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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Software pro komunikaci s GPS přijímačem / Software for Communication with GPS Receiver

Vrba, Pavol January 2011 (has links)
The main goal of this master’s thesis is to over study, reconsider and make a program, which will be capable to interpose information from GPS module, different markers and necessary information’s, geographic coordinates obtained from GPS will be projected in its interface and also on map. This project contains of 3 parts. The first one exactly describes GPS, its history, structure, principle, competitive types of navigations systems and also GPS’ services and technical parameters. The second part of this project describes GPS hardware, used receiver of this signal. There is also mentioned its technical parameters and communication with outside world. The third part is in scripted the software for communication with GPS receiver. We can also see the description of code, in which is mentioned communication protocol and imaging the position on the map. It was programmed in C# language on platform Microsoft Visual Studio 2008 Express Edition.
142

Evidence of Dynamic Crustal Deformation in Tohoku, Japan, From Time-Varying Receiver Functions

Porritt, R. W., Yoshioka, S. 10 1900 (has links)
Temporal variation of crustal structure is key to our understanding of Earth processes on human timescales. Often, we expect that the most significant structural variations are caused by strong ground shaking associated with large earthquakes, and recent studies seem to confirm this. Here we test the possibility of using P receiver functions (PRF) to isolate structural variations over time. Synthetic receiver function tests indicate that structural variation could produce PRF changes on the same order of magnitude as random noise or contamination by local earthquakes. Nonetheless, we find significant variability in observed receiver functions over time at several stations located in northeastern Honshu. Immediately following the Tohoku-oki earthquake, we observe high PRF variation clustering spatially, especially in two regions near the beginning and end of the rupture plane. Due to the depth sensitivity of PRF and the timescales over which this variability is observed, we infer this effect is primarily due to fluid migration in volcanic regions and shear stress/strength reorganization. While the noise levels in PRF are high for this type of analysis, by sampling small data sets, the computational cost is lower than other methods, such as ambient noise, thereby making PRF a useful tool for estimating temporal variations in crustal structure.
143

Low Power Receiver Architecture And Algorithms For Low Data Rate Wireless Personal Area Networks

Dwivedi, Satyam 12 1900 (has links) (PDF)
Sensor nodes in a sensor network is power constrained. Transceiver electronics of a node in sensor network consume a good share of total power consumed in the node. The thesis proposes receiver architecture and algorithms which reduces power consumption of the receiver. The work in the thesis ranges from designing low power architecture of the receiver to experimentally verifying the functioning of the receiver. Concepts proposed in the thesis are: Low power adaptive architecture :-A baseband digital receiver design is proposed which changes its sampling frequency and bit-width based on interference detection and SNR estimation. The approach is based on Look-up-table (LUT) in the digital section of the receiver. Interference detector and SNR estimator has been proposed which suits this approach. Settings of different sections of digital receiver changes as sampling frequency and bit-width varies. But, this change in settings ensures that the desired BER is achieved. Overall, the receiver reduces amount of processing when conditions are benign and does more processing when conditions are not favorable. It is shown that the power consumption by the digital baseband can be reduced by 85% (7 times) when there is no interference and SNR is high. Thus the proposed design meets our requirement of low power hardware. The design is coded in Verilog HDL and power and area estimation is done using Synopsys tools. Faster Simulation Methodologies :-Usually physical layer simulations are done on baseband equivalent model of the signal in the receiver chain. Simulating Physical layer algorithms on bandpass signals for BER evaluation is very time consuming. We need to do the bandpass simulations to capture the effect of quantization on bandpass signal in the receiver. We have developed a variance measuring simulation methodology for faster simulation which reduces simulation time by a factor of 10. Low power, Low area, Non-coherent, Non-data-aided joint tracking and acquisition algorithm :-Correlation is a very popular function used particularly in synchronization algorithms in the receivers. But correlation requires usage of multipliers. Multipliers are area and power consuming blocks. A very low power and low area joint tracking and acquisition algorithm is developed. The algorithm does not use any multiplier to synchronize. Even it avoids squaring and adding the signals to achieve non-coherency. Beside the algorithm is non-data-aided as well and does not require ROM to store the sequence. The Algorithm saves area/power of existing similar algorithms by 90%. Experimental setup for performance evaluation of the receiver :-The developed baseband architecture and algorithms are experimentally verified on a wireless test setup. Wireless test setup consists of FPGA board, VSGs, Oscilloscopes, Spectrum analyzer and a discrete component RF board. Packet error and packet loss measurement is done by varying channel conditions. Many practical and interesting issues dealing with wireless test setup infrastructure were encountered and resolved.
144

