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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.
61

A Novel Variable Inductor-Based VCO Design with 17% Frequency Tuning Range for IEEE 802.11AD Applications

Meng, YIN FEI 23 January 2014 (has links)
This thesis focuses on the design and analysis of a novel variable inductor (VID) based VCO solution to the frequency tuning range (TR) limitation of the IEEE 802.11ad compliant radio systems. The IEEE 802.11ad standard has drawn strong attention from the industry as the next generation affordable multi-gigabit speed wireless communication standard. Prepared for the global market, IEEE 802.11ad compliant systems are required to cover a broad 8 GHz TR centered on 60 GHz. This wide TR at V band imposes significant challenge to the VCO design in radio transceivers, and makes the TR of the integrated VCO a major bottleneck to the successful commercialization of many IEEE 802.11ad compliant radio systems today. As an effort to solve the current TR problem for the IEEE 802.11ad compliant radio systems, 2 VCOs designs based on this novel VID-based solution and a conventional Colpitts-Clapp VCO design are presented in this thesis report. The novel VCOs integrate a VID into the differential Colpitts configuration to create a feasible solution to the aforementioned TR problem. The VID in the VCO tank eliminates the base node varactors and their fixed parasitic capacitance that degrades TR in conventional VCO designs, while the differential Colpitts configuration provides advantageous performance at mm-wave frequencies and high output power for real-world applications. Also, a fundamental 30 GHz Colpitts-Clapp VCO was developed in conjunction with the other 2 VCOs for comparison purposes. One of the 2 VID-based VCO designs is a fundamental 30 GHz VID-based Colpitts VCO that covers 17% TR for proof of concept to the novel topology. Another is an IEEE 802.11ad compliant 60 GHz VCO chain consists of the 30 GHz VID-based Colpitts VCO and a frequency doubler covering 17% TR with 3 dBm output power and -115.7 dBc/Hz phase noise at 10 MHz offset. The conventional Colpitts-Clapp VCO is used to compare with the other 2 VID-based VCOs. As the measurement results indicate, this VID-based VCO topology provides a viable solution to overcome the TR bottleneck in the current IEEE 802.11ad compliant VCO development. All 3 VCOs are fabricated using a 130 nm SiGe BiCMOS process. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2014-01-23 13:40:31.258
62

Searches for a Charged Higgs Boson in ATLAS and Development of Novel Technology for Future Particle Detector Systems

Pelikan, Daniel January 2015 (has links)
The discovery of a charged Higgs boson (H±) would be a clear indication for physics beyond the Standard Model. This thesis describes searches for charged Higgs bosons with the ATLAS experiment at CERN’s Large Hadron Collider (LHC). The first data collected during the LHC Run 1 is analysed, searching for a light charged Higgs boson (mH±<mtop), which decays predominantly into a tau-lepton and a neutrino. Different final states with one or two leptons (electrons or muons), as well as leptonically or hadronically decaying taus, are studied, and exclusion limits are set. The background arising from misidentified non-prompt electrons and muons was estimated from data. This so-called "Matrix Method'' exploits the difference in the lepton identification between real, prompt, and misidentified or non-prompt electrons and muons. The Matrix Method is used in all charged Higgs boson searches in this thesis. In 2024 the LHC will be upgraded into a High Luminosity LHC (HL-LHC). The ATLAS detector is expected to collect around 300 fb-1 of collision data until 2022, whereas the HL-LHC will deliver about 250-300 fb-1 of data per year. This will increase the mean number of interactions per bunch crossing, resulting in larger particle fluxes. This puts challenging requirements on the electronics. In order to keep trigger and data rates at manageable levels, new trigger concepts require more intelligence at early stage which possibly results in more cables and connectors, inside the detector which lead to degraded performance of the detector system. This thesis presents new concepts using wireless technology at 60 GHz, in order add more data links inside the detector system without adding much material. Patch antennas have been developed, operating at 60 GHz. Manufacture methods have been investigated, and the fabrication tolerances and bandwidth of these antennas have been studied. Also, concepts of using passive repeaters have been investigated, to make the 60 GHz signal pass boundaries. These repeaters can be used to connect intelligence inside the detector, but also for reading out data from the whole detector radially.
63

Ultra-low power programmable processor architecture for 60 GHz digital front-end / Προγραμματιζόμενη αρχιτεκτονική επεξεργαστών πολύ χαμηλής κατανάλωσης για ψηϕιακό front-end στα 60 GHz

