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1
Xia, Wenlin. "Diplexers and multiplexers design by using coupling matrix optimisation." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5814/.
Full textAbstract:
Microwave filters and multiplexers are used in many application areas and have been studied for decades. However, with increasing demands on communications and radar systems more complex filters are required which not only have superior performance but also are required to be small and lightweight. This thesis looks at new techniques in microwave filter design to achieve these aims. Coupled resonator circuits are of importance for design of RF/microwave narrow-band filters with any type of resonator regardless its physical structure. The coupling matrix is used to represent the coupled resonator circuit. Each matrix entry value refers to a physical dimension of the circuit. The response of the circuit can also be calculated by using the coupling matrix. Different methods are developed to generate the coupling matrix. This thesis presents designs of the coupled resonator based diplexers and multiplexers by using the coupling matrix local optimisation technique. The design procedures and measurement performance of 3 X-band (8.2-12.4 GHz) rectangular waveguide circuits, including a 10th order diplexer, a 4th order diplexer with cross-couplings and a 4-channel multiplexer, are presented. A novel computer-aided physical structure tuning technique, called Step Tune method, is also presented in this thesis.
2
Zayniyev, Damir. "Development of planar filters and diplexers for wireless transceiver front ends." Thesis, University of Westminster, 2010. https://westminsterresearch.westminster.ac.uk/item/908q7/development-of-planar-filters-and-diplexers-for-wireless-transceiver-front-ends.
Full textAbstract:
The central theme of this work is the design of compact microstrip bandpass filters and diplexers and the investigation of applications of these circuits in integrated transceiver RF front-end. The core of this thesis therefore presents the following stages of the work: - Analysis of coupled pseudo-interdigital resonators and lines; formulation of approximate transmission zero conditions and the investigation of coupling between these two resonators and related structures. - Development of compact, low loss and high selectivity microstrip pseudointerdigital bandpass filters. The design procedure of the filter consists of three simple steps, starting from the design of a parallel-coupled bandpass filter using the image parameter method applied to coupled microstrip lines. The development of compact microstrip diplexers composed of these filters uses the optimized common-transformer diplexing technique. An experimental verification of the developed filters and diplexers is made. - Investigation of the use of stepped impedance resonators (SIR) for the design of pseudo-interdigital bandpass filters with advanced characteristics. The design of compact dual-band filter using SIR. The investigation of possible improvement of the stopband of bandpass filters using bandstop generating structures. The application of SIR, defected ground structures (DGS), spur-lines, and opencircuited stubs in the design of compact bandpass filters with improved stopband. - The application of the proposed filters and diplexers in the design of integrated antenna filters and antenna diplexers. Improvement of performance of patch antennas, such as suppression of spurious harmonics of single-band antenna and improvement of bandwidth and selectivity of dual-band antenna, as a result of integration with filters. Separation of antennas’ bands and reduction of component count in integrated antenna diplexers
3
Cifola, Lorenzo. "Design of high frequency reconfigurable components for space and defence applications." Doctoral thesis, Università Politecnica delle Marche, 2013. http://hdl.handle.net/11566/242685.
Full textAbstract:
I moderni sistemi di comunicazione spaziali e militari sono chiamati a presentare un elevato livello di
flessibilità, al fine di rispondere efficacemente ai cambiamenti nelle richieste degli utenti (in termini di
copertura, distribuzione delle frequenze, larghezza di banda) o essere compatibile con protocolli di
comunicazione basati su un’allocazione dinamica delle frequenze.
Il lavoro svolto nell’ambito del dottorato di ricerca è incentrato sulla ricerca e sviluppo di nuove architetture,
topologie circuitali e geometrie di componenti passivi che consentano di ottenere strutture fisiche le quali,
combinate con elementi di sintonia disponibili in commercio, siano adatte per la realizzazione di componenti
riconfigurabili come filtri, diplexer e antenne.
La prima parte riguarda il progetto di un filtro agile di potenza in banda UHF, compatibile con protocolli di
comunicazione di tipo Frequency Hopping, basato sulla combinazione di una cavità risonante di tipo TEM
non uniforme e dispositivi elettronici utilizzati per la sintonia.
Nella seconda parte il concetto di riconfigurabilità è stato applicato nella progettazione di antenne phasedarray
caratterizzate da proprietà di selettività in frequenza. A partire da una filtenna phased-array di dipoli
connessi progettata in banda X, è stata implementata una tecnica efficace per la realizzazione del matching
adattativo e per la reiezione del modo commune, necessari per la scansione sul piano E. Successivamente, è
stata effettuata la progettazione di una filtenna phased-array riconfigurabile basata su patch alimentati tramite
slot. Inoltre, è stata implementata a livello di antenna una tecnica per la reiezione delle armoniche superiori.
Riconfigurabilità in frequenza è stata inoltre introdotta a livello di antenna in modo da garantire la copertura
dell’intera banda X radar ([8.5 – 10.5] GHz).
La terza parte riguarda il progetto di un Dual-Manifold Feed Diplexer con canali indipendentemente
sintonizzabili. A partire da un articolo di Rhodes, è stato sviluppato un prototipo circuitale caratterizzato da
corrispondenza diretta con la relativa struttura fisica. Inoltre, il prototipo del diplexer di Rhodes è stato
esteso, rendendolo in grado di supportare per ciascun canale la sintonizzabilità della larghezza di banda.<br>Nowadays, modern space and defense communication systems are called to present a high level of flexibility
in order to efficiently response to changes of the business cases (coverage, frequency plane, bandwidth) or be
compliant with communication protocols based on dynamic frequency allocation.
This Ph.D. work is focused on the investigation and development of new architectures, circuit topologies and
geometries of passive components in order to obtain physical structures that, in combination with
commercial tuning elements, are suitable for the realization of reconfigurable components like filters,
diplexers and antennas.
