Improved method for synthetic aperture radar scattered wave deception jamming

www.ietdl.org

IE

d

Published in IET Radar, Sonar and NavigationReceived on 26th October 2013Revised on 28th January 2014Accepted on 15th February 2014doi: 10.1049/iet-rsn.2013.0341

T Radar Sonar Navig., 2014, Vol. 8, Iss. 8, pp. 971–976oi: 10.1049/iet-rsn.2013.0341

ISSN 1751-8784

Improved method for synthetic aperture radarscattered wave deception jammingBo Zhao, Feng Zhou, Mingliang Tao, Zijing Zhang, Zheng Bao

National Laboratory of Radar Signal Processing, Xidian University, Xi’an 710071, People’s Republic of China

E-mail: [email protected]

Abstract: This study presents an improved scattered wave jamming method for synthetic aperture radar (SAR). The jammeradjusts the time-delay and the phase of the intercepted SAR signal. Then, a false scene is created to provide an effectiveprotection for a certain area. It requires a lower jamming power than barrage jamming and has less computational complexitythan direct-path deception jamming. Based on the performance analysis of scattered wave jamming, pulse repetition intervalsto delay retransmission, and a modulation centre shift are proposed as improvements to enlarge the jamming area.

1 Introduction

Synthetic aperture radar (SAR) has been widely utilised inboth military and civil applications because of thecapability of all-time, all-weather and high resolutionimaging [1–5]. Hence, the research on SAR jamming andanti-jamming has been one of the important subjects inelectronic countermeasure. According to electromagneticwave propagation path characteristics [6], SAR jammingcan be generally classified into direct-path jamming andmultipath jamming.Scattered wave jamming, also known as hot clutter or

terrain scattered interference, is one type of multipathjamming. Additionally, scattered wave jamming can bedivided into barrage jamming and deception jamming. Theinterference reflected by the ground while transmittingdirect-path barrage noise jamming is discussed in [7–13],where interference is cancelled by using the space–timeadaptive processing method. Gan et al. [14] and Wang andCai [15] proposed transmitting scattered wave jammingsignals with random time-delays to create a noise-likejamming for both SAR and bi-/multi-static SAR. Thismethod is simple in principle, but the transmission power ishigh [16, 17]. The scattered wave deception jammingsimulates a SAR signal to obtain a high processing gain,which may reduce the jamming power, discussed by Gaoand Lei [18]. Hu and Wu [19] analysed the effect ofDoppler parameter mismatch, and Liu et al. [20] consideredthe scattered wave jamming factor, and analysed thejamming results for different parameters. Gan et al. [21]analysed the performance of scattered wave jamming, andproposed two methods for jamming removal. However, thejammers in [18–21] transmit the jamming signals withoutmodulation, making it difficult for the jammers to controlthe location of the jamming scene. Time-delays and phasemodulations are introduced to take active control of thejamming scene in [22, 23]. Scattered wave deception

jamming just has to modulate the signal for the centre ofthe false scene, while the direct-path deception jamming hasto perform accurate modulation of echoes for each pointbetween pulses of the SAR [24–26]. This makes thescattered wave jamming much easier to realise. Thereflection of the ground can obtain a better jamming resultthan direct-path deception jamming for bistatic SAR [27].In this paper, we analyse the jamming area and propose an

improved method for scattered wave deception jamming toenlarge the jamming area while keeping its easy realisation.The principle of scattered wave deception jamming, whichhas been detailed discussed in [22, 23], is briefly presentedin Section 2, and limitations of its performance arediscussed in Section 3. Two methods for improvements areproposed in Section 4 to enlarge the jamming area.Simulation results are presented in Section 5 to validate theeffectiveness of the proposed methods. Section 6 concludesthis paper.