Μπεμπέλης, Ευάγγελος 19 July 2012 (has links)
Modern embedded systems complexity, performance and energy efficiency has been increasing steeply the last few years. An explosive growth in demand for wireless communication is observed as well and modern wireless links are expected to deliver bit rates of several gigabits while consuming even less energy. In order to satisfy these needs new technologies emerge and novel design approaches are put into practice. Communication at 60 GHz is such a technology that is able to deliver high bit rates in short range wireless links. A major motivation to use the 60 GHz spectrum is the worldwide availability which makes exploitation economically viable. Moreover, small wavelength of only 5 mm promises high integration due to small antenna component size which is one of the main bottlenecks for reducing the dimensions. However, increased frequency comes with many disadvantages as well. To increase the market potential of such a new technology the chip design needs to be cheap and energy-efficient. Such cost and energy constrains heavily impact the performance and the quality of both the analog and the digital components of the chip. In the current thesis the design possibilities of a component in the digital baseband of the receiver of such a chip are explored. The component under investigation is a Fast Fourier Transform (FFT) that is used for frequency domain equalization. This part of the receiver is used to reduce the effects of multipath in a non line-ofsight communication environment and as this is a common case in wireless communication the FFT block has been identified as one of the 2 most computational intensive components of the receiver in 60 GHz. This is the main reason why we explore possibilities to further decrease the power consumption of the block while maintaining the performance and the quality of service. To achieve this reduction the possibilities of a new design concept are explored. System Scenarios is a new design concept for embedded systems operating in dynamic environments. Wireless communication systems exhibit high dynamism during their operation on highly varying data streams, providing the System Scenarios huge xvi capabilities. The essential idea behind system scenarios is the classification of the application under investigation from a cost perspective during design time. Then, the classification is exploited during run time resulting to an overall improved implementation of the application. To achieve this the application is broken down to run-time situations (RTS) which are distinguishable operation modes of the application. Then RTSs with similar costs are clustered to form system scenarios. Finally for each scenario a different mapping and scheduling of the application is generated. In the case of the current thesis the application is the FFT and the cost perspective is the power consumption of the component. To exploit the RTS clustering in run time different quantization schemes have been produced. These schemes have been generated based on various properties of the data waveforms in the input of the FFT. The thesis explores the potential of the System Scenarios as well as the application of a quantization methodology for the FFT. Different options of the RTS clustering and the quantization of the FFT block are evaluated in order to come up with a more efficient implementation. / Τα σύγχρονα ηλεκτρονικά συστήματα παρέχουν στους χρήστες έναν καθημερινά αυξανόμενο αριθμό υπηρεσιών και λειτουργιών. Η ζήτηση τς αγοράς για ϕθηνές, αξιόπιστες και ϕορητές ηλεκτρονικές συ- σκευές ωθεί τα όρια του σχεδιασμού των ενσωματωμένων συστημάτων σε νέες ανεξερεύνητες περιοχές. Η ϕορητότητα απαιτεί την αϕαίρεση όλων των καλωδίων είτε για μετάδοση δεδομένων είτε για ενέργεια. Για να επιτευχθεί αυτό, η ασύρματη επικοινωνία σε υψηλό ρυθμό μετάδοσης είναι επιθυμητή χωρίς να θυσιαστεί η υψηλή ενεργειακή απο- δοτικότητα που καθιστά την συσκευή αυτόνομη από το ενεργειακό δίκτυο για μεγάλες χρονικές περιόδους. Η συνεχής αύξηση στις προδιαγραϕές των σύγχρονων ενσωματομένων συστημάτων έχει οδηγήσει στην χρήση καινοτόμων ιδεών, προσεγγίσεων και τεχνολογιών. Μια νέα τεχνολογία που υπόσχεται υψηλή ολοκλήρωση και υψηλό ρυθμό μετάδοσης δεδομένων στις ασύρματες ζεύξεις είναι η επικοινωνία στα 60 GHz. Μια νέα προσέγγιση σχεδιασμού για ενσωματομένα συστήματα υπόσχεται αποτελεσματική εκμετάλευση του δυναμισμού που μπορεί να παρουσιάζει ένα σύστημα. Τα ασύρματα συστήματα επικοινωνίας λειτουργούν τυπικά σε πολύ δυναμικά περιβάλλοντα. Τα Σενάρια συστήματος έχουν μεγάλες δυνατότητες για να βελτιώσουν την αποτελεσματικότητα της υλοποίησης των ψηϕιακών βάσεων τέτοιων συστημάτων. Στην παρούσα διπλωματική εξερευνούμε της δυνατότητες της αρχιτεκτονικής του FFT που βρίσκεται στην πλευρά του δέκτη ενός πομποδέκτη στα 60 GHz. Ο FFT είναι μέρος της εξίσωσης στο πεδίο της συχνότητας που χρησιμοποιείται για να μειώσει της επιδράσεις του ϕαινομένου multipath. Χρησιμοποιώντας Σενάρια Συστήματος προσπαθούμε να καταλήξουμε με μια πιο προσαρμοστική και συνεπώς πιο ενεργειακά αποδοτική υλοποίηση του μετασχηματισμού. Η εϕαρμογή των Σεναρίων Συστήματος χρησιμοποιώντας δεδομένα ως παράμετρο είναι μια καινοτόμα προσέγγιση και σε αυτή την διπλωματική εργασία ελέγχουμε την επιτευξιμότητα της. Για να επιτύχουμε κάτι τέτοιο πρέπει να μπορούμε να παράγουμε πολλαπλά διαϕορετικά σχέδια κβαντοποίησης του μετασχηματισμού σε αποδεκτά χρονικά διαστήματα. Οι παρούσες μέθοδοι κβαντοποίησης δεν μπορούν ακόμα να παρέχουν τέτοια δυνατότητα. Έτσι βασιζόμενοι στην επέκταση μια υπάρχουσας μεθοδολογίας προτείνουμε μια ολοκληρωμένη μεθοδολογία που μπορεί να παράγει σχέδια κβαντοποίησης μεγάλων στοιχείων υλικού όπως ο FFT.
64