The first section deals with the design of an UHF high power electronically tunable filter, compatible with
Frequency Hopping communication technique, based on the combination of non - uniform TEM resonant
cavities and active tuning devices.
In the second section reconfigurability concepts have been introduced in the design of phased-array antennas
with inherent frequency selectivity properties. Starting from an X-band phased array filtenna of connected
dipoles, an effective strategy for the adaptive matching and common-mode rejection for E-plane scanning
has been implemented. Then, the design of a frequency reconfigurable phased-array filtenna based on slotfed
patches as radiating element has been carried out. Furthermore, higher harmonics suppression has been
also achieved by implementing spurious rejection mechanisms at the antenna level. Frequency
reconfigurability has been implemented on the radiating elements in order to make the antenna capable to
cover the entire radar X-band.
The third area deals with the design of a Dual Manifold Feed Diplexer with Interacting Independently
Tunable Channels. Starting from a promising work of Rhodes, a prototype level circuit with close
correspondence to the physical realization has been developed. Furthermore, Rhodes' diplexer model has
been extended in order to make each channel capable to be independently tuned both in mid-band frequency
and bandwidth.
4
Karlsson, David. "Konstruktion och utvärdering av diplexer." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2783.
Full textAbstract:
<p>The report descripbs how a diplexer for a hybrid analog/digital filterbank has been constructed and tested. A diplexer divides the frequency band into two different bands that do not who doesn't overlapp each other. The sampling rate for the two ADC:s is 80 Msps, and therefore it is advantage to have zero at 80 MHz. The reason for this is that a proposed class of hybrid filterbanks with very good quality requires a zero at or close the sampling frequency to work well. </p><p>The diplexer was made in three versions. The first didn't work since the choosen inductance self resonance frequency was to low and by the same range as the filters bandwidth. The second version had to much losses, which resulted in attenuation at 80 MHz, which was to small. The third version was made in two differents layout. </p><p>To the diplexer it was also made a test tool in Labview, through that one gets the magnitude ande phase functions. </p><p>The results show that the magnitude function is good for version 3.0 and for version 3.1, and that the losses are low. It depends also on that the choosen components have a high self resonance frequency. There can't been shown any differences between these two, thus is is difficult to judge if one is better then an other.</p>
5
Štěpánek, Michal. "Návrh diplexeru na bázi koaxiálních rezonátorů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-219960.
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This thesis deals with the analysis of coaxial cavity filters and synthesis of generic topology of these filters. Transfer function comes out the synthesis, which is based on low-pass prototype and similarity with real structure. The next aim of this thesis is to build the basic software for coaxial cavity filters synthesis from engaged characteristic parameters of the filter. This work also includes the analysis of coupling matrix synthesis based on transfer function, where we can use direct coupling or cross-coupling between resonators. The last point is focused on the diplexer filter based on specified parameters and obtained coupling matrix. Entire diplexer model is optimized using Tuning-Space Mapping method.
6
Randell, Damian P. "Integrated antenna diplexer for mobile communications." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402528.
Full textAbstract:
The rapid growth in second generation mobile telecommunications has resulted in the design of the third generation mobile telecommunication system together with proposals for the fourth generation system. Much of this has been driven by consumer requirements for a global telecommunications system, allowing connection from anywhere around the world and offering data rates that facilitate access to a range of multimedia services. Therefore, continual research into mobile handsets, improving standards and delivering smaller, lower cost devices, is required. The work presented reviews the different mobile technologies and highlights trends in design and application, presenting research into new configurations of RF front-end systems and antennas for mobile communications, specifically the third generation mobile telecommunication system. Developments in the integration of digital circuits has dramatically reduced handset sizes in recent years. However, the same progress has not been seen within RF circuitry. This work, therefore, investigates the properties of microstrip patch antennas for use within mobile handsets and the development of an integrated diplexer antenna. Having reviewed microstrip filters, further designs for a diplexer are also presented. The limitations of these designs are investigated and solutions proposed.
7
Steyn, Werner. "CAD-based iris design procedures for multi-mode coupled cavity devices." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52723.
Full textAbstract:
Thesis (PhD)--Stellenbosch University, 2002.<br>ENGLISH ABSTRACT: Multi-mode coupled cavity filters have been the mainstay of commercial satellite
communications systems since their introduction in 1970. Multi-mode filters use more than
one resonant mode in a single cavity resonator, thereby reducing the size and weight of the
filter. This is especially advantageous for satellite applications where the size and weight of
the communications payload must be minimised. The use of more modes also increases the
complexity of the filter design.
Iris design plays an integral part in the design of multi-mode coupled cavity filters. Currently,
irises are mostly designed using either the small aperture theory derived by Bethe, or a
standard numerical technique. A recent study comparing these two techniques shows that
approximations made in standard correction factors applied to small aperture theory, can lead
to unacceptable errors. While numerical techniques are clearly required for the accurate
design of complex irises, the standard numerical technique is only suited to the design of
relatively simple iris structures.
This dissertation presents three new CAD procedures for the design of irises in multi-mode
coupled cavity devices. The new procedures are verified by numerical examples and
measurements.
Two new multi-mode coupled cavity devices were designed and tested using the CAD
procedures developed in this work. The first is a new diplexer structure that realises two
fourth order Chebyschev filter channels in three quadruple-mode cavities. Through correct
placement and accurate design of irises, channel isolation was increased beyond that of
existing multi-mode diplexer structures.
