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Inverse Synthetic Aperture Radar Simulators as Software defined Countermeasure Systems Security by Obfuscation and Dece

Modelling Sirthe human element The executiof this project is shown in Figure 1 in a visualFriendly Asset(Self Protection Mode)Decoy Platform(Stand-off Protection ModeSignal Detection SubsystemDown-convert(Threat Signal)entify threatke decisions based on the threat particularProduce appropriate countermeasure produEnhance the reality factor of the countermeasuretaking into consideration the limitations of theoperator loop process that the countermeasure productis a real encoand not a false targetP-convFig

1 Visual executive summary of the proje

se Synthetic Aperture Radar Simulators as Software-defined Countescattering modelling is affected by theThe ps mputing moving force that proceeds the points on the ship in time to new locations fromeir initial values depending on the motion of the ship

The meis performed by anfine tranmodule that prool, yaw, pitch and translations fundhe processions actions are placed into the context of a three-dimensional environmenFig 8 Synthetic Environment Modelling

And the graphical representation of the inverse scattering is shown in Figure 9Resolution Cells Inclusion for ISAR Calculations2g 9

Theoretical implementation( Polar Format Approrelationships among the entities are identified in this dease It is ensured that allonstraints and boundary conditionscontext alperational and functional requirements are taken into consideration, as shown in Figure 10

se Synthetic Aperture Radar Simulators as Software-defined Counteecurity by obfuscation and Deception for Electronic Computer Networks Warfare③②②DHFig 10 Entity Relationship(E-R)identificationlementation ProcedureThe implementation procedure follows the rules of a complex system

In other words mndividual components or transfer functions of the simulator when combined give a uniquee of the system beforns when alput together in a graph Each individual point cannottop view images or side view images of the target This decision depends41 Computing MethodologyThe set of methods that define the processes and the order of this project is to be achieved is

Target Input DataSAR DSP Blockphase informationoute 1: Conventional simalator approachSAR Imaging outputroduces ISAR ImagFigure TypFigure TypeDisp ars the correspondingnumbeonwarder to later stageFig

11 Computing MethodologyThe simulator software implementation followed the process oriented technique as shown12

se Synthetic Aperture Radar Simulators as Software-defined CounteFig 12 Simulator Implementation of the FB-14 modular software systemefined radar system

The system designeasily verified, validatedWe thenthe resultstained from our effort5 Simulation ResultsScience Technology Thereed function theffects to the outputin order to increase the validity of the output whichat the measurementScience Technology Journal of the Institute of Physicspresented at NATO SET-136 Specialist's Meeting on Software Defined RadInvoking the single layer model whichperstructure3 is created

ellingFig 13 Single Layer Slant Range Profile and corresponding ISAR imageFig 14

Multiple Layer Slant Range Profile and corresponding ISAR imagyMilitary targets are different from civilian targets in the fact that there arehighcenters othe IsAR image accordingssify or even identify a radar contact Our simulator can produce such effects as shown ingure 15 Outputs of twother are shown in order to demonstrate how different the image can be even when the

se Synthetic Aperture Radar Simulators as Software-defined CounteWWFig 15 ISAR Shortcomings Effect using the Single Layer Model

3 Angular Glint Results Issues for Military Targetsder to increase the validity of the simulator output to the adversary radault is inspired by [Skolnik, 2001] andint effect in a threedimensional synthetic environment with respect to the real target points We call thismponent Glint Effect in 3D at the target and is shown in Figure 15(a)

se Synthetic Aperture Radar Simulators as Software-defined Counteecurity by obfuscation and Deception for Electronic Computer Networks WarfareIn this chapter we will create a virtual environment that is considered to accept as inputs thet-in-time characteristics of a threat signal, pass them through a transfer function which isa simulator system and then produce false target images that are realistic becaey abideue that since coherent countermeasures are different fromturised sensors are involved needs to be reinvented Here the literatuted for isar simulators and coherent countermeasures becausecontribution ise amalgamation of these two fields In section 3 we apply the concepts of conceptualtion procedure, in the fthe computing methodoled the finalentation The results of this worlbe foundection 5 Here the simulator is proven to be able to produce ISAr images affected by highereffectivity on lower coordinates and angular glint effects which isgets Also we argue that the compuethodology can be reused inthe domain of computer networks warfare by presenting the dual problem spactheprojects factor by ascertaining the ability of the current effort to be able to implementel finally in section 6marks are given and we also make a recommendation for future work by suggesting thatthe simulator should beth the use of concepts from the field of parallelprogramming in order to increase its execution speed2 Coherent Countermeasures foDefence at Sea ISAR SimulatorsDistance is an integral factor in countermeasure activities When the decoy signalproduced on-board the friendly asset it is called self-protectid when it is produced offboard it is called stand-off protection [Hill, 1988