2 Geometry of scattered wave deceptionjamming

As illustrated in Fig. 1, the SAR platform flies along an idealstraight line with a constant velocity v. Its projection on theground at tm = 0 is set as the origin of the coordinatesystem, where tm is the slow time in azimuth. The x-axis isset parallel to the flight path with the direction of the SARvelocity being the positive direction. The z-axis isperpendicular to the ground and positive upwards. They-axis is decided according to the right-hand rule.The SAR sensor is denoted by point S, and its

instantaneous coordinates are (vtm, 0, H ) at tm, where H isthe altitude of the SAR. P(xP, yP, zP) is the point at whichthe centre of the beam pointing at tm = 0. It is also thecentre of area to be protected. The jammer is located at aground high tower with fixed coordinates J(xJ, yJ, zJ). It

971& The Institution of Engineering and Technology 2014

Fig. 1 Geometry of scattered wave deception jamming

www.ietdl.org

intercepts the SAR signal, modulates and retransmits it to theilluminated scene centred at I(xI, yI, zI). Jamming echoesscattered by point I appears in the SAR image as a falsepoint F. Point F is intended to superpose on point P afteraccurate modulation. Thus the real target P is covered byfalse target F.The SAR transmits linear frequency modulation (LFM)

signal with the following expression

s0 tr( ) = ar tr

( )exp j2pfctr

{ }exp jpgt2r

{ }(1)

where fc is the carrier frequency, tr is the fast time and γ is the

chirp rate of the LFM signal. And ar tr( ) = 1 tr

∣∣ ∣∣ ≤ Tp/2

0 tr∣∣ ∣∣ . Tp/2

{

is the rectangular envelope of the signal, Tp is the pulse width.According to the geometry shown in Fig. 1, the slant range

history of point P varying with tm is

RP tm( ) = SP| | + PS| |

= 2��(vtm − xP)

2 + y2P + H − zP( )2√ (2)

The echo of point P is obtained from (1) with a time-delay ofRP(tm)/c, where c is the speed of light. As fc has nocontribution to imaging processing, echoes are alwaysconverted to the baseband for receiving. The baseband echoof point P is

sP tr, tm( ) = SPsPar tr −

RP tm( )c

( )aaz tm − t0

( )

× exp jpg tr −RP tm

( )c

( )2{ }

exp −j2p

lRP tm

( ){ }

(3)

where λ is the wavelength of the SAR signal, aaz(·) is theazimuth envelope determined by the antenna directivitypattern, t0 is the moment when the beam centre pointing atthe scatterer, σP is the scattering coefficient of point P andSP is the amplitude of the signal determined by the powerdensity of SAR at point P.


The slant range history of point I is

RI tm( ) = SJ| | + JI| | + IS| |

=��(vtm − xJ )

2 + y2J + H − zJ( )2√

+��xJ − xI( )2+ yJ − yI

( )2+ zJ − zI( )2√

+��vtm − xI( )2+y2I + H − zI

( )2√(4)

Echo from point I is denoted by sI (tr, tm). It has a similarexpression to (3), but with a different time-delay and phaseterm determined by RI(tm). The amplitude of the signalrelies on SI, which is the power density of the jammer atpoint I.To generate the jamming echoes of the false point F, sI (tr,

tm) should be modulated according to the difference betweenRI(tm) and RP(tm) as follows

sF tr, tm( ) = GF sI tr, tm

( )∗d tr −DR tm

( )c

( ){ }

× exp −j2p

lDR tm

( ){ }(5)

where * denotes convolution, GF is the gain factor of thejammer and ΔR(tm) = RP(tm)− RI(tm). The false point F iscreated to protect the real point P, so GF should becarefully adjusted such that point P can be covered by pointF. To obtain GF, two detectors are set, one locates at pointP and the other at point J. By doing this, the power densityat these two points, denoted by SP and SJ, respectively, areobtained. Considering the jammer lies not far away frompoint I, we assume that SJ ≃ SI . Then we obtain

GF = SP/SI (6)

Therefore the scattered wave deception jamming echoes ofthe false point F is generated.