The second application is the development of a new coupling structure for the replacement of
coupling and tuning screws. A third order triple-mode cavity filter, including this new fixed
coupling element, was designed using the CAD procedures developed in this dissertation.<br>AFRIKAANSE OPSOMMING: Multi-modale gekoppelde resoneerder filters word reeds vanaf die eerste verskyning van
kommersiele sateliet-kommunikasiestelsels in 1970 gebruik. Vir hierdie toepassing is die
fisiese grootte en massa van die filters in die kommunikasiestelsels van groot belang. Multimodale
filters gebruik meer as een resonante modus in ‘n golfgeleier resoneerder om die
fisiese grootte en massa van die filter te verminder. Hoe meer resonante modusse in een
golfgeleier resoneerder, hoe kleiner en ligter die filter. Die gebruik van meer modusse
kompliseer egter die ontwerp van die filter.
‘n Baie belangrike aspek van multi-modale filterontwerp is die ontwerp van die irisse wat die
golfgeleier resoneerder skei. Die irisse word tans ontwerp, of deur middel van Bethe se klein
iris teorie, of met die gebruik van ‘n standaard numeriese metode. ‘n Onlangse studie toon
aan dat sekere standaard toevoegings tot Bethe se teorie, benaderings bevat wat tot foutiewe
iris ontwerp kan lei. Numeriese metodes is dus noodsaaklik vir akkurate iris ontwerp.
Hierdie studie wys egter dat die bestaande numeriese tegnieke beperk is tot die ontwerp van
relatief eenvoudige irisse.
Hierdie proefskrif bied drie nuwe rekenaargesteunde ontwerpsprosedures vir die doeltreffende
ontwerp van verskillende klasse irisse in multi-modale golfgeleier resoneerder filters. Die
nuwe metodes word getoets aan die hand van numeriese voorbeelde, en/of gemete resultate.
Twee nuwe komplekse multi-modale golfgeleier resoneerder filter toepassings is ontwerp
deur gebruik te maak van die nuwe ontwerpsprosedures. Die eerste is ‘n nuwe diplekser
struktuur met twee vierde-orde Chebyschev filterkanale in drie golfgeleier resoneerders wat
elk vier resonante modusse ondersteun. Deur korrekte en akkurate plasing van die irisse word
‘n groot verbetering in kanaalisolasie bo ‘n bestaande multi-modale diplekser verkry.
Die tweede toepassing is die ontwikkeling van ‘n nuwe koppelstruktuur vir die vervanging
van die gebruiklike koppel- en aanpassingskroewe. ‘n Derde-orde trippel-modus filter,
gebaseer op hierdie nuwe struktuur, is ook ontwerp deur van die nuwe ontwerpsalgoritmes
gebruik te maak.
8
Sitaraman, Srikrishna. "Modeling, design, fabrication and characterization of miniaturized passives and integrated EM shields in 3D RF packages." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54369.
Full textAbstract:
An innovative structure for thin-film band-pass filters was proposed and analyzed. This structure was employed in the design, fabrication, and development of 3D IPD diplexers on glass substrates with double-side metallization electrically connected by through-vias. Through modeling, design, fabrication and characterization of the WLAN 3D IPD glass diplexers, the proposed filter structure was shown to enable miniaturized and high-performance RF passives. Further, component-level shield structures were developed to provide electromagnetic interference isolation between thin-film passives that are placed less than 100 µm apart. Glass substrates were designed, fabricated and characterized to demonstrate the shield effectiveness of metallized trench and via-array-based shields. The integration of such shields in miniaturized WLAN RF modules enables up to 60dB EM isolation in the frequency range of 1- 20GHz. Advanced RF module technologies based on 3D IPAC concept were designed and demonstrated with ultra-thin low-loss organic and glass substrates, integrating the proposed WLAN actives with miniaturized diplexer and EM shields. Double-side integration of such high-performance components on ultra-thin glass substrates enables up to 8x volume miniaturization including more than 3x reduction in area. Thus, the advanced components demonstrated in this research, vis-a-vis miniaturized diplexers and component-level EMI shields; integrated with actives in ultra-thin glass substrates using the 3D IPAC concept, can enable highly-miniaturized smart systems with multiband wireless communication capabilities.
9
Taiby, Awrang. "WIDEBAND, LOW-LOSS, HIGH-POWER HANDLING DIPLEXER FOR AIRBORNE EARLY WARNING (AEW) SYSTEMS." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/745.
Full textAbstract:
Airborne Early Warning (AEW) systems rely on rotary couplers (RC) to interface rotating antenna elements on aircraft exteriors with stationary onboard systems. The demand for additional channels in new generation AEW systems increases the complexity of rotary couplers significantly. On the other hand, if signals in separate frequency bands use the same channel, existing AEW designs could incorporate additional channels with only minor changes. Passive RF diplexers can accomplish this task. Required characteristics include low-loss (<0.5dB), wideband (4.4:1), and high-power (>6kW) handling capability. Two diplexer candidates are synthesized and characterized with the aid of a commercial circuit simulation package that includes a 3D full-wave EM solver. A semi-lumped coaxial and a digital elliptic diplexer are proposed, both of which have theoretically low-loss and acceptable VSWR characteristics. However, only the latter diplexer meets operating requirements without the excessive tuning or analysis required by the former. Further studies of the semi-lumped diplexer characteristics may make it useful in other applications.
This thesis defines diplexer design goals, provides a brief introduction to filter theory, and compares performance characteristics of the semi-lumped and digital elliptic diplexers. Simulation results for both designs demonstrate that the digital elliptic diplexer is an optimum solution.
10
BALDELLI, MARCO. "Innovative microwave devices for space applications." Doctoral thesis, Università Politecnica delle Marche, 2016. http://hdl.handle.net/11566/243076.
