth moment through aircraft scatter after arrive ground reception frequency be:

f_geti=f_g+Δf_gj+Δf_{G dissipates j}

Wherein: f_getjFor jth moment t_jFrequency at ground receiver to interference source scattered signal；

(3), (4) formula are substituted into, obtain:

$f_g\·\[1+\frac{v}{c}\·\frac{x_g-x_j}{\sqrt{{(x_j-x_g)}^2+{(y_g-y_p)}^2+h^2}}+\frac{v}{c}\·\frac{-x_j}{\sqrt{x_j^2+h^2+y_p^2}}\]=f_{getj}---\left(5\right)$

Wherein j=1,2；

Position (x by the 1st moment Yu the 2nd moment aircraft₁, y_p)(x₂, y_p) substitute into (5) formula cancellation f_gObtain:

$\frac{1+\frac{v}{c}\·\frac{x_g-x_1}{\sqrt{{(x_1-x_g)}^2+{(y_g-y_p)}^2+h^2}}+\frac{v}{c}\·\frac{-x_1}{\sqrt{x_1^2+h^2+y_p^2}}}{1+\frac{v}{c}\·\frac{x_g-x_2}{\sqrt{{(x_2-x_g)}^2+{(y_g-y_p)}^2+h^2}}+\frac{v}{c}\·\frac{-x_2}{\sqrt{x_2^2+h^2+y_p^2}}}=\frac{f_{get1}}{f_{get2}}---\left(6\right)$

Interference source azimuth angle theta it is known that and have a following relation:

y_g=x_gtan(θ) (7)

Formula (7) is substituted into formula (6), it is thus achieved that the position (x of ground interference source_g,y_g)；

The position of interference source tried to achieve necessarily has two groups, is investigated by reality, finds the position in actual interference source from two positions.