Single frequency pulse, linear frequency pulse, and stepped frequency pulse are a few of the radar pulse waveforms used to obtain target range information. Using a basic single frequency pulse limits the radar's range resolution by the pulse width, has excessive energy requirements, and is more vulnerable to jamming. With the use of frequency modulation the radar's range resolution can be greatly enhanced. This report deals with some of the issues involved in using stepped frequency pulse trains to obtain high resolution target range and range autocorrelation profiles. Radar returns from stepped frequency pulse trains may be coherently processed to obtain the range profile, or noncoherently processed to obtain the range autocorrelation (or separation) profile. The inverse discrete Fourier transform (DFT-1) of N coherently detected pulse returns from each range cell (where N is the number of pulses in the train) gives the high resolution range profile within that range cell. The DFT of the squared magnitudes of the pulse returns yields the autocorrelation of the range profile (the separation profile). Range resolution is determined by the total bandwidth of the pulse train. Using a Fast Fourier Transform (FFT) algorithm for the DFT a simulation of the radar system is implemented on the University of Central Florida, College of Engineering Research VAX 11/750 computer. This simulation computes and plots the range and separation profiles.

[pt] Este trabalho especifica um Sistema de Simulação Radar desenvolvido na linguagem de programação C, tendo como aplicação a área militar. Visa a análise, simulação, monitoração e avaliação de sinais na interação de Sistemas Radar e Sistemas de Contra Medidas Eletrônicas (CME). A flexibilidade e a modularidade do Sistema de Simulação Radar proposto objetivam a descrição realista do comportamento de diversos radares modernos. A escolha correta da forma de onda e a definição do modelo de radar mais adequado a uma determinada aplicação são considerados fatores essenciais para a utilização eficaz do Sistema de Simulação proposto. Como abordagem preliminar à implementação do Sistema de Simulação, o presente trabalho apresenta um estudo das formas de onda de radar e de alguns radares modernos de maior interesse. / [en] A Radar Simulation System hás been developed on the C programming Language. Its application is addressed to the military fiels and deals with the analysys, simulation, monitoring, and evaluation of signals in the interaction of Radar and eletronic Counter Measure Systems (ECM). The flexibilitu and modularity of the proposed Radar Simulation System is aimed at the realistic description of the behavior of many modern radars. The choice of the radar waveform and the definition of the appropriated radar model to a specific application are considered essential factors to an effective utilization of the proposed Radar Simulation System. Radar waveforms and modern radars considered of great interest have been presented as an introductory approach to the implementation of the Radar Simulation System.

This document describes radar propagation modelling using split step parabolic wave equation (PWE) method. A computer program using Fourier split-step (FSS) marching technique is developed for predicting the electromagnetic wave propagation in troposphere. The program allows specification of frequency, polarization, antenna radiation pattern, antenna altitude, elevation angle and terrain profile. Both staircase terrain modelling and conformal mapping are used to model the irregular terrain. Mixed Fourier transform is used to implement the impedance boundary conditions. The conditions and the limits of different approximations are stated. The propagation code, RPPT (Radar Propagation Prediction Tool) is developed in Matlab 6.0 with a user friendly GUI. Different PWE methods can be selected in RPPT for different applications. The results are presented as one-way propagation factor and path loss in decibels versus range.Comparisons are made between different PWE techniques and other propagation models to demonstrate the ability and accuracy of the present model to accommodate various situations. It is assumed that the reader is familiar with the tropospheric propagation.

Thesis (MSc (Mathematical Sciences. Applied Mathematics))--University of Stellenbosch, 2006. / In this work we present a novel method to do measurement correlation between target observations made by two ormore radar systems. Some of the most common radar sensors available are those measuring only range (distance to the target) and bearing (azimuth angle). We use these measurements to determine the correlation between two di¤erent sensors observing the same target. As a by-product of the correlation algorithm, we nd a way to estimate the target height for a target observed by at least two radar sensors. The correlation method is expounded upon, where we discuss measurement correlation for moving targets. Targets are tracked using a Kalman Filter, and correlation is done between new observations and existing target tracks. Finally, the correlation algorithm is implemented in an interactive 3D computer simulation. Results obtained indicate a high success rate, with false correlations only obtained where sensor accuracy is the limiting factor.