Full textAbstract:
Gli obiettivi di questo studio sono l'ideazione e il progetto di componenti a microonde innovativi, destinati in particolare alle applicazioni satellitari. Due sfide che i progettisti di queste architetture si trovano attualmente ad affrontare sono la necessità di ridurre peso e volume dei satelliti, e l'introduzione della capacità di riconfigurazione. Entrambi i requisiti puntano alla riduzione dei costi dei payload, e all'estensione della loro vita, intesa come intervallo di tempo durante il quale il payload rimane operativo.
Il primo argomento discusso in questa tesi è il progetto di una classe di accoppiatori direzionali a microonde, che permetta la riduzione del peso del satellite fondendo le due reti di beam-forming che alimentano le due polarizzazioni ortogonali delle antenne in una singola struttura sovramodata. Questa classe di componenti è nota in letteratura come a "doppia polarizzazione". Degli accoppiatori a quattro-porte che supportano due polarizzazioni furono già introdotti nel 1997. In questo lavoro, vengono definite delle linee guida di progetto per questi componenti, basato sulla scelta ponderata del tipo di elementi di accoppiamento al fine di garantire un elevato accoppiamento, mantenendo l'isolamento tra le polarizzazioni ortogonali.
Al momento della stesura di questo lavoro non sono reperibili, sia nella letteratura internazionale che nelle banche dati dei brevetti, esempi di accoppiatori direzionali a doppia polarizzazione con un numero di porte superiore a quattro. In questa tesi, viene descritto un accoppiatore direzionale a 6 porte, che supporta la doppia polarizzazione. Questo componente innovativo è stato inizialmente progettato con un simulatore elettromagnetico commerciale, ed in seguito ne è stato realizzato un prototipo con il quale sono stati verificati i risultati ottenuti.
La seconda parte di questo studio riguarda dei diplexer riconfigurabili, dove la frequenza centrale dei canali può essere posizionata in modo arbitrario, fino al caso limite di canali contigui. Viene descritto e migliorato un prototipo circuitale di diplexer riconfigurabile basato sul concetto di 'dual-manifold' proposto da J. D. Rhodes. Inoltre, tale prototipo circuitale è stato adattato ad una realizzazione fisica in guida d'onda, appropriata per le applicazioni spaziali.
Il progetto di questo componente ha richiesto l'introduzione di filtri composti di cavità sovramodate, in particolare cavità cilindriche operanti con il modo TE011, al fine di garantire basse perdite di potenza. Il progetto efficiente di tali strutture si è rivelato un compito impegnativo. Pertanto, questo studio comprende anche la descrizione di una tecnica innovativa per la segmentazione di filtri composti da cavità sovramodate, che può essere impiegata per predire in modo efficiente la risposta finale del filtro, riducendo la complessità delle simulazioni elettromagnetiche richieste. In tal modo, il progetto di queste strutture complesse risulta un compito più semplice.<br>The aim of this study is the ideation and design of innovative microwave components, particularly suited for satellite applications. Two actual challenges in the design of architectures for this kind of applications are the need to reduce the overall mass of the satellites, and the introduction of reconfigurable capabilities. Both the requirements aim to reduce the costs of the payload, and to extend its lifetime, that is the interval of time the payload remains operative.
The first topic covered by this thesis is the design of a class of microwave passive directional couplers, that allows for the reduction of the mass of a satellite by fusing the two beam forming networks feeding each polarization of the double-polarization antennas into a single overmoded structure. This class of components has been referred as "dual-polarization" in the literature. Four-port directional couplers supporting two polarizations were already introduced in 1997. Here, the design guidelines of a dual-polarization directional couplers are defined. The design is based on a judicious choice of the coupling elements in order to guarantee acceptably large coupling and high isolation between orthogonal polarizations. Then, the case of a 6-port directional couplers is considered. No examples of dual-polarization directional couplers with more than 4 ports have been reported so far, both in the international literature and in the patent repositories. In this thesis a 6-port directional coupler working in double polarization is described. The novel component has been designed with commercial full-wave electromagnetical solver, and a prototype has been manufactured and tested.
The second topic concerns diplexers whose channel centre frequencies can be arbitrarily positioned, resulting in contiguous and non-contiguous channel spacing. A circuit prototype of tunable diplexers based on the ‘dual-manifold’ concept, proposed by J.D.Rhodes, has been considered and improved. Moreover, the circuital prototype has been adapted to a physical realization in waveguide, suitable for space applications.
The design of this component required the introduction of filters made of overmoded cavities, such as circular cavities operating in the TE011 mode, to guarantee low power losses. The efficient design of such structures is a challenging task. Therefore, this study also comprehends the description of a novel technique to segment a filter made of overmoded cylindrical cavities, that can be used to efficiently predict the overall response of the filter. The method reduces the complexity of the full-wave electromagnetic simulation to be performed, thus making easier the design of these complex structures.
11
Gouget, Pierre. "Etude de circuits hyperfréquences utilisant la jonction inhomogène ligne à fente, ligne microruban : application à l'intégration de filtres et de diplexeurs." Bordeaux 1, 2004. http://www.theses.fr/2004BOR12887.