The large volume and weight of thecountermeasure technology up to the 1990s demanded solutions of self-protection Standthe threat signal or chaff systems, that is low valuethat would attract thefrom its target because thesection than theotected platform For the above reasons conventional radar countermeasure techniquesfell into two major categories: angle deception and range deception In the first case aGain Jamming With this methening function is performed bransmitting replicas of the adversary signal back to the hostwhen the illuminating signal is weak andther evens out the phases or oensates the sensor producing either way the deception effect With the second methodle is Range gate Pull-Off(RGPO) The hostile radar concentrates on the target byplacing a range gate of a few hundred meters around the target Because it no longerbreaks the lock by making the hostile radar lose this gate thus producing the deceptionfect both methoentionalsystems and will not deceive a high[Wiegand, 1991] Both abovonventional radar tracking systems, like the monopulse method But they are not efficwhen the target is viewed by a high range resolution system in stand-off mode or when the

Modelling Sirmissile platform is equipped with a miniaturized highherefore the problem ofneeds to be re-invented for theread fodirect ISAR countermeasures that would oppose a miniaturized high range resolution radarReview of the state of the artventional Isardeception techniques in order to be able to draw comparisons and build the foundations of211 ISAR Simulatorsarlier studies by (shillington et al, 1991 have described a technique used to simulate ISArages of a ship model while under angular motions such as yaw, Pitch and roll [Porter efal1994tion of information resulting fromhe point spread function Also foundatlaid towards the studyterference effects(glint) [Haywood et al, 1994] have introduced the ISARLAB software package wehensive set of functions that emulate the particular functions of an ISARAnd [Emir et al, 1997] have developed a simulation program which can generate ISARlicatiovaluating the perfofship classifieecent studies by Isented the mathematical basis of theAperturss

[Ling et al, 2006] have investigated the acquisition ofide view IsAr images with the proper cross range scaling The technique is based on theheasurement off the two main feature lines of thed the stern

line Thishas the advantadegradations effect of specular multipath effects on the final image [Rice et al, 2006 haescribed a method of isarassification basedexisting three dimensional ship refof ISAR images in order to estimate the dominant ship motion In all above indicative workk makes anof the computing force that provides the motion of the radar and targetattempt to fill in the details of an ISAR simulation analysis in a virtualreality ensoftware defined radar systemulator in the context of a software defined radar system falls under the cohererwhich must have features nearly identical to the real ship target And in order to enscorrect geometry and realistic false target velocities there is a need to take into account anentirely algorithmically The purpose of the research is to obscure the real target into a cloud

se Synthetic Aperture Radar Simulators as Software-defined CounteScation and Deception for Electronic Computer Networks Warfareof other plausible yet false targets as stated by [Rui] The analysis in[Xiaohan] states that theke target mask, whichnly coordinatesIntensIties,storedadvance and that the Doppler s slope is important in the deception imaging process becausehelps the threat signal to focus on the false target We asimulations Further false target geometry explanations can be foundngbing, 2007] where a geometry and signal model is presented For an ASIC (applicationted circuit) approach [ Fouts et al 2005 have implemented the firstdocumented hardware-based complete false target generator system Nevertheless the exacttents of the look-up table that synthesizes the target are not fully discu3 Conceptual Modelling for Coherent Countermeasureshe fact that an isar simulator can be used as a software- defextendedby an airborne high range resolution seLKostis et al, 2005; Kostis etaccommoddded value which is a glint effects generator [Kostis EUSAR, 2008stis et al, PCI2007 For ISAR countermeasures piects in the digital signal processing process the simulator can now produce more realisticesults (Kostis, 2008]

This added value is necessary in order to add realistic effects to theg angular glintting vector and phase gradient The first method is discussed in[ Chen] where glint is calculated by the doof the poynting vector and the headingector The second method is discussed in [Ming) where and Ros(radar cross sectiopensation method is presented For our purposes we have used the approachesund in [Schleher] and [Shirman] where they base thetimation on the transversalomponent of the interconnecting vector between the two interfering sorstems the research question of how useful, economic and straightperform electronic warfare functions In this section we present the conceptual modellingsteps of the simulator And in the next section we present the results that bear the prooWe aradar) sensors that are capable of resolving the ship target in slant, cross and even heigranges while always tracking their most prominent points Releffective soft-killnethods, whiedeceive rather than destroy, is the capture of the threat signaltal radio frequency memory, its down-conversion, its injection with false targeteffectivity data by digital signal processing means, its up-conversion and finalansmission to the threat sensor [Neri, 2007he provisionse Synthetic Aperwhichberate realistic false target effects by adding glint noiseThe threat signal alwaysas it is an inherent characteristic of an extended target

