Global ETD Search

1	A Method to Use Vibro-Acoustic Waves to Diagnose Pneumothorax and Hemothorax Nichols, Allen B. 01 January 2005 (has links) Whether caused by trauma, internal diseases, or spontaneously; pneumothorax and hemothorax are potentially life threatening illnesses. They are currently primarily diagnosed with x-rays, CT scans, and ultrasound imaging. While these methods are generally reliable, they are not always available to the injured patient. Life threatening pneumothoraces, such as tension pneumothorax, must be treated quickly. When diagnosed correctly, pneumothorax and hemothorax can be quickly mended through insertion of chest tubes. X-rays, CT scans, and ultrasound imaging require large scale equipment and are not always dependable. There is a more reliable, portable, and faster result producing method to diagnose pneumothorax. Vibro-acoustic waves can be sent through the chest and the resulting wave can be measured. By analyzing attenuation characteristics determined by the geometry of the chest structures, it can be determined if the patient's pleural space is healthy, contains air (pneumothrax), or contains fluid (hemothorax). pneumothorax lungs chest cavity FFT signal analyzer inverse Fourier hemothorax diagnosis Engineering
2	Verification of Receiver Equalization by Integrating Dataflow Simulation and Physical Channels Ritter, David M, Smilkstein, Tina 01 June 2017 (has links) (PDF) This thesis combines Keysight’s SystemVue software with a Vector Signal Analyzer (VSA) and Vector Signal Generator (VSG) to test receiver equalization schemes over physical channels. The testing setup, “Equalization Verification,” is intended to be able to evaluate any equalization scheme over any physical channel, and a decision-directed feed-forward LMS equalizer is used as an example. The decision-directed feed-forward LMS equalizer is shown to decrease the BER from 10-2 to 10-3 (average of all trials) over a CAT7 and CAT6A cable, both simulated and physical, for 1GHz and 2GHz carrier, and 80MHz data rate. A wireless channel, 2.4GHz Dipole Antenna, is also tested to show that the addition of the equalization scheme decreases BER from 10-5 to less than 10-5. Then the simulation and equalization parameters (LMS step size, PRBS, etc.) are changed to further verify the equalization scheme. The simulated channel BER results do not always match the physical channel BER results, but the equalization scheme does decrease BER for both wired and wireless channels. Then transistor-based equalization model is created using both HDL SystemVue components and blocks easily implemented by transistors. The model is then verified using HDL, Spice, and SystemVue simulation. Overall this thesis accomplishes its goal of creating a testing setup, Equalization Verification, to show that adding a given simulated equalization scheme in SystemVue can improve the quality of the link, by decreasing BER by at least an order of magnitude, over a specific physical channel. Equalization Decision-directed SystemVue Vector Signal Analyzer Vector Signal Generator CAT7 Signal Processing Systems and Communications
3	Verification of Third Party Components to The Road Telematics Communicator Mantena, Shanmukha Raju January 2020 (has links) The Road Telematics Communicator (RTC) as it is called in Scania. It is the device responsible to keep the vehicle connected and send the vehicle data to the off-board system. It uses data from different sources such as GNSS signals, CAN signal, and wireless Telecom signals. Connected vehicles provide real-time information on positioning, fuel consumption, and vehicle diagnostics. There are acceptance and regression test suites that verify the functionality of RTC. Third-party components such as the GNSS module are not a part of the tests due to technical limitations. Hence RTC lacks automated tests for important features. Due to the lack of complete verification in automated test suites, time-consuming tests must be performed on the road. And trouble reports from the field are difficult to analyze. This thesis provides testing the location accuracy of the GNSS module in vehicles used for telematics applications in the automotive industry, by using a GPS vector signal generator in a controlled lab environment. GNSS consists of GPS, GALILEO, GLONASS, BEIDOU. We are using GPS in this research. The GPS receiver is put under test in a controlled lab environment for testing the Time to First Fix, Location accuracy of GPS receiver, and analyzing the performance with the given inputs. Test cases were created similar to field tests on the signal generator. At this stage, an experiment is performed on the GPS receiver which is connected to the signal generator via RF connector and to a computer via LAN. An input data is sent to the signal generator in the form of SCPI commands. The signal generator processes these commands and generates a signal accordingly. This generated signal is fed to the receiver. With the help of a signal generator, we can generate fields like inputs and verify the behavior of the GPS module. By verifying the behavior of the module, we can develop test cases that show the functionality of the receiver. Telematics Global positioning system Vector signal generator Signal analyzer RF Communication Signal processing Quality assurance Engineering and Technology Teknik och teknologier
4	Frequency Comb Experiments and Radio Frequency Instrumentation Analysis for Optical Atomic Clocks Ryan J Schneider (14187461) 29 November 2022 (has links) <p>Space-based global navigation and precision timing systems are critical for modern infrastructure. Atomic clock technology has increased the precision of these systems so that they are viable for military operations, navigation, telecommunications, and finance. Advances in optical atomic clocks, based on optical frequencies, provide an opportunity for even more precise timing. Therefore, developments in chip-scale optical atomic clock technologies could lead to increased and more wide-spread application of this precision timing. One component of the optical atomic clock is the optical frequency comb which serves as an interface between optical and microwave frequencies. This thesis will cover experiments related to these optical frequency combs. A 2$\mu$m fiber laser was developed in order to test second harmonic devices required to stabilize an optical frequency comb. The laser was then employed to measure the operating wavelengths and efficiencies of non-linear devices. In addition, an analysis of the radio frequency instruments used to evaluate microwave outputs was conducted to determine whether a digital signal analyzer (oscilloscope) or an analog electronic spectrum analyzer provides more accurate results for optical frequency comb based experiments.</p> Optical Atomic Clock Optical Frequency Comb Tunable Fiber Laser Second Harmonic Generation Digital Signal Analyzer Electronic Spectrum Analyzer
5	Improved frequency domain measurement techniques for characterizing power amplifier and multipath environments McKinley, Michael Dean 19 August 2008 (has links) This work focuses on fixing measurement inaccuracies to which models and figures of merit are susceptible in two wireless communication environments: power amplifier and multipath. To emulate or rate the performance of these environments, models and figures of merit, respectively, are often used. The usefulness of a model depends on how accurately and efficiently it emulates its real-world counterpart. The usefulness of a figure of merit depends on how accurately it represents system behavior. Most discussions on the challenges and trade-offs faced in modeling nearly always focus on the complexity of the device or channel of interest and the resultant difficulty in describing it. Similarly, figures of merit are meant only to summarize the performance of the device or channel. At some point, either in generation or verification of a model or figure of merit, there is a dependence on measured data. Though the complexity and performance of the device or channel are challenges by themselves, there are other significant sources of distortion that must be minimized to avoid errors in the measured data. For this work, the unique distortion of power amplifier and multipath environments is considered, and then errors in measurement which would obscure these distortions are eliminated. Specifically, three measurement issues are addressed: 1) identifying measurement setup artifacts, 2) achieving consistent measurement results and 3) reducing variations in the environment. This work contributes to increasing the accuracy of microwave measurements used in the modeling of nonlinear high-power amplifiers and used in figures of merit for power amplifiers and multipath channels. CDMA Code division multiple access Multisine error vector magnitude Multisine OFDM Wiener Parallel Wiener Memory Class AB Two tone measurement Asymmetry IMD Intermodulation distortion Spectral leakage VSA Vector signal analyzer Rayleigh Rice Gauss Power amplifier Multipath Measurement Microwave Error vector magnitude Wireless communication systems Microwave measurements Amplifiers (Electronics) Simulation methods

1

Page generated in 0.0634 seconds