Mobile Phone, without this we can’t think to pass a day in presence. We have found a rapid increase of mobile phone users from a few years ago till now. Day by day the modern technologies allow the mobile phone to become smaller, cheaper, and more reliable. This also creates new possibilities for applications and integrations of the classical broadcast systems and modern mobile phone technologies. One example is the FM transmitter in mobile phone. The FM transmitter in a mobile phone is a “cool” feature which allows listening to the music content in phone on a car or home radio.   This thesis work deals with the near field characterization of FM transmitters in mobile phone applications. The RF scientists and engineers neglect the near field zone because typical RF links operate at distances of many wavelengths away where near field effects are totally insignificant. But in this work we are interested in the near field properties of the FM transmitter. We measured the field intensity at near field and estimated the field strength at the far field region at 3 meters. To measure the field intensity and the effective radiated power we used HR1 near field scanner. As this is a new measurement approach, we made the validation of this system by measuring a reference dipole antenna at 880MHz and then compare the measured results to the CST simulation results. A basic phone model of FM transmitter has been created by CST simulation and a prototype has been made which was also used as our DUT. After validation of the near field measurement system we measured our DUTs (3 models-one cable fed prototype and two active devices) with the near field system and estimate the effective radiated power and field intensity at 3 meter. Furthermore, we measured our DUTs at 3 meter with a far field measurement system with optical fiber connection. A feasible relation between field strength and measured power was defined in order to correlate the near field scanner results with the far field measurement system.   This paper also provides a short design guide line for built in FM antennas by relating the antenna size and placement to input power and the field strength in mobile phone FM transmitter application

In the literatures of investigating the coupling mechanism between laser diodes and fibers, Gaussian beam profile was used to describe the propagation of laser beams. But the real laser diode beams exist astigmatism. In order to understand the distributions of real laser diode beams, we used single-mode fiber interferometer to measure the near-field intensity and phase distributions of laser diodes. The nanometer aperture of taper fiber was used to scan through the horizontal and vertical directions across the maximal intensity point of the planes which were perpendicular to propagation axis to measure the intensity and phase distributions of laser diodes. In the measurement of phase distributions, these two single-mode fibers produced interference fringes through accepting laser beams. When the taper fiber scanned the optical field and the reference fiber kept a fixed distance from a laser diode for a stationary phase, the interference fringes shifted because of the phase difference of laser diodes change. In the measurement, in order to improve the stability of interference fringes and consider the aperture of taper fiber, we altered some experiment frameworks. There were four types of experimental framework. According to the experiment results of the near-field measurements, the measured beam widths along the horizontal and vertical directions at the laser diode facet were 4.11 £gm and 1.57 £gm respectively. The measured wavefront radius curvature were 6.59 £gm and 2.96 £gm in horizontal axis and vertical axis respectively. After Gaussian beam fitting, the beam widths along the horizontal and vertical directions at the laser diode facet were 4.04 £gm and 0.83 £gm respectively. The difference in beam widths between measured values and Gaussian fitting were 0.07 £gm and 0.74 £gm. The measured beam widths and the Gaussian beam curve fitting had similar results. We could see that the beam spread tendency in the z-axis for the laser beam which propagated in the z direction. In the phase distribution measurement, the measured wavefront radius curvatures and the theoretically calculated Gaussian beam values had a slight difference. The calculated wavefront radius curvatures at the laser diode facet were 11921.51 £gm and 3.48 £gm in horizontal axis and vertical axis respectively. They were 1809 times and 1.2 times of the measured values. The aperture of taper fiber was expanded because of the energy of laser beams, which also caused the spatial resolution degeneration. Moreover, the wavefront radius curvature in horizontal direction was biggish so the measurement framework also limited the ability of the phase distribution measurement. The above points were the reasons to cause the error of the phase distribution measurement. Furthermore, the measurement of the laser diode facet is under investigation.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21366号 / 工博第4525号 / 新制||工||1705(附属図書館) / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 花崎 秀史, 教授 黒瀬 良一, 教授 稲室 隆二 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

