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As objects move, their changing shape produces a signature that can be measured by a radar system. That signature is called the micro-Doppler signature. The micro-Doppler signature of an object is a distinguishing characteristic for certain classes of objects. In this thesis features are extracted from the micro-Doppler signature and are used to classify objects. The scope of the objects is limited to humans walking and traveling vehicles. The micro-Doppler features are able to distinguish the two classes of objects. With a sufficient amount of training data, the micro-Doppler features may be used with learning algorithms to predict unknown objects detected by the radar with high accuracy.

La hipótesis principal del estudio es que la morfología del ovario poliquístico (MOPQ) es una marcador precoz del síndrome del ovario poliquístico (SOPQ) ya en la adolescencia. Para ello se ha diseñado un estudio descriptivo y prospectivo comparando la prevalencia de MOPQ en dos grupos de adolescentes con riesgo diferente de presentar SOPQ en la edad adulta: adolescentes sanas y adolescentes con antecedente de pubarquia precoz (PP). En la actualidad se sabe que un 50% de las adolescentes con antecedente de PP desarrollarán a partir de la menarquia el SOPQ Las hipótesis secundarias han sido: un mayor peso al nacimiento (PN) se correlaciona con mayor frecuencia de MOPQ. Y la hormona antimulleriana (AMH) es un marcador de MOPQ. La MOPQ se define según los criterios del 2003 de Balen: uno o dos de los ovarios tienen un volumen mayor a 10cc y/o ≥12 folículos. Se han aplicado estos criterios utilizando la ecografía bidimensional (2D) y la tridimensional (3D), usando en este caso el sistema VOCAL-delineación manual. También se ha estudiado la vascularización con el Doppler espectral y el power Doppler tridimensional, ya que clásicamente se ha considerado que el ovario con MOPQ está más vascularizado. Se han reclutado 21 adolescentes con PP y 41 sanas. Los dos grupos presentan una edad de la menarquia, un peso al nacimiento y un IMC similar. La prevalencia de MOPQ en adolescentes con historia de PP es similar a la de la población sin PP: 28,6% vs 17,1% respectivamente, cuando se explora con ecografía bidimensional; 52,4% vs 41,5% respectivamente, cuando se explora con ecografía tridimensional. No hay diferencias en el PN entre las adolescentes con y sin MOPQ (diagnosticada con ecografía bidimensional o tridimensional). Cuando la MOPQ se diagnostica con la ecografía bidimensional, los niveles de hormona antimulleriana son similares entre las adolescentes con y sin MOPQ. Sin embargo, cuando la MOPQ se diagnostica con ecografía tridimensional, los niveles de hormona antimulleriana son más elevados en el grupo de adolescentes con morfología de ovario poliquístico. Se han comparado los resultados obtenidos con la ecografía bidimensional y tridimensional. El volumen ovárico de las adolescentes medido con ecografía tridimensional es mayor que cuando se mide con ecografía bidimensional En las adolescentes con PP existe una correlación lineal directa entre el volumen ovárico medido con ecografía bidimensional y el peso al nacimiento. No existen diferencias en la vascularización ovárica (medida con Doppler bidimensional o tridimensional) entre las adolescentes con y sin PP. Tampoco existen diferencias en la vascularización ovárica (medida con Doppler bidimensional o tridimensional) entre las adolescentes con y sin MOPQ. / The main hypothesis is that polycystic ovarian morphology (POM) is an early marker of polycystic ovary syndrome (POS) in adolescence. It has been designed a prospective descriptive study comparing the prevalence of POM into two groups of adolescents with different risk in presenting POS in adulthood: healthy adolescents and adolescents with a history of precocious pubarche (PP). Today we know that 50% of adolescents with a history of PP will develop POS. The secondary hypotheses are: a higher birth weight (BW) correlates with increased frequency of POM. And Antimullerian Hormone (AMH) is a marker of POM. The POM is defined by the criteria of Balen, 2003: one or two of the ovaries have a volume greater than 10cc and / or ≥ 12 follicles. It has been applied these criteria using two-dimensional (2D) and three-dimensional (3D) ultrasound, using in this case the VOCAL system-manual-delineation. Increased ovarian stromal blood flow has been considered to be a parameter to assist in the ultrasound diagnosis of POM. We have studied the ovarian stromal blood flow with the color Doppler and with the three-dimensional power Doppler imaging. It has been recruited 21 adolescents with PP and 41 healthy subjects. The two groups have similar age at menarche, birth weight and body mass index. POM prevalence in adolescents with a history of PP is similar to that of the population without PP: 28.6% vs. 17.1% respectively, with 2D ultrasound, 52.4% vs 41.5% respectively, with 3D ultrasound. No differences are found in BW among adolescents with and without POM. When POM is diagnosed by B-scan, AMH levels are similar between adolescents with and without POM. However, when POM is diagnosed by 3D ultrasound, AMH levels are higher in adolescents with POM. Ovarian volume measured by three-dimensional ultrasound is higher than when measured by two-dimensional ultrasound. There are no differences in ovarian vascularization (measured by two-dimensional color Doppler or three-dimensional power Doppler) among adolescents with and without PP. There are no differences in ovarian vascularization (measured by two-dimensional color Doppler or three-dimensional power Doppler) among adolescents with and without POM.