High level estimations on the 60 GHz digital baseband

Σαμαράς, Κωνσταντίνος 06 December 2013 (has links)
Στο πεδίο των ασύρματων επικοινωνιών της τάξης των 60 GHz που αντιστοιχούν σε ρυθμούς μετάδοσης multi-gigabits ανά δευτερόλεπτο, οι σύγχρονες υλοποιήσεις βασίζονται στα ιδιαίτερα προσαρμοζόμενα ASICs, ανάλογα με τις ανάγκες της εφαρμογής. Απαιτούνται γενικώς υψηλές ταχύτητες επεξεργασίας σε συνδυασμό με χαμηλή κατανάλωση ενέργειας. Ωστόσο, για να υποστηριχθούν διαφορετικά πρότυπα με μεγάλη διαφοροποίηση τρόπων χρήσης, είναι ιδιαίτερα επιθυμητές λύσεις αρχιτεκτονικής που μπορούν να προγραμματιστούν και να ρυθμιστούν έτσι ώστε αυξάνοντας το δυνατό αγοραστικό κοινό, να μειωθεί το κόστος επεξεργασίας ανά chip. Στις μέρες μας, τα ASIPs (Application-Specific Instruction-set Processors) δεν είναι εφικτά λόγων των υψηλότατων απαιτήσεων απόδοσης/ενέργειας. Ωστόσο, το κενό που υπάρχει με τα ASICs μπορεί κατά μεγάλο μέρος να γεφυρωθεί ή και να εξαλειφθεί, εισάγοντας και χρησιμοποιώντας ποιο δυναμική συμπεριφορά στην ψηφιακή front-end λειτουργικότητα. Για να επιτευχθεί αυτό, απαιτούνται καινοτομίες στην πλευρά της αρχιτεκτονικής του επεξεργαστή και ειδικότερα στον τρόπο που οι αλγόριθμοι αντιστοιχίζονται σε αυτές τις απαιτήσεις. Ξεκινώντας από παλαιότερα πειράματα που έδειξαν ότι η ιδέα αυτή είναι εφικτή, τα αντιπροσωπευτικά αλγοριθμικά τμήματα (με βάση κυρίως τον FFT) θα αντιστοιχηθούν στην επιλεγμένη αρχιτεκτονική ASIP για εφαρμογές στα 60 GHz. Σε αυτά τα πλαίσια, θα εφαρμοστεί η μεθοδολογία του διαγράμματος ροής εκτιμήσεων υψηλής κλίμακας (high level estimations flowchart). Πιο συγκεκριμένα, αρχικά θα αποκτηθεί μια πιο ακριβής καταγραφή του λειτουργικού κόστους της αλυσίδας φορτίου δεδομένων του ψηφιακού μέρους του δέκτη που υλοποιεί το πρότυπο επικοινωνιών στα 60 GHz. Στη συνέχεια θα κβαντιστούν οι πιο πολύπλοκοι, λειτουργικά, πυρήνες της αλυσίδας, όπως θα προκύψει από το προηγούμενο βήμα και τελικά οι πυρήνες αυτοί θα αντιστοιχηθούν σε αναδιαμορφώσιμα αρχιτεκτονικά μοντέλα. Η εργασία θα επικεντρωθεί στον FFT, που αναμένεται να έχει τη μέγιστη λειτουργική πολυπλοκότητα και θα προταθεί μια διαφορετική προσέγγιση για τον τρόπο προσπέλασης των δεδομένων και των συντελεστών στην SRAM και το register file, με στόχο την ελάττωση της κατανάλωσης ενέργειας του πυρήνα αυτού. Τέλος, θα παρατεθεί μια συγκριτική μελέτη των σχημάτων πρόσβασης που θα ερευνηθούν. Με αυτόν τον τρόπο μπορούν να ποσοτικοποιηθούν τα συνολικά κέρδη της έρευνάς μας. / In the domain of multi-gigabits per second wireless 60 GHz communication transceivers and beyond, today's implementations are all based on heavily customized application-specific integrated circuits (ASICs). The basic motivation for this customization is the extremely high processing speeds that are required, in combination with the need for low energy consumption. However, to support different standards and highly varying usage modes, more programmable or configurable architecture solutions are strongly desirable to increase the potential market volume and in this way to reduce the per-chip processing