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L'étude comporte quatre chapitres. Le premier permet de situer le sujet par rapport à la problématique de la miniaturisation des circuits électroniques dans le domaine des télécommunications hyperfréquences et d'exposer le cadre technologique de l'étude. L'association verticale des deux types de guidage (ligne microruban, ligne à fente) exploitée dans les chapitres suivants est abordée. Le deuxième chapitre est consacré à la modélisation des transitions entre ces deux types de lignes de transmission. La notion de jonction inhomogène permettant d'ajuster la bande passante de la transition est ainsi étudiée. La relation entre bande passante de la jonction et dimensionnement technologique des stubs est développée. Le troisième chapitre traite de la mise en œuvre de méthode d'optimisation pour la conception de structures multicouches utilisant des jonctions inhomogènes. Une approche technologique des structures filtrantes est proposée et les outils logiciels d'aide à la conception développés dans le cadre d'une optimisation par la méthode des plans d'expérience sont présentés. Les performances du modèle proposé sont comparées à celles d'autres modèles ainsi qu'aux résultats disponibles dans la littérature. Enfin dans un dernier chapitre, des applications utilisant la jonction inhomogène permettent de valider les outils d'optimisation et de simulation développés. L'auteur traite successivement de la réalisation sur substrat d'alumine d'un filtre passe-bande (10-12GHz) puis développe plusieurs topologies de diplexeurs (voie basse : 8 – 10,8GHz et voie basse 11,2 – 14GHz). Les performances des circuits réalisés, en accord avec les spécifications initiales, permettent de valider l'approche de conception et d'optimisation. Pour finir une prospective en terme de filtre ajustable est suggérée<br>Four chapters compose this study. The first one situates the research subject into the high frequencies telecommunications domain with the links to the increasing of electronic circuits miniaturisation and the technological features used in the study. The vertical association of two types of wave guide lines (microstrip line and slot line) used in the following chapters is presented. The second chapter deals with the model of microstrip to slot line transition. This study is completed by a new inhomogeneous junction concept with tuneable bandwidth. The relationship between junction's bandwidth and technological dimensions of its stubs is developed. In the third chapter, an optimisation method for multi layer structures using inhomogeneous junction is developed. A technological approach of filtering structures is proposed and CAD (circuit aided design) tools based on DOE (design of experiment) optimisation method are presented. The model performances are compared to other models and literature results. Finally in a last chapter, structures using the inhomogeneous junctions validate the previous optimisation and simulation tools. The author treats successively several realisations on an alumina substrate: a band pass filter (10 - 12GHz) and several diplexer topologies (low frequencies way: 8 - 10. 8GHz and high frequencies way: 11. 2 – 14GHz). The features of these realisations, in conformity with the required specifications, validate the conception and optimisation approach. Finally, an expectation in terms of tuneable filter is planned
12
Hansmann, Esti Mari. "An investigation of coupling mechanisms in narrowband microwave filters." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2496.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2008.<br>The design of an aperture-coupled coaxial diplexer for R-band, is presented. To
improve the ease of tuning, a tuning procedure for the diplexer with the aid
of a MATLAB application with graphical user interface, is developed. Final
experimental results show good agreement between the circuit model and the
physical structure. Final measurements of the diplexer structure achieved 18.83 dB
and 21.52 dB return loss in the lower and upper frequency band respectively and
insertion loss of 0.58 dB and 0.61 dB was measured for the two frequency bands.
Isolation were measured as 74 dB at 2.01 GHz and 84 dB at 2.17 GHz
The accuracy of two techniques for determining coupling coefficients in coaxial
and waveguide resonators are investigated. One method is the Eigenmode Method
for determining the coupling coefficients in a physical resonator and the other the
circuit model representation, utilising inverters to represent the coupling between
resonators. Results showed that marked differences occur when using the three
different inverter configurations to enable filter dimensioning for a given coupling
coefficient.
Four waveguide filters, utilising posts and irises respectively, are designed using
dimensions obtained from the three inverter configurations as well as the Eigenmode
method for a certain coupling coefficient.
13
Alicioglu, Bulent. "A Novel Method For 2-18 Ghz Switched Multiplexer Design." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614931/index.pdf.
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A novel topology is developed and used to design a switched multiplexer. In the new topology there are two noncontiguous switched multiplexer modules containing the channels 2-4 GHz, 6-8 GHz, 10-12 GHz and 14-16 GHz named as odd channels and 4-6 GHz, 8-10 GHz, 12-14 GHz and 16-18 GHz, named as even channels to improve isolation between adjacent channels. The input signal is split at input into the two multiplexer and the outputs of the multiplexers are combined by 2-18 GHz power dividers. The input and output multiplexers are combined through switch + Low Noise Amplifier + attenuator blocks which are also used for amplitude equalization. The input/output multiplexers are designed using a novel technique that transforms a contiguous manifold multiplexer into non-contiguous multiplexers with 2 GHz bandwidth to form guard bands between channels to improve isolation. The HP outputs of the channels are split by LP-HP diplexers with corner frequencies at the centers of the channels. Then only the LP outputs of these diplexers are fed to the output to form a non-contiguous multiplexers. The HP outputs of LP-HP diplexers are terminated in 50 ohms. The incorporation of LP-HP diplexer to form noncontiguous channels is a novel approach which avoids interaction of channels. The diplexers forming the switched multiplexer are designed using a novel approach which incorporate open circuited parallel coupled line as diplexing element. This structure acts as an integral part of the diplexer and contributes its performance. The LP-HP diplexers are designed and fabricated successfully in suspended stripline. The implemented LP-HP diplexers are then combined to form the even and odd channel multiplexers. The measured results of the individual diplexers are then combined with attenuator+Amplifier blocks to form the circuit model of the targeted switched multiplexer yielding successful performance. Thus, the design is complete and ready for the realization of a switched multiplexer.
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Hu, Xin. "Some studies on metamaterial transmission lines and their applications." Doctoral thesis, Stockholm : Skolan för elektro- och systemteknik, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10126.
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Ghribi, Adnan. "Composants millimétriques supra-conducteurs pour la mesure de la mesure de la polarisation du fond diffus cosmologique et application à l'interférométrie bolométrique." Phd thesis, Université Paris-Diderot - Paris VII, 2009. http://tel.archives-ouvertes.fr/tel-00726118.