3 Analysis of jamming scope

The algorithm for scattered wave deception jamming isdesigned according to the geometry of centre points of theilluminated area and the protected area. It is accurate for thecentre, but not for other points in these areas. For anotherpoint near point I with offset (Δx, Δy, Δz), the slant rangehistory is

RFD tm( )= SJ| |+ JID

∣∣ ∣∣+ IDS∣∣ ∣∣+DR tm

( )=2

��(vtm−xP)

2+y2P+ H−zP( )2√

+��xJ −xI−Dx( )2+ yJ −yI−Dy

( )2+ zJ −zI−Dz( )2√

+��vtm−xI−Dx( )2+ yI+Dy

( )2+ H−zI−Dz( )2√

−��xJ −xI( )2+ yJ −yI

( )2+ zJ −zI( )2√

−��vtm−xI( )2+y2I + H−zI

( )2√(7)

IET Radar Sonar Navig., 2014, Vol. 8, Iss. 8, pp. 971–976doi: 10.1049/iet-rsn.2013.0341

www.ietdl.org
Note that ΔR(tm) does not vary with (Δx, Δy, Δz), so there existerrors in modulations for points except for I. The errors havean impact on the metrics of SAR imaging such as the rangeand azimuth locations, and the Doppler rate. With a pointbeing far away from the centre, errors become greater andthe fidelity of the deception jamming decreases. So theerrors of modulation limit the jamming area. The limitationsof scattered wave deception jamming are defined asthresholds for different errors below which the jammingfidelity can be guaranteed. In this section, we give adetailed discussion of the limitations of the scattered wavedeception jamming according to the different tolerance ofdifferent SAR imaging metrics.
3.1 Distortion in range

The range position where a scatterer is imaged is decided byits instantaneous slant range at tm = 0. The range position ofpoint PΔ in the image is

YPD = RPD tm( )∣∣

tm=0−RP tm( )∣∣

tm=0

= 2��xP + Dx( )2+ yP + Dy

( )2+ H − zP − Dz( )2√

− 2��x2P + y2P + H − zP

( )2√ (8)

and that of point FΔ is

YFD = RFD tm( )∣∣

tm=0−RF tm

( )∣∣tm=0

=−��x2I + y2I + H − zI

( )2√

+��xJ − xI −Dx( )2+ yJ − yI −Dy

( )2+ zJ − zI −Dz( )2√

+��xI +Dx( )2+ yI +Dy

( )2+ H − zI −Dz( )2√

−��xJ − xI( )2+ yJ − yI

( )2+ zJ − zI( )2√

(9)

The error between YPΔ and YFΔ is defined as

aD = YFD − YPD (10)

The gradient of αΔ is used to measure the non-uniformity

gradaD Dx, Dy( ) = ∂aD Dx, Dy

( )∂Dx

Dx

+ ∂aD Dx, Dy( )∂Dy

Dy (11)

If the absolute value of (11) equal to zero, no distortion willarise in range. A value equals to one means that thejamming scene may contract in a small area or expand tothe twice of the real scene, which decreases the fidelity. Sowe set 0.5 as a threshold, and a value below this thresholdis acceptable.

3.2 Distortion in azimuth

The Doppler frequency at tm = 0 determines the azimuthposition of a point in the imaging result. Taking P and PΔ,for example, θΔ is used to represent the angle between SP


and SPΔ at tm = 0. θΔ is smaller than half of the fieldangle of SAR beam. Without loss of generality, we assumeθΔ≤ 5°. Then we obtain

fdPD − fdP = − 1

l

dRPD tm( )

dtm

∣∣∣∣tm=0

−dRP tm( )

dtm

∣∣∣∣tm=0

[ ]

= 2v

lsin u0 cos uD − sin u0( )+ 2v

lsin uD cos u0

≃ 2v

lsin uD cos u0

(12)

where θ0 is the squint angle of SAR. Thus

sin uD = l

2v

fdPD − fdP( )

cos u0(13)