costs. Today these application-specific instruction set processors or ASIPs are not feasible due to the too high performance/energy requirements. Nevertheless, we believe that by introducing and exploiting more dynamic behavior in the digital front-end functionality, the performance/energy gap with the ASICs can be largely bridged and potentially even fully overcome. In order to achieve this, innovations are required on the processor architecture side and especially on the way algorithms are mapped to those architectures. In this thesis, we will start from earlier experiments which have shown the viability of the above concept. Τhe representative algorithmic blocks (mainly FFT oriented) will be mapped onto reconfigurable hardware based on ASIP architectures for 60 GHz applications. In this way we can quantify the overall gains and check how far the approach can be extended to exploit all the available dynamism using the concept of scenario clustering. In this context, we will follow the steps of the high level estimations flowchart methodology. In particular, we will obtain a more accurate account of the operational complexity of the digital base-band payload chain kernels, quantize the most complex of them and then map them in reconfigurable architectures. Especially for the FFT kernel, that is expected to show the highest complexity, we will implement a different approach in the accessing of the data and coefficients that intends to limit the energy usage of the kernel. For this purpose, we will end this work with a comparative study of different schemes explored.
65

Self Resonant Third Harmonic Mixer For 60 GHz Transmitter

January 2010 (has links)
abstract: ABSTRACT Ongoing research into wireless transceivers in the 60 GHz band is required to address the demand for high data rate communications systems at a frequency where signal propagation is challenging even over short ranges. This thesis proposes a mixer architecture in Complementary Metal Oxide Semiconductor (CMOS) technology that uses a voltage controlled oscillator (VCO) operating at a fractional multiple of the desired output signal. The proposed topology is different from conventional subharmonic mixing in that the oscillator phase generation circuitry usually required for such a circuit is unnecessary. Analysis and simulations are performed on the proposed mixer circuit in an IBM 90 nm RF process on a 1.2 V supply. A typical RF transmitter system is considered in determining the block requirements needed for the mixer to meet the IEEE 802.11ad 60 GHz Draft Physical Layer Specification. The proposed circuit has a conversion loss of 21 dB at 60 GHz with a 5 dBm LO power at 20 GHz. Input-referred third-order intercept point (IIP3) is 2.93 dBm. The gain and linearity of the proposed mixer are sufficient for Orthogonal Frequency Division Multiplexing (OFDM) modulation at 60 GHz with a transmitted data rate of over 4 Gbps. / Dissertation/Thesis / M.S. Electrical Engineering 2010
66

Optimización de la razón señal a ruido de un receptor a 115 ghz para fines radioastronómicos.