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La mesure du fond diffus cosmologique est depuis les années 1980 au centre des préoccupations majeures de la cosmologie observationnelle. Aujourd'hui, le défis est la détection des modes B de polarisation de ce rayonnement. Ceux-ci constituent une signature des ondes gravitationnelles primordiales. Afin de pouvoir atteindre cet objectif, nous avons besoin d'instruments offrant des performances exceptionnelles autant au niveau des composants que de l'architecture. Cette thèse s'intéresse de près à des composants planaires supra-conducteurs conçus pour être intégrés dans ces instruments : en particulier des filtres, des diplexeurs de polarisation et des modulateurs de phase. Ces composants pourront être utilisés dans l'interférométrie bolométrique, une architecture de détection particulièrement novatrice. L'expérience QUBIC dédié à l'observation des modes B est basé sur une telle architecture.
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Lai, Felix, and 賴忠沅. "Design and Implementation of Microwave Diplexers." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/43801745948006608616.
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碩士<br>國立中央大學<br>電機工程研究所<br>91<br>In the thesis, the designs of the diplexers conforming the standards of IEEE802.11b、IEEE802.11a or HiperLAN2 have been discussed. To design a diplexer, the filters corresponding each frequency channel are first developed and then combined using T-junction. Many different types of filters are designed in the thesis. The behaviors of the presented circuits are all studied not only numerically using IE3D electromagnetic simulator, but also experimentally by circuit measurements. Good agreement has been obtained between simulations and experimental results. The effects of the substrate material on the quality of the circuits are also discussed.
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Shojaei-Asanjan, Desireh. "High Power Analysis of Filters and Diplexers." Thesis, 2012. http://hdl.handle.net/10012/7199.
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The ever-increasing popularity and usage of communication devices has resulted in power density becoming more demanding due to crowding of frequency spectrums and narrowing of bandwidths. Consequently, the power-handling capability of filters has emerged as an important research area. With the size and mass of filters shrinking to accommodate the needs of the latest technology, designing narrowband filters necessitates the operation of filters close to their maximum power capacities. Hence, there is an urgent need to properly measure and estimate power-handling capability in filter-based products such as satellite multiplexers and wireless diplexers.
In this research, the design of filters and diplexers capable of handling higher power was investigated using modifications of available methods to predict the maximum input power that a filter can handle before breakdown. This method was utilized to improve the power-handling capability and quality factor of the conventional coaxial resonator while avoiding time-consuming EM simulations.
A novel coaxial resonator configuration was proposed using this method and the performance of suggested configuration was validated by designing 2-pole filters using both conventional and novel configurations. A 4-pole chebyshev filter was also designed and realized using the proposed configuration, and a power-handling analysis utilizing HFSS was compared with that of the estimated value.
A novel approach in the design procedure of coaxial diplexers was proposed that provided a faster design method using step-by-step group delay matching of EM simulation results with a diplexer equivalent circuit. A method for predicting air breakdown was also applied to the diplexers to determine maximum power-handling capability.
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Hsu, Wei Hong, and 許維宏. "Filters and Diplexers Designs of Suspended Stripline." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/03098755669398835697.
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碩士<br>國立彰化師範大學<br>電信工程研究所<br>97<br>In this thesis, we propose a novel compact SSL structured BSF. These series- and shunt-tuned modules can individually tune the circuit’s zero frequencies without affecting others. The developed equivalent circuit is successfully used to analyze the circuit performance. A very good agreement between the measurement and the simulation is observed. A wider BW BSF can be achieved by cascading more sections of the frequency-tuned blocks. It is believed that this BSF design should be able to find many applications in modern wireless communication system An experiment is conducted and a good agreement between the measurement and the simulation is observed to verify the design.
A novel design of a suspended stripline dual-band bandpass filter using multi-layer technology is also presented. The multi-layer prototype filters is composed of two stepped impedance suspended stripline (SISSL) which proposed in this thesis to build a 2.45/5.2-GHz dual-band bandpass filters (BPFs) with multiple zeros for the WLAN applications. The filter’s characteristics are analyzed by a circuit model of the SISSL and LC lumped elements which are implemented by the suspended stripline. A structure which providing a transmission zero is adopted in each filter to reject the signal of the other filter’s band. This filter has acquired a sharp rejection and consequently, a good selectivity.
In order to design the filters with a better performance, The low-pass and high-pass filters is made up by suspended stripline. Furthermore, a diplexer covering the ultra-wideband (UWB) frequency range is formed by the combination of the low-pass filter and the high-pass filter. Measurements show a good agreement with the simulations.
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Wen, Pi-Hung, and 溫璧鴻. "Design of Balanced BPFs and Balanced-Type Diplexers." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/97712260676088950214.
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碩士<br>國立彰化師範大學<br>電信工程研究所<br>101<br>In this thesis, we first propose a new balanced bandpass filter (BPF) which consists of stepped-impedance slot-line resonators (SISLRs) that are fed by microstrip lines in Chapter 2. The differential-mode (DM) bandpass response can be established because the equivalent half slot-line region has a complete boundary along the plane of symmetry (POS) and hence can resonate as a whole at the desired passband center frequency, whereas the common-mode (CM) transmission response can be attenuated because part of that boundary is open-circuited and thus the slot-line region can no longer resonate as a whole. In addition, the upper DM stopband of the proposed balanced filter is widened by using impedance mismatching between the feeding lines and the resonators for spurious-mode suppression.
In Chapter 3, SISLRs were employed to design a balanced diplexer and a balun diplexer, both of which were realized to channel the 2.45-GHz WLAN and 3.55-GHz WiMAX signals. In the beginning, balanced filters for these two different frequency channels were constructed, each consisting of two coupled slotline resonators and four fork-like feeding lines. Next, balanced and balun diplexers with good DM transmission and isolation responses and large CM suppression were sought.