The azimuth position of PΔ can be expressed as

XPD = SP| | sin uDcos u0 + uD

( ) ≃ l

2v

fdPD − fdP( )

cos2 u0SP| | (14)

Small angle approximation is applied in (14), that iscos u0 cos u0 + uD

( ) ≃ cos2 u0. With a similar derivation, thedistance of a false point FΔ from F in azimuth isrepresented by XFΔ with the expression

XFD ≃ l

2v

fdFD − fdF( )

cos2 u0SP| | (15)

βΔ is defined to indicate the relative error between XFΔ

and XPΔ

bD = XFD − XPD

∣∣ ∣∣XPD

∣∣ ∣∣ (16)

Substituting (14) and (15) into (16), we obtain bD ≃ 1/2under the assumption that xp/RP tm

( )∣∣tm=0

≃ xI/RI tm( )∣∣

tm=0≃

sin u0 and xPD/RPD tm( )∣∣

tm=0≃ xID/RID tm

( )∣∣tm=0

≃ sin u0+(

uD). This means that the jamming scene will contract to thehalf of the illuminated scene in azimuth. It is caused by thegeometry of scattered wave deception jamming and isnearly a constant value for the whole area, so we do notconsider it as a limitation.

3.3 Doppler rate mismatch

Errors of the second order term of the slant range historieswill lead to the mismatching of Doppler rate. The Dopplerrate expression for point PΔ is

KPD = − 1

l

d2RPD tm( )

dt2m

∣∣∣∣∣tm=0

= − 1

l

2v2 yP + Dy( )2+ H − zP − Dz

( )2[ ]xP + Dx( )2+ yP + Dy

( )2+ H − zP − Dz( )2[ ]3/2

(17)


Fig. 2 Limitation areas of the scattered wave deception jamming

www.ietdl.org
The Doppler rate of point FΔ is
KFD =− 1

l

d2RFD tm( )

dt2m

∣∣∣∣∣tm=0

=− 1

l

v2 yI +Dy( )2+ H − zI −Dz

( )2[ ]xI +Dx( )2+ yI +Dy

( )2+ H − zI −Dz( )2[ ]3/2

⎧⎪⎨⎪⎩

−v2 y2I + H − zI

( )2[ ]x2I + y2I + H − zI

( )2[ ]3/2 + 2v2 y2P + H − zP( )2[ ]

x2P + y2P + H − zP( )2[ ]3/2

⎫⎪⎬⎪⎭

(18)

The Doppler rate error leads to defocusing in azimuth. Therelative error of Doppler rate should satisfy the followingequation to ensure a less than 20% broadening of theimpulse response width (IRW) [1]

DK = KFD − KPD

∣∣ ∣∣KPD

∣∣ ∣∣ ≤ 3

TBP(19)

where TBP is time bandwidth product.

3.4 Realisation

The scattered wave deception jamming algorithm can besummarised as a process of storing, modulating andretransmitting. If the jammer transmits the intercepted signaldirectly to the SAR without modulation, the time-delay ofthe jamming signal is RI(tm)/c. But according to (5), atime-delay of ΔR(tm)/c should be performed by the jammer.The value of ΔR(tm) must be positive, because a negativeΔR(tm) means that the jamming signal has to be transmittedbefore the time that SAR signal is intercepted, which isimpossible to realise in practical. So the following equationshould be satisfied

DR tm( ) = RP(tm)− RI (tm) ≥ 0 (20)

3.5 Scope of scattered wave deception jamming

As an instance, the parameters of scattered wave deceptionjamming are set as shown in Table 1.According to the analysis in Section 3.1–3.4, we obtain the

limitation areas inside which the errors are consideredacceptable. The limitation areas of scattered wave deceptionjamming are shown in Fig. 2.The simulated area is set from −1 to 1 km. βΔ is

approximately a constant value, so its limitation is not takeninto consideration. Area enclosed by the line with ‘○’ is the