Vásquez Drouilly, Cristián Claudio January 2007 (has links)
No description available.
67

Design and Test of: Wide Band and Highly Polarized Antenna for 60GHz

Larsson, David January 2017 (has links)
In this work  high gain antennas are investigated for the 60 GHz frequency. The goal is to produce a high bandwidth point-to-point wireless network that could enable improved and new features in embedded systems used to detect particles in high energy physics. A literature study was performed aiming at simple, high gain, highly polarised antennas. Complex designs were grouped into three different groups: flat antenna design, build-up design and multi-antenna design. The multi-antenna design was found to have the simplest design and manufacturing but also feature larger antenna area. Three different designs were produced and tested, standard patch antenna, long patch antenna and a Vivaldi antenna. Manufacturing of a 4-patch antenna was also tested. All three demonstrated expected properties, the Vivaldi shows the best gain while the long patch antenna is slightly below the standard patch antenna. A forth design implementation was also tested using a 3D-printed lens. A lens can increase gain and allow changing beam direction. A lens was design and tested, the results showed an increased gain but with varying results at angels. Antennas were designed and manufactured using simple etching technique showing that further research can be done using simple and easily accessible techniques. Both antenna and lens show good properties and should be further investigated and validated. / I det här arbetet har antenner med hög förstärkning vid frekvensen 60 GHz undersökts. Målet är att utveckla punkt-till-punkt nätverk med hög bandbredd för detektorer i partikelkolliderare. Idag används trådade nätvärk i detektorn, genom att byta till trådlös dataöverföring kan onödig massa minskas och kvalitet förbättras. En litteraturstudie genomfördes med inriktning mot enkla, starkt förstärkande och kraftigt polariserad antenner. Tre olika typer defineras: platta designer, uppbygda designer och antenngrupper. Antenngrupper var de med enklaste design och tillverkning men också de med störst area relativt de andra. Tre olika antenner tillverkades och testades: patchantenn, lång patchantenn och Vivaldiantenn. Även en 4-patch antenn tillverkades. Produktionen av alla antenner höll hög kvalitet och de testade egenskaperna var förväntade. Vivaldiantennen hade starkast förstärkning av de testade antennerna, den långa patchantennen presterade strax under standard patchantennen. Även tester av en antenngrupp bestående av en patch antenn oc hen antennlins gjordes. Genom att använda en lins kan förstärkningen ökas och riktningen ändras. En lins designades och tillverkades med en 3D-skrivare. Resultat från tester visade på en ökad förstärkning men med varierande resultat vid vinklar. Antenner designades och tillverkades med en enkel etsningsmetod, detta visar att forsatta undersökningar kan utnyttja enkel och lättilgänlig teknik. Goda resultat uppvisades med både antenner och lins. Framtida studier kan utföras för att vidarutveckla och validera konceptet.
68

NMR studies of the structure of a conserved RNA motif of 23S ribosomal RNA and its interaction with peptidyl transferase antibiotics