Modelling Sir31 Application Domain DefinitionThe task of Application DorDefinition is given to the smes that have authoritativeion about the actual situational context Usually at this point in time the SMEs willth the SEs and discuss the theoretical and practical milestones thathave to be observed during the course of the project Usually at this stage the SEs will hayonly superficial knowledge about the subject matter On the other hand SEs thatperfotask of smEs are valuableicular situation We now explain theational abilities of High Range Resoeoretical background The main theoreticalfor ISAR imaging are inlogical progression: SAR imaging, spotlight mode of SAR imaging leading to ISARA SAR system has an antenna aperture which is synthesised by the combination of relatableparts rather than the real dimensions of its physical antenna The SAR imaging principle isCoherenceSampling

The digitisation of continuousses The synthetic arnumerIcste all thein mathematical terms Startingantenna aperture of 3 meters looking down totarget 10 Km away, therange resolution is0030000=100mThis azimuth resolution is very low because a single resolution cell is illuminatedme, For example two ships less than 100 meters apart at the same range would appear asne echo thus t'ed by the radar of Figure 2Fig 2 Conventional Radar Angular Resolution or Real Aperture Radar(RARow assuming stationary targets and employing an airborne SAR system at the samfrequency and range the azimuth resolution Ax can be brought from 100 meters down to 3in Fi

se Synthetic Aperture Radar Simulators as Software-defined Counteecurity by obfuscation and Deception for Electronic Computer Networks Warfareg 3

Synthetic Aperture Radar (SAr)The fly time should equal the distance of3d3*3△x=3R→Rborne synthetic aperture systenthe target thth resolution becomes much finer at only 3 meters longWhen the radar beam is focused on one point in space the concept is call Spotlight SyntheticAperture Radar, as shown in Figure 4RadaSensord=depression angle(x1y1a=aspect angleSea LevelShiTargetFig 4 Spotlight Synthetic Aperture RadarSpotlight SAR is the dual of the Inverse Synthetic Aperture Radar concept that will be usedthat synthesizes the extended antenna aperture that leads to the higher resolution mage

In order to create false targets an introductory procedure is shown in Figure 5 [ Kostis et al,OP MST 20095 The position of the False Target Generator SubsystemCare must be given to the False Target Generator subsystem Its outcome must resemble aother words the reality fis decided by the ability of the false target generatsystem3

2 Problem Space DecompositThe entities and prethat must be rerplishment ofthe simulation are defined For this project the list of entities as shown in TableSimulationI RealityTarget physical propertiesnherent amplitude &inge cartesian ship for this project But it could be in the sternordinates withbow of the shiprespect to theFM height finder radar (altimeter)on airbornem radar to target5 Aspect angle fromChange of aspect angleadar to targetton

se Synthetic Aperture Radar Simulators as Software-defined Countecation and Deception for EComputer Networks Warfare6 Glint EffectsPhysical PhenomenonTarget movement due to forces of natureSlant Range Profile and ISAR Image of targetTable 1

entitiee can draw the necesns between the entities and come up with thecorresponding processes, as shA gain as above the compebetween thereality and the simulation is strongly taken into accoursical presence and movement of targehe pace encoordinates to theB Provide information to Physical presence and movement of radarthe Pace Engine oflantc Provide information to Measurement-captures reality with a serrange)dimensionalnformation to Instrumentalthe ISAR Processorbout the radarsct angle variation Caused by changeadar locationConditioning(Masking)Caused by changerotateddatabasHRecording Process-processes history of targetDatabase to ISamputer memoryr Processingtranslates reality to computerTable 2 processes

elling33 Entity Abstraction DegreeThe representational abstraction of the involvednalized in this step

The levelccuracy, precision, resolution and fidelity of the entities and processes is determined Theat an aspect angle of forty-five degrees First the extended naval target is modelled asisotropic or directive point scatterers model, as shown in Figure 6 [Kostis et al, I]SSST 2009wrck Refectance MapThen the false target is synthesised by taking the reflectivity grouping of multiple layers7, where another lat