In Chapter 4, uniform-impedance resonators (UIRs) and center-grounded UIRs (CGUIRs) are proposed to design a balanced diplexer and a balun diplexer. These UIRs were first employed to construct two four-port balanced BPFs, which were subsequently combined through two T-junctions to form a balanced diplexer. The balan diplexer is realized by removing one of the two T-junctions from the balanced diplexer and then by fine-tuning the remaining structure.
In Chapter 5, we summarize the research work completed in the thesis and propose ideas for further study.
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VANIN, FELICE MARIA. "Waveguide bandpass filters and diplexers – analysis and synthesis." Doctoral thesis, 2011. http://hdl.handle.net/11573/918091.
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Xu, Wei-Qin, and 徐偉欽. "Quasi-Lumped Elements Composed Planar Filters and Diplexers Design." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/81339048633561972089.
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碩士<br>國立彰化師範大學<br>電子工程學系<br>96<br>In this thesis, we propose a novel design of a bandpass filter using combined coplanar waveguide (CPW) and microstrip. The filter is composed of the lumped elements implemented by the CPW structure and section microstrip line. Zeros have been implanted in circuit design to reject adjacent channel interferences. This filter has acquired a very sharp rejection and consequently, a good selectivity. The stopband bandwidth is also very wide in this filter design.
A novel design of a UMTS diplexer using these filters is also presented. The diplexer is composed of two bandpass filters which termed as the transmit (Tx) and receive (Rx) filter. The filter’s characteristics are analyzed by a circuit model of the LC lumped elements which are implemented by the CPW and microstrip. A structure which providing a transmission zero is adopted in each filter to reject the signal of the other filter’s band. The two filters are connected in a parallel-cascade configuration and a microstrip is used to couple the I/O signals from/to the filters.
In order to design the bandpass filter with a better performance, The low-pass and high-pass filters is made up by suspended stripline. Furthermore, a bandpass filter covering the ultra-wideband (UWB) frequency range is formed by the combination of the low-pass filter and the high-pass filter. Measurements show a good agreement with the simulations.
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TSENG, PO-SHIANG, and 曾柏翔. "Design Of High Yield Diplexers Requiring Fewer Tunable Devices." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/nbxm85.
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碩士<br>國立臺北大學<br>通訊工程研究所<br>107<br>The related products of wireless communication system is more and more important in our daily life.
Wireless TV, wireless network and mobile phone has become an indispensable equipment for people every day, the demand of wireless communication products is in exponential growth. Nowadays, Frequency-division multiplexing(FDM) is still a very common and practical transmission method.
A typical diplexer consists of a low-pass filter and a high-pass filter with a common port and two output ports that operate in different bandwidth.
The purpose of this paper is to produce a diplexer printed circuit that meets the specifications, the size of the product, and the number of tunable devices meet the system requirements. The goal is to reduce the number of components that need to be tuned on the circuits to three and hope to achieve 95% yield in the hundreds of circuits. Reducing the number of components can reduce production time and labor costs, but the disadvantage is that it is not adjustable. When such components are placed in sensitive locations or have manufacturing errors, it may cause changes in circuit characteristics. Therefore, how to use a spiral inductor to reduce the number of tunable devices and reduce the position of sensitive components in the circuit is extremely important.
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Tsai, Wan-Ling, and 蔡宛伶. "Multi-band Filters and Diplexers Design by Multi-Mode andFrequency Transformation." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/59157066321129803693.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>98<br>This thesis aims at the improvement in multiband filters and diplexers by proposing two kinds of new design concepts. Based on the SIW (Substrate Integrate Waveguide)implemented on LTCC (Low Temperature Co-fired Ceramics), the first part designs a tri-band filter and elaborating the concept, two diplexers. The second part designs two microstrip quad-band filters.
The LTCC SIW tri-band filter in the first part utilizes the concept of mode orthogonality in the rectangular cavity, thus the coupling coefficients between modes in two cavities can be controlled independently by the location of slots. Furthermore, multiple modes can be excited simultaneously with the proper feeding position. If one of the modes is applied by split-type dual-band response, a tri-band filter with improved band allocation can be realized with minimized number of resonators. Furthermore, two diplexers are designed by exploiting the multi-modal orthogonality. Two channel can share the same input resonator since two modes can be excited simultaneously;
therefore the matching network is not needed in this structure. Also, two orthogonal slots opened in the common output resonator are designed to extract two modes independently and yet with good isolation.
The second part proposes a general idea of frequency transformation for multiband filter design. The poles and zeroes of a single band response are transformed to poles and zeros of a multi-band response according to the cutoff frequency of each band. Two microstrip quad-band filters are presented to verify the concept.
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Chen, Hsien-Ting, and 陳咸廷. "Analysis and Design of Low Temperature Cofired Ceramic Filters and Diplexers." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/40097169130299346490.
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碩士<br>國立中正大學<br>電機工程研究所<br>92<br>In this thesis, I use the image parameter method is adopted to analyze and design LTCC bandpass filters and duplexers for WLAN and GSM/DCS applications. The circuits have better stop-band attenuation with addition of transmission zero without increasing the circuit complexity of the filter. Each image cell is first analyzed and the formulas for its component values are obtained subject to the desired specifications. Finally, the circuits are constructed in a 3D LTCC mutilayer structure and slight adjusted by 3D full-wave EM simulator. The designed device will reduce the area substantially for the feature of vertical integration of LTCC. The measured results confirm the proposed circuit structure and design procedure.
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Chang, Jhih-Hong, and 張誌宏. "Design of Balanced Bandpass Filters and Diplexers Using Stepped-Impedance Resonators." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/65856584848842211309.