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This dissertation proposes a novel computer modeling (DTFLOP modeling) technique to predict the real-time behavior of dynamic systems. The proposed DTFLOP modeling classifies the computation into the sequential computation, which is conducted on the CPU, and the parallel computation, which is performed on the GPU and formulates the data transmission between the CPU and the GPU using the parameters of the memory access speed and the floating point operations to be carried out on the CPU and the GPU by relating the calculation rate respectively. With the help of the proposed DTFLOP modeling it is possible to estimate the time cost for computing the model that represents a dynamic system given a certain computer. The proposed DTFLOP modeling can be utilized as a general method to analyze the computation of a model related to a dynamic system and two real life systems are selected to demonstrate its performance, the cooperative autonomous vehicle system and the full-field measurement system. For the cooperative autonomous vehicle system a novel parallel grid-based RBE technique is firstly proposed. The formulations are derived by identifying the parallel computation in the prediction and correction processes of the RBE. A belief fusion technique, which fuses not only the observation information but also the target motion information, has hen been proposed. The proposed DTFLOP modeling is validated using the proposed parallel grid-based RBE technique with the GPU implementation by comparing the estimated time cost with the actual time cost of the parallel grid-based RBE. The superiority of the proposed parallel grid-based RBE technique is investigated by a number of numerical examples in comparison with the conventional grid-based RBE technique. The belief fusion technique is examined by a simulated target search and rescue test and it is observed to maintain more information of the target compared with the conventional observation fusion technique and eventually leads to the better performance of the target search and rescue. For the full-field measurement system a novel parallel DCT full-field measurement technique for measuring the displacement and strain field on the deformed surface of a structure is proposed. The proposed parallel DCT full-field measurement technique measures the displacement and strain field by tracking the centroids of the marked dots on the deformed surface. It identifies and develops the parallel computation in the image analysis and the field estimation processes and then is implemented into the GPU to accelerate the conventional full-field measurement techniques. The detail strategy of the GPU implementation is also developed and presented. The corresponding software package, which also includes a graphic user interface, and the hardware system consist of two digital cameras, LED lights and adjustable support legs to accommodate indoor or outdoor experimental environments are proposed. The proposed DTFLOP modeling is applied to the proposed parallel DCT full-field measurement technique to estimate its performance and the well match with the actual performance demonstrates the DTFLOP modeling. A number of both simulated and real experiments, including the tensile, compressive and bending experiments in the laboratory and outdoor environments, are performed to validate and demonstrate the proposed parallel DCT full-field measurement technique. / Ph. D.

Field protocol for in-situ biophysical parameters collection Abstract The main aim of diploma thesis is to design a unified protocol intended for collecting of in-situ biophysical parameters of vegetation based on an up-to-now published literature as well as on my own experimental measuring. The key for measuring of high- quality field data, that are suitable for a subsequent validation of remote sensing products, is an implementation of unified rules as well as all the phases of data collecting, a recommended preparation before the very measuring, the choice of a sampling scheme and a processing of measured data. Based on an accessible literature the current methods of LAI data measuring were evaluated and the basic protocol parameters were defined. For designing of a proper parameterization of this protocol an experimental field measurement was carried out. A determination of a suitable number of partial measurements within ESU is given by a relationship between the number of partial measurements and MSE value. The sampling schemes stated in a literature as well as my own designed sampling schemes are subsequently tested in order to determine a suitable sampling scheme. Based on achieved MSE values the most suitable sampling scheme that was later verified in field measuring was evaluated. Based on a field...