Game engines are well known for their use in the gaming industry but are starting to have an impact in other areas as well. Architecture, automotive, and the defence industry are today using these engines to visualise and, to some extent, test their products. In this thesis, we have examined how the game engine Unity could be used for simulating a radar with the purpose of detecting and measuring sea clutter. Following a pre-study examining different implementation approaches, it was decided to use ray tracing. The radar itself is simulated by using the camera to emit rays and having a plane object directly behind it act as a receiver. Rays are then individually traced for each pixel, propagating throughout the scene and saving information such as hit coordinates, distance travelled, and direction. By using the total travel distance of each ray that returned to the receiver, the phase of each ray is calculated. This is then used to compute the total amplitude, which represents the returned signal strength. Using a compute shader, most of the computations are done in parallel on the GPU, enabling millions of rays to be traced. As measuring sea clutter was an objective of the study, tests measuring the ocean were carried out. These used ocean surfaces with two different sea states, using the Phillips spectrum to generate realistic waves. A ship object was then tested in free space and on two different ocean surfaces. The calculated amplitude and the number of rays returned were used to determine the signal strength returned and the RCS of the object. The purpose of this was to compare with other results of sea clutter studied, observed both in the real world and in simulated scenarios, and determine if our approach could be a valid choice for the industry. Some results matched the findings of a similar study that used a professional radar simulation tool called OKTAL. Other results of sea clutter were found to not be realistic due to certain limitations. The current main limitation of our implementation is not being able to trace a large enough ocean surface with the finer details needed for realistic results. However, this could be solved by creating a better implementation. These findings suggest that simulating radar and sea clutter in Unity is a feasible approach worth continuing to explore. / Spelmotorer är välkända för sin användning inom spelindustrin men har också fått genomslag inom andra områden. Arkitektur, fordonsindustrin och försvarsindustrin använder idag dessa verktyg för att visualisera och till viss mån, även testa sina produkter. I detta examensarbete har vi undersökt hur spelmotorn Unity kan användas för att simulera en radar i syfte att detektera och mäta sjöklotter. Efter en förstudie där olika implementeringsmetoder undersöktes, beslutades det att använda strålspårning (eng. ray tracing). Själva radarn simuleras genom att använda kameraobjektet i Unity för att sända ut strålar. Bakom kameran finns ett planobjekt som fungerar som mottagare. Strålar spåras sedan individuellt för varje pixel och sprider sig genom en given scen. Samtidigt sparas information såsom träffkoordinater, den totala färdsträckan samt riktning. Genom att använda det totala färdavståndet för varje stråle som återvänt till mottagaren kan fasen för varje stråle beräknas. Detta kan sedan användas för att beräkna den totala returnerade amplituden, vilket motsvarar den returnerade signalstyrkan. Med hjälp av en "compute shader" kan databeräkningarna göras parallellt av GPU:n vilket underlättar när så många strålar ska spåras. Eftersom syftet med uppsatsen var mätning av simulerat sjöklotter, genomfördes tester för att mäta på ett simulerat hav. Havsytorna hade två olika sjöstadier, vilka genererades med Phillips-spektrumet för att få realistiska vågor. Ett fartygsobjekt testades sedan i frirymd och sedan även i de två olika havsytorna. Amplituden och mängden strålar som returnerades användes för att bestämma den totala returnerade signalstyrkan och "Radar Cross Section" (RCS) för objektet. Syftet med detta var att kunna jämföra med andra studier gällande sjöklotter, både simulerade som verklighetsbaserade och avgöra om vårt tillvägagångssätt kunde resultera i ett användbart verktyg för branschen. De olika amplituder och antalet strålar som vi fick tillbaka varierade beroende på vilka vinklar och havsytor som användes.Vissa resultat var inte realistiska jämfört med verkliga mätningar av sjöklotter. Det beror främst på våra nuvarande begränsningar i att inte kunna spåra en tillräckligt stor och tillräckligt detaljerad havsyta, vilket behövs för att mätningarna ska vara mer realistiska. Däremot matchade vi några resultat med de från en liknande studie, där verktyget OKTAL, som är ett professionellt radarsimuleringsverktyg, användes. Detta i kombination med möjligheterna för en förbättrad implementation tyder på att användningen av en spelmotor som Unity är ett intressant verktyg värd att vidareutforska radarsimuleringar med.