King, John January 2011 (has links)
In this project a number of peptidyl transferase antibiotics were studied, specifically a group of aminohexose cytosine nucleoside antibiotics and their interaction with a selected number of highly conserved ribonucleic acid (RNA) motifs, designed to represent their possible binding site within the ribosome. This group of antibiotics shows a wide range of interesting properties, including antiviral and anti-tumour activity, and as they bind to a particularly conserved region in the ribosome, they are likely to be difficult for microorganisms to develop resistance to. It is hoped that once the mechanism of action of these antibiotics is better understood, that modifications to the antibiotics can be effectively made to create new or hybrid antibiotics with more selective antibacterial, or indeed antiviral or anti-tumour properties. The nuclear magnetic resonance (NMR) structure of the RNA binding, peptidyl tranferase inhibitor antibiotics amicetin, blasticidin S and gougerotin, in their native solution states, have been successfully determined. The structures all exhibit a stable conformation, stabilised by intramolecular hydrogen bonds. Amicetin was observed to be folded, distinctly different from the linear, extended conformation of amicetin previously determined by X-ray crystallography. The structure of blasticidin S was found to be very similar to its X-ray crystal structure. Gougerotin was shown to form a similar conformation to blasticidin S, save that the end chain of gougerotin was bent at right angles to the rest of the molecule, forming a structure similar to that of the major bound X-ray crystal structure of blasticidin S. All the solution structures showed a similar conformation in the analogous regions of their chemical structure, suggesting that hybrid antibiotics could be produced.Two highly conserved RNA motifs of Halobacterium halobium (H. h.) and Escherichia coli (E. coli) 23S ribosomal RNAs were chosen to investigate their interaction with amicetin. The NMR structure of the H. h. and E. coli. 29-mer RNA motifs have been determined; the motifs both form well folded A-form RNA conformations. The E. coli NMR structure differs from the X-ray crystal structure of the motif contained within the ribosome, as a highly conserved adenine residue, which resides in a bulge strongly implicated with amicetin binding, folds into the helix as opposed to being flipped out. Instead, an adjacent cytosine residue partially flips out; whereas in the crystal structure, it is folded within the helix. The NMR stuctures of the H. h. motif differs from the X-ray crystal structure of the motif, contained within the ribosome, as none of the bases are flipped out and a number of non-canonical base pairs are formed in the solution structure. To continue this study, a fully 13C and 15N isotopically labelled version of the H. h. RNA sample has been partially assigned, and an initial structure determination has been performed, using ultra high field 1 GHz spectroscopy.Addition of amicetin to both the H. h. and E. coli 29-mer RNA samples were accompanied by discrete changes to the spectra, suggesting weak interaction between the two components. These can be qualitatively interpreted to changes induced in the local conformation of the RNA motifs and the amicetin arising from the formation of a complex, between the amicetin and the bulge region of the particular motif.
69

Application of microwave sensors to potato products

Mohamad Noh, Badaruzzaman Bin January 2010 (has links)
The first microwave measurement techniques uses an open ended coaxial probe with a purposely built sample holder to measure the dielectric properties of potato products from 500 MHz to 1 GHz. The second system utilises a waveguide cell with a purposely built sample holder to characterise potato products from 2.4 to 3.5 GHz. Common British varieties of raw potatoes such as Estima, King Edward and Maris Piper are used in this study. The two microwave measurement techniques are also used to measure the dielectric properties of potato products at elevated temperatures for these frequency ranges. Both measurement techniques are also used to study the effect of storage temperature on the dielectric properties of Saturna raw potato. For this part of the study, it is concluded that the microwave measurement techniques are unable to discriminate between potatoes that had a storage history of different temperature profiles. On the other hand, waveguide cells and open ended coaxial probes are able to measure the dielectric properties of raw potato, partial cooked fried potato and fried potato at the 500 MHz to 1 GHz and 2.4 GHz to 3.5 GHz frequency range. The measurement results show that both dielectric constant and loss values of fried potatoes decreased with frying time, due to the reduced moisture content during the frying process. Furthermore, the dielectric loss behaviour of raw and fried potatoes is dominated by the effect of the ionic conductivity at frequencies lower than 1 GHz. An apparatus has been designed and built in order to measure the dielectric properties of potato for both frequency ranges as a function of temperature. In the subsequent measurements it is found that the dielectric properties of potato products at elevated temperatures also depend on frequency and moisture content. For high moisture content potato (~> 70 %), at 2.45 GHz both the dielectric constant and loss are found to decrease with temperature, whereas at 915 MHz the dielectric constant decreases but the loss increases for the moisture content above 30%. For the intermediate moisture content (10%<MC<70%), all dielectric properties increase with temperature at the microwave heating frequencies 2.45GHz, whereas at 915 MHz all the dielectric properties increase with temperature for the moisture content range 10% to 30%. The increase in dielectric properties with temperature is small and marginal for fried potatoes with low moisture content (< 10 %). It is therefore apparent that moisture content is the primary factor in detecting the complex permittivity of potato products.
70

Koexistence systémů LTE a LoRa v ISM pásmu 2.4 GHz / Coexistence of LTE and LoRa in the 2.4 GHz ISM band

Potočňak, Martin January 2019 (has links)
This diploma thesis deals with the study and measurement of coexistence scenarios that can occur between the LTE and LoRa systems in the unlicensed ISM band 2.4 GHz. A common radio frequency band in which LTE and LoRa systems can coexist is defined. An appropriate laboratory measurement is proposed and realized, allowing automatized measurement of the defined coexistence scenarios. For this purpose, a personal computer, professional measurement equipment and software MATLAB are utilized. Functionality of the proposed concept is verified by extensive measurements. The obtained results are graphically shown and discussed in detail.

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