Table 1 Parameters of scattered wave deception jamming

Variable Value Unit

H 5209 m(xP, yP, zP) (5290, 29544, 0) m(xJ, yJ, zJ) (5390, 29444, 80) m(xI, yI, zI) (5552, 29594, 0) mv 100 m/s


limitation region decided by (11), and we name it as regionI. The region enclosed by the line with ‘□’ is decided by(19), and we call it region II. The region rounded by theline with ‘Δ’ is decided by (20), which is referred to asregion III. There is no overlapping area for these threeregions. That is to say, an acceptable jamming result can behardly obtained while satisfying all the three limitations.Therefore, it is significant to make improvementsin scattered wave deception jamming to enlarge thejamming area.

4 Improved method for scattered wavedeception jamming

4.1 Region III expansion

Equation (20) limits a small region for jamming. To expand it,we have to predict the intercepted signal. Assume that theSAR does not change its transmitted pulses in differentpulse repetition intervals (PRIs), and the PRI does notchange during the whole SAR imaging process. We canalso assume that the SAR platform flies steadily duringseveral adjacent PRIs because of the inertia of the platform.Thus intercepted signals in the adjacent PRIs remainunchanged. Then, we can use the intercepted signal as aprediction of the signal for the next PRI and transmit thejamming signal by delaying a PRI. This will lead to theshift of the jamming scene in azimuth by one azimuth cell,which has little effect on SAR imaging. But by doing this,nearly a whole PRI is available for the jammingmodulation, and the jamming signal can be transmittedbefore the jammer receives the next SAR pulse. Therefore,the limitation of (20) is removed.

4.2 Shift in modulation centre

According to the deception jamming principle described inSection 2, the modulation of the false scene is performedby the scattering of the original scene on the ground. So theselection of the illuminated area always relies on the terrainnearby. The deception jamming does not make the realscene disappear, instead, it uses the false scene to cover itand weakens its scattering characteristics. So the scatteringproperties of the false scene should be stronger than that ofthe real one. If there is no strong scattering target in theilluminated area, the protected area can be hardly covered.Once the strong scattering target area is selected as the


Fig. 3 Limitation areas after the improvements Fig. 4 Azimuth cut of point scatterers

www.ietdl.org

illuminated area, the point I is also fixed. To enlarge thejamming area, we shift the modulation centre to point ICinstead of point I. IC is farther away from the SAR than I.Coordinates of IC are (xI + xC, yI + yC, zI + zC), then

RIC tm( ) = SJ| | + JIC

∣∣ ∣∣+ ICS∣∣ ∣∣ (21)

DRC tm( ) = RP tm

( )− RIC tm( )

(22)

If we directly use ΔRC(tm) to modulate the signal, the offsetsof point IC away from point I will also cause the offset of thejamming scene from the protected area. So the constantdistance between IC and I should be compensated toΔRC(tm) as follows

DR′C tm( ) = RP tm

( )− RIC tm( )+ RIC 0( ) − RI 0( ) (23)

Then we have

R′FD tm( ) = SJ| | + JID

∣∣ ∣∣+ IDS∣∣ ∣∣+ DR′

C tm( )

(24)

Substitute RFΔ(tm) in (9) and (18) with R′FD tm( )

, and setcoordinates of IC as (5490, 29244, 0) m, we obtain thelimitation areas as shown in Fig. 3.

Fig. 5 Imaging results of improved scattered wave deception jamming

a Image of the real sceneb Jamming result


After the improvements, region III is removed. Region IImoves down to share a larger common area with region I(dotted area in Fig. 3). The common area is about 125%larger than that shown in Fig. 2. This makes it possible toprotect a larger area with the jammer. In this area, errors ofDoppler rate and distortion are limited under acceptablelevels to ensure the effectiveness of jamming.