Pulsed ultrasound Doppler velocimetry proved to be capable of measuring velocities accurately (relative error less than 0.5 percent). In this research, the limitations of the method are investigated when measuring: in channels with a small thickness compared to the transducer diameter, at low velocities and in the presence of a flow reversal area. A review of the fundamentals of pulsed ultrasound Doppler velocimetry reveals that the accuracy of the measured velocity field mainly depends on the shape of the acoustic beam through the flow field and the intensity of the echo from the incident particles where the velocity is being measured. The ultrasonic transducer turned out to be most critical component of the system. Fundamental limitations of the method are identified. With ultrasonic beam measurements, the beam shape and echo intensity is further investigated. In general, the shape of the ultrasonic beam varies depending on the frequency and diameter of the emitter as well as the characteristics of the acoustic interface that the beam encounters. Moreover, the most promising transducer to measure velocity profiles in small channels is identified. Since the application of pulsed ultrasound Doppler velocimetry often involves the propagation of the ultrasonic burst through Plexiglas, the effect of Plexiglas walls on the measured velocity profile is analyzed and quantified in detail. The transducers ringing effect and the saturation region caused by highly absorbing acoustic interfaces are identified as limitations of the method. By comparing measurement results in the small rectangular channel to numerically calculated results, further limitations of the method are identified. It was not possible to determine velocities correctly throughout the whole channel at low flow rates, in small geometries and in the flow separation region. A discrepancy between the maximum measured velocity, velocity profile perturbations and incorrect velocity determination at the far channel wall were main shortcomings. Measurement results are improved by changes in the Doppler angle, the flow rate and the particle concentration. Suggestions to enhance the measurement system, especially its spatial resolution, and to further investigate acoustic wave interactions are made.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / A simplex or ‘passive’ continuous wave and monopulse seeker tracks specific attributes of a target’s radio frequency (RF) radar return in some coordinate frame. In particular, a return carries dynamic information in amplitude (ω) and frequency (ω) at some point in azimuth (r,θ) and elevation (r,θ) planes. A passive seeker requires an illuminator beam, I(ω,φ,θ), and may require a frequency modulation on the illuminator. To model a simplex target return, we have based the dynamics on a point source radar cross section (RCS) along a line of sight (LoS) radial. The Az and El angles are equivalent to antenna placement, the attenuation and frequency dynamics are modeled in commercial off-the-shelf (COTS) software.

This thesis is based on a paper by V. Issakov, presented 2009, where a circuit of a merged power amplifier mixer solution was demonstrated. This work takes that solution and simplifies it for the use at a lower frequency. The implementation target is a Doppler radar application in CMOS that can detect humans in a range of 5 to 15 meters. This could be used as a burglar alarm or an automatic light switch. The report will present the background of Issakov’s work, basic theory used and the implementation of the final design. Simulations will show that the solution presented work, with a 15 dB conversion loss. This design performs well compared to reference mixers. With this report it will be shown that it is possible to make a simple and compact Doppler radar system in CMOS. / Denna avhandling bygger på en artikel av V. Issakov, presenterad 2009, där en lösning för att sammanslå en effektförstärkare med en mixer till en krets visades. Detta arbete tar denna lösning och förenklar det för användning vid en lägre frekvens. Målet är att implementera en dopplerradar i CMOS som kan detektera människor inom ett avstånd på 5 till 15 meter. Denna radar skulle kunna användas som ett inbrottslarm eller en automatisk strömbrytare. Rapporten kommer att presentera bakgrunden från Issakov’s arbete, grundläggande teori som används och genomförandet av det slutliga kretsschemat. Simuleringar visar att den presenterade lösningen fungerar, med en 15 dB konverteringsförlust. Denna konstruktion presterar väl jämfört med referens mixrar. Med denna rapport visas det att det är möjligt att göra ett enkelt och kompakt dopplerradarsystem i CMOS.

This thesis contributes to knowledge by describing two novel methods to calculate 3D blood velocity and flow within the heart using 3D colour Doppler images. The principal goal of both methods was to overcome the main limitation of Doppler systems which is that the Doppler effect only measures one component of the velocity (parallel to the beam direction). For that reason, measured velocity and calculated flow depend on the angle between the beam direction and the flow. The first method was developed to reconstruct 3D intracardiac velocity vector fields. This is the first time that such vector fields have been obtained from 3D colour Doppler images. The novelty of the proposal lies not only in the 3D velocity reconstruction, but also 1) a new noise model for colour Doppler images was proposed which improves the realism of simulation studies, 2) an efficient patch-wise implementation was introduced and 3) ventricle wall motion was used to enable full ventricular coverage. Based on simulations minimum acquisition requirements for accurate reconstruction were established. These requirements were: view angles over 20 degrees and noise below 10% of the Doppler maximum velocity. The method was tested on healthy volunteers and on paediatric patients and an accuracy of 15% compared to flow Magnetic Resonance Imaging (MRI) was obtained, when acquisition and data conditions were close to the optimum range. The second method proposes an algorithm to calculate angle-independent flow rates through surfaces within the heart and vessels. Built on the Gauss’s theorem, this method enables to increase coverage beyond the Field of View (FoV) of individual colour Doppler images by combining images acquired from multiple views. The method was validated in patients with Hypoplastic Left Heart Syndrome. Results were compared with the current clinical gold standard measurement of flow MRI, agreeing on flow values and volumes to less than 10%. The novel methods proposed in this thesis have shown encouraging results using volunteer and patient data. I hope that the methods proposed will in the future be able to offer advanced flow measurements using echo. The ability to improve the information available from echo imaging, due to its ease of use and cost effective nature, has the potential for widespread improvements in clinical care.

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / This paper describes the application software used to convert AIM-120A, Advanced Medium Range Air-to-Air Missile (AMRAAM), telemetry data to a series of color images and time-correlated engineering unit results. X Window System-based graphics facilitate visualization of the doppler radar data. These software programs were developed for the VAX/VMS and DEC Alpha environments.

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