DETECTION AND EXCLUSION OF FAULTY GNSS MEASUREMENTS: A PARAMETERIZED QUADRATIC PROGRAMMING APPROACH AND ITS INTEGRITY

Teng-yao Yang (8742285) 23 April 2020 (has links)
<div>This research investigates the detection and exclusion of faulty global navigation satellite system (GNSS) measurements using a parameterized quadratic programming formulation (PQP) approach. Furthermore, the PQP approach is integrated with the integrity risk and continuity risk bounds of the Chi-squared advanced receiver autonomous integrity monitoring (ARAIM). The integration allows for performance evaluation of the PQP approach in terms of accuracy, integrity, continuity, and availability, which is necessary for the PQP approach to be applied to the vertical navigation in the performance-based navigation (PBN). In the case of detection, the PQP approach can also be integrated with the vertical protection level and the associated lower and upper bounds derived for the solution separation ARAIM. While there are other computationally efficient and less computationally efficient fault detection and</div><div>exclusion methods to detect and exclude faulty GNSS measurements, the strength of the PQP approach can summarized from two different perspectives. Firstly, the PQP</div><div>approach belongs to the group of the computationally efficient methods, which makes the PQP approach more favorable when it comes to detect and exclude multiple simultaneous faulty GNSS measurements. Secondly, because of the integration of the PQP approach with the integrity risk and continuity risk bounds of the Chi-squared</div><div>ARAIM, the PQP approach is among the first computationally efficient fault detection and exclusion methods to incorporate the concept of integrity, which lies in</div><div>the foundation of PBN. Despite the PQP approach not being a practical integrity monitoring method in its current form because of the combinatorial natural of the integrity risk bound calculation and the rather conservative integrity performance, further research can be pursued to improve the PQP approach. Any improvement on the integrity risk bound calculation for the Chi-squared ARAIM can readily be</div><div>applied to the integrity risk bound calculation for the PQP approach. Also, the connection between the PQP approach and the support vector machines, the application of the extreme value theory to obtain a conservative tail probability may shed light upon the parameter tuning of the PQP approach, which in turn will result in tight integrity risk bound.</div>
145

Výukový GPS přijímač / Educational GPS Receiver

Cséfalvay, Gabriel January 2010 (has links)
This work explicates a simple GPS receiver intended for laboratory demonsration of DSSS signal demodulation and apparent distance measurement. The receiver will be able to seek for individual sattelite signals, measure their shift against local oscillator, demodulate navigational data, display information on LCD and communicate with PC via USB.
146

Software pro komunikaci s GPS přijímačem / Software for Communication with GPS Receiver

Vrba, Pavol January 2011 (has links)
The main goal of this master’s thesis is to over study, reconsider and make a program, which will be capable to interpose information from GPS module, different markers and necessary information’s, geographic coordinates obtained from GPS will be projected in its interface and also on map. This project contains of 3 parts. The first one exactly describes GPS, its history, structure, principle, competitive types of navigations systems and also GPS’ services and technical parameters. The second part of this project describes GPS hardware, used receiver of this signal. There is also mentioned its technical parameters and communication with outside world. The third part is in scripted the software for communication with GPS receiver. We can also see the description of code, in which is mentioned communication protocol and imaging the position on the map. It was programmed in C# language on platform Microsoft Visual Studio 2008 Express Edition.
147

Uživatelské aplikace pro satelitní přijímače / User Applications for Satellite Receivers

Dorušák, Petr January 2015 (has links)
This thesis presents principles of transmission of digital television broadcasting via satellite placed in orbit of Earth. It also focuses on the satellite receiver as an important part of satellite systems. It mention receiver&#8217;s firmware and deals with design and implementation of satellite receiver&#8217;s application.  The aim is to create an application that will personalize satellite receiver by monitoring TV stations that have been watched.
148

Design and Implementation of a 5.8 GHz superheterodyne FM Video Receiver

Stålberg, Carl-Johan January 2019 (has links)
This master thesis presents the design and implementation of a super heterodyne 5.8 GHz receiver system for wireless transmission of phase alternating line (PAL) composite video signals. The system is implemented using surface and hole mounted devices on four separate printed circuit board (PCB) stages. These stages include a 5.8 GHz radio front-end, a 480 MHz intermediate frequency (IF) stage, a local oscillator (LO) block and frequency demodulation circuit for frequency modulation (FM) signals. Each receiver stage is interconnected using sub-miniature version A (SMA) connectors. The radio front-end PCB consists of a low-noise amplifier (LNA), a 5.8 GHz distributed element pre-select filter and a passive double-balanced mixer. This mixer uses seven discrete injection frequencies at 5260-5380 MHz that are provided by the LO block using a programmable phase-locked loop (PLL) frequency synthesizer device. The IF stage uses an automatic gain control (AGC) feedback loop with a dynamic range of 60 dB. This AGC loop is implemented using a directional coupler, a detector device, a tuning circuit and a variable gain amplifier/attenuator (VGA). The IF at 480 MHz is selected with a 25 MHz surface acoustic wave (SAW) filter. The IF is demodulated to a PAL composite video format using a PLL FM discriminator device intended for direct-broadcast satellite (DBS) signals. This device is fitted to a separate demodulation stage in conjunction with a picture adjustment circuit and a FM de-emphasis network. The output of the demodulator stage is a 75 Ω PAL composite video signal.
149

Optimization of Cavity Receiver Geometry with regards to Radiation Heat Loss

Ottosson, Simon, Wahlgren, Fredrik January 2016 (has links)
In order to maximize the e ciency of power generation in concentrated solar power systems (CSP) it is de- sired to achieve as high a tempera- ture in the receiver as possible due to the use of the Sterling cycle to gen- erate power. This report investigates three di↵erent geometries for cavity receivers in CSP systems; cylindrical, conical and truncated conical. The goal has been to minimize the heat loss due to radiation. This was achieved through mathematical mod- eling with the help of MATLAB. Five di↵erent cases with regards to oper- ating temperature and proportions of the receiver where investigated for each of the three chosen geometries. It was found that the conical geometry minimized this heat loss in all except one case.
150

A New Era for Wireless Communications Physical Layer: A Data-Driven Learning-Based Approach.

Al-Baidhani, Amer 23 August 2022 (has links)
No description available.

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