5 Simulation

Consider a point scatterer located at (0, 800). This scatterer isoutside the overlapping area of regions II and III before theimprovements, while being included after. The geometricparameters are set as shown in Table 1. The SAR transmitsa 150 MHz wideband LFM pulse at X band. The azimuthcuts of the point scatterer are shown in Fig. 4.The solid line is the azimuth cut of the real point, its IRW is

0.93 m, and the peak side lobe ratio (PSLR) is −13.28 dB.The dotted line represents the point generated by theoriginal algorithm and it cannot be well-focused. The pointusing the improved algorithm is shown by the dash line, itsIRW is 1.07 m, expanding about 15.1% comparing with thereal point. Its PSLR increases to −6.7 dB. So the algorithmproposed in this paper has a better performance thanprevious algorithms before improvement.


www.ietdl.org
A simulation for scene jamming is also presented.The area needs to be protected is the field enclosed by the
solid line. The illuminated area is selected as the town nearby.Thus the protected area can be covered by the strongerscattering town area. Considering the azimuth distortionanalysed in Section 3, the illuminated area doubles inazimuth comparing with the protected area. As shown inFig. 5b, the protected area is almost covered by thejamming scene. And the road through the jamming scenecan be seen clearly. The jamming result is satisfying.

6 Conclusion

In this work, the scheme of scattered wave deception jammingis discussed. The limitation areas are given based on theanalysis of the distortion in range and azimuth, the Dopplerrate mismatching and the realisability of the algorithm.Improvements are proposed to remove the limitation ofrealisability and enlarge the jamming area, which lead to a125% increase in jamming area than the algorithm beforeimprovements. The improvement of focusing quality isanalysed based on the simulation of point scatterer. Thesimulation of scene jamming also shows the validity of thealgorithm.

7 Acknowledgments

The authors would like to acknowledge the anonymousreviewers for their useful comments and suggestions, whichwere of great help in improving this paper. This work wassupported in part by the National Science Foundation ofChina under grant 61201283 and the NSAF under grant11176022. It was also supported by the FundamentalResearch Funds for the Central Universities under Grantsnos. K50510020004 and K5051202001.

8 References

1 Cumming, I.G., Wong, F.H.: ‘Digital processing of synthetic apertureradar data: algorithms and implementation’ (Artech House, Norwood,MA, 2005)

2 Zhang, L., Xing, M.D., Qiu, C.W., Bao, Z.: ‘Adaptive two-stepcalibration for high resolution and wide-swath SAR imaging’, IETRadar Sonar Navig., 2010, 4, (4), pp. 548–559

3 Zeng, T., Yang, W., Ding, Z., Liu, L.: ‘Advanced range migrationalgorithm for ultra-high resolution spaceborne synthetic apertureradar’, IET Radar Sonar Navig., 2013, 7, (7), pp. 764–772

4 Gao, Y., Wang, K., Liu, X.: ‘Model-based adaptive synthetic apertureradar image formation algorithm’, IET Radar Sonar Navig., 2013, 7,(2), pp. 123–129


5 Jiang, R., Zhu, D., Shen, M., Zhu, Z.: ‘Synthetic aperture radarautofocus based on projection approximation subspace tracking’, IETRadar Sonar Navig., 2012, 6, (6), pp. 465–471

6 DeLaurentis, J.: ‘Multipath synthetic aperture radar imaging’, IET RadarSonar Navig., 2011, 5, (5), pp. 561–572

7 Griffiths, L.J.: ‘Linear constraints in hot clutter cancellation’. Proc.ICASSP, Atlanta, GA, May 1996, pp. 1181–1184

8 Abramovich, Y.I., Spencer, N., Anderson, S.J.: ‘Stochastic constraintsmethod in nonstationary hot clutter cancellation – part 1:fundamentals and supervised training applications’, IEEE Trans.Aerosp. Electron. Syst., 1998, 34, (4), pp. 1271–1292