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This paper treats a non-intrusive method of measuring electric fields in plasmas and other sensitive or hostile environments. The method is based on the use of an atomic hydrogen beam prepared in the metastable fine structure quantum state 2s1/2. Interaction with the field that is to be measured causes Stark mixing with the closely lying 2p1/2, whose spontaneous decay rate is much higher than that of 2s1/2. As a result, the total transition rate to the ground state and consequently the intensity of the Lyman-α line (121.6nm) is increased. Observations of emitted radiation from a region in which the interaction takes place are used to draw conclusions about the electric field, effectively providing a way to measure it. In the first section, the theory behind the method is described, using time dependent perturbation theory and taking into account both Lamb shift and hyperfine structure. A description of the set-up that we have used to test the theoretical predictions follows and practical aspects related to the operation of the experiment are briefly addressed. Measurements of the dependence of the Lyman-α intensity on both electric field frequency and amplitude are presented and shown to be in agreement with theory. These measurements have been performed in vacuum and in an argon plasma, both for static and RF fields. Two mechanisms, labeled oscillatory and geometrical saturation, that decrease the emitted intensity for strong fields are identified and described, and both are of importance for the future implementation of the studied diagnostic in a fusion device or other plasma experiment. Studies of the field profiles between a pair of electrically polarized plates have been carried out and algorithms for relating measured data to actual values of electric field strength have been developed. For static fields in vacuum, collected data is compensated for geometrical saturation and the resulting profiles are compared to those calculated with a finite element method. Good correspondence is seen in many cases, and where it is not, the discrepancies are explained. Static profile measurements in a plasma show the formation of a sheath whose thickness has been studied while varying discharge current, pressure and plasma frequency. The qualitative dependence of the sheath thickness on these parameters is in accordance with well established theory. When it comes to RF fields, a possible standing wave pattern is detected in the plasma despite problems with low signal to noise ratio. In order to optimize the working conditions of the set-up, effects of charge accumulation due to ions present in the hydrogen beam have been studied as well as errors due to residual particle fluxes during the off-phase when pulsing the beam. A conceptual design suggestion for implementing the method in the edge plasma of a tokamak or another similar device, based on the collected information, is also given.

­^¤åºK­n Electro-optic probing techniques are advancing rapidly in recent years. These techniques have been proven to be an effective tool in parameter extraction of semiconductor devices such as response time, delay time as well as scattering parameters. Not only the magnitude of the electric field but also the direction of the corresponding E-field direction are measured in several developed electro-optic probing system. By incorporated these techniques, the near-field electric field vectors can be estimated and they are valuable information for the analysis of RF circuit devices, e.g., micro-strip transmission line, patch antenna, etc. When probing the 2-D E-field vectors, one can only measure 1-D E-field direction, then rotate the device under test by 90¢X for another orthogonal tangential E-field direction. However the process not only reduces the probing accuracy but also increases the time interval for achieving measurement and lead to obstacles in use. In the thesis, 2D E-field can be obtained without rotating the DUT by using two kinds of modulation schemes, i.e., compressed/stretched deformation modulation(CSDM) and rotational deformation modulation(RDM). These novel techniques provide a total solution for the above bottleneck and improve the sensitivity for different E-field direction. Besides, a heterodyne method is developed to measure the high frequency near-field 2D E-field distribution. By the heterodyne method, the EO probing system can incorporate the CW laser instead of the pulse laser for reducing the cost and enhancing the merits when applied.

Hydropower has been around for more than a century and is considered a mature technology, but with recent advancements in power electronics and simulation capability new exciting ways to increase efficiency and reliability is possible. At Uppsala University a brushless exciter has been constructed for the experimental test rig, SVANTE. Power electronics are mounted on the shaft for control of the generator's excitation current. In addition a wireless control and measurement system is needed to provide the desired switching patterns to the power electronics and to evaluate performance of the system. In this thesis a shaft mounted embedded system for control and measurement is constructed as well as magnetic field sensors with measurement range up to 700mT. The computational power comes from a National Instruments sbRIO-9606. The system has 14 individual totem pole power electronics driving channels, 48 analog input channels for current signals and it communicates wirelessly through a bluetooth connection. The system is tested and works satisfactory but has not been mounted on the rotating side of the generator due to delays in the manufacturing.