9 Abramovich, Y.I., Spencer, N., Anderson, S.J.: ‘Stochastic constraintsmethod in nonstationary hot clutter cancellation – part 2: unsupervisedtraining applications’, IEEE Trans. Aerosp. Electron. Syst., 2000, 36,(1), pp. 132–150

10 Rosenberg, L.: ‘Multichannel synthetic aperture radar’. PhD thesis, TheUniversity of Adelaide, 2007

11 Rabideau, D.J.: ‘Clutter and jammer multipath cancellation in airborneadaptive radar’, IEEE Trans. Aerosp. Electron. Syst., 2000, 36, (2),pp. 565–583

12 Techau, P.M., Guerci, J.R., Slocumb, T.H., Griffiths, L.J.: ‘Performancebounds for hot and cold clutter mitigation’, IEEE Trans. Aerosp.Electron. Syst., 1999, 34, (4), pp. 1253–1265

13 Kogon, S.M., Williams, D.B., Holder, E.J.: ‘Exploiting coherentmultipath for mainbeam jammer suppression’. IEE Proc. Radar SonarNavig., 1998, 145, (5), pp. 303–308

14 Gan, R., Wang, J., He, C., Xu, M.: ‘An improved rebound jamming toSAR’, J. Electron. Inf. Technol., 2005, 27, (2), pp. 256–258

15 Wang, W., Cai, J.: ‘A technique for jamming bi- and multistatic SARsystems’, IEEE Geosci. Remote Sens. Lett., 2007, 4, (1), pp. 80–82

16 Zheng, S., Xu, D., Jin, X., Han, H.: ‘A study on active jamming tosynthetic aperture radar’. Proc. ICCEA, Beijing, November 2004,pp. 403–406

17 Zhou, F., Sun, G., Bai, X., Bao, Z.: ‘A novel method for adaptive SARbarrage jamming suppression’, IEEE Geosci. Remote Sens. Lett., 2012,9, (2), pp. 292–296

18 Gao, X., Lei, W.: ‘Method of implementing scatter wave jamming signalto SAR’, Mod. Rad., 2006, 28, (8), pp. 22–24

19 Hu, D., Wu, Y.: ‘The scatter-wave jamming to SAR’, ACTA Electron.Sin., 2002, 30, (12), pp. 1882–1884

20 Liu, Y., Liu, Z., Dai, D., Wang, X.: ‘Analysis of jamming effect onscatter wave jamming to SAR imaging’, Chin. J. Radio Sci., 2011, 26,(2), pp. 400–405

21 Gan, R., Wang, J., He, C.: ‘Performance of jamming to SAR by reboundmode’, Signal Process., 2003, 19, (z1), pp. 382–385

22 Li, T., Chen, W., Lu, G., Wang, D.: ‘A study on scatter-wave jammingfor countering SAR’. ICMMT, Beijing, China, April 2007, pp. 1–4

23 Tian, X., Fang, G.: ‘Study on scatter wave deceptive jamming tospaceborne SAR’, Control Autom., 2009, 25, (10), pp. 224–225

24 Wang, D., Wang, E., Lei, W.: ‘Generation and real-time require ofdeceive jamming signal against SAR’, Aerosp. Electron. Warf., 2007,23, (1), pp. 30–33

25 Sun, G., Zhou, F., Xing, M., Bao, Z.: ‘Deception-jamming technologyagainst SAR based on deceptive scene and real-time analyses’,J. Xidian Univ., 2009, 36, (5), pp. 813–818

26 Zhao, B., Yang, J., Sun, G., Zhou, F., Bao, Z.: ‘A method of SAR fastrepeater deception jamming for large false scene’, J. Electron. Inf.Technol., 2012, 34, (4), pp. 963–968

27 Zhang, Y., Wang, J.: ‘Research on rebound jamming against biSAR’,J. Electron. Inf. Technol., 2007, 29, (5), pp. 1061–1064


Documents

Improved method for synthetic aperture radar scattered wave deception jamming