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碩士<br>國立彰化師範大學<br>電信工程研究所<br>101<br>The main objective of this thesis is the study and design of balanced bandpass filters (BPF) and diplexers. The research work is divided into three parts. For the first part, a balanced dual-band BPF composed of symmetrical microstrip feeding lines and a slotline resonator was designed. Tri-section stepped-impedance slot-line resonator (TSSISLR) which allows the first and the second harmonic resonant frequencies adjustable was used as the main resonant unit. The distinct differential-mode (DM) and common-mode (CM) characteristics of the plane of symmetry are utilized to achieve good DM response and high CM noise suppression. In addition, to obtain good selectivity, we arranged the slot-line resonator and microstrip feeding lines to form a dual-path (cross-coupled) structure, which allow signals to pass through the two paths, and thus may cancelled out at the output port as they are of the same amplitude and 180 degrees out of phase. By the cross-coupled configuration, transmission zeros can be introduced to both sides of the passband and the selectivity can be increased.
In the second part of the research, we used balanced BPF to design a balanced diplexer with high isolation. The balanced diplexer utilized the T-junction to do the integration of two single-balanced bandpass filters. In this study, the main structure consists of two stages of /4 SIR. We utilize the SIR’s adjustable frequency characteristics to design a wider high-frequency stopband. In the plane of symmetry, the two input ports and the resonator has a connection, while the two output ports don’t, and this does not have any effect in the differential mode operations. The reason is that when the differential mode operation, at the plane of symmetry can be considered as a ground plane, input and output ports are similar, its impact therefore can be ignored. But, when at common mode operations, the circuit symmetry plane can be regarded as a magnetic wall, half circuit of the original resonator from /4 SIR converted to the resonance structure of /2 SIR. Due to the connection between input feed-line and first-stage resonator, the feed-line and first-stage resonator integrate to form a transmission line, the signal is feed into the second stage resonator by the transmission line and then transmit out from the output port, the original differential-mode good impedance match is damaged, causing poor signal transmission and suppression of the common-mode operation.
The balanced BPF and diplexer designed by this research showed that the simulation and measured results are quite consistent. The obtained results show that the theoretical value of differential-mode reflection loss is less than 2 dB, while the common-mode insertion loss in the 1-8 GHz frequency range is greater than 20 dB, isolation is also greater than 35dB. So, the designed balanced BPF and diplexer both have good differenced-mode operation, high common-mode noise rejection and high isolation performance.
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Lu, Lung-Chun, and 盧龍俊. "Broad passband and wide stopband diplexers using asymmetric stepped impedance resonator." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/z3f3mf.
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碩士<br>國立中央大學<br>電機工程學系<br>105<br>In general, the requirement of multiplexers applications, almost all of the multiplexers were used distributing coupling technique to design. Due to the low loading effect from distributing coupling technique, the circuits can obtain many channels without need of complicated matching network. Therefore, thesis presents wideband and wide stopband bandpass filter using tapping technique and asymmetric stepped impedance resonator. By using various dissimilar half-wavelength asymmetric stepped-impedance resonators (SIRs) and shunt open-circuited stubs, a wide stopband is achieved. The higher order mode frequencies can be determined by property choosing a suitable combination of impedance ratio and electrical length ratio of the asymmetric SIR. Parallel-coupled line with a meandering uncoupled section can enhance spurious suppression. And analyze transmission pole, Current distribution and load effect. Finally, on the basis of this structure of the diplexer with wideband and wide stopband characteristics, the bandwidth is reaches about 50 %. The 20-dB stopband extends up to 7.0 f0 the lowest operation center frequency and the isolation is better than 28 dB and the. Based on the design concept, the proposed diplexer is designed and fabricated with good agreement between simulations and measurements.
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Peng, Han Sheng, and 彭瀚陞. "Development of novel miniaturized microstrip diplexers with adopting different types of channel filters." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/tkz4y2.
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Wu, Syu-Sheng, and 吳旭昇. "Multi-Band Integrated Antennas and Diplexers on Printed Circuit Boards and Low Temperature Co-fired Ceramics (LTCC) Filter." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/38841288599840833854.
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碩士<br>國立交通大學<br>電信工程系所<br>93<br>The integrated RF front-end module of communication systems usually only includes a diplexer and two different bandpass filters. As the RF front-end module becomes highly integrated, the integrated design of a dual-band antenna and a diplexer will be in great trends for research and commercial products in the future. In the paper, Ansoft HFSS full wave simulator is used to be the design tool. The purpose of this paper is to propose a new integration design of a dual-band antenna and a diplexer that can be applied to the Wireless Local Area Network (WLAN) system. The dual-band antenna structure proposed by this paper is constructed by the original quarter wavelength (��/4) monopole antenna plus a sleeve structure. This improvement is expected to help obtain the wide bandwidth and dual-band effect. The diplexer is composed of stepped impedance resonator bandpass filter and ��/4 parallel coupled microstrip line bandpass filter. The proposed dual-band antenna structure possesses 22.49% and 32.58% impedance bandwidth under the WLAN band of 2.4 GHz and 5 GHz. The proposed integrated structures of the dual-band antenna and the diplexer can meet the requirements of the 2.4 GHz and 5.2 GHz WLAN systems. Besides, in order to obtain a WLAN bandpass filter with the specific of 2.4GHz, we apply LTCC to effectively process the selected suitable lumped element circuit model of the bandpass filter. The newly designed WLAN bandpass filter will be of small size, of high selectivity and highly integrated.
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Chen, Meng-Hsuan, and 陳孟萱. "Design of W-Band Substrate Integrated Waveguide T Diplexer and Bifurcated Diplexer." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/c65b78.
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碩士<br>國立交通大學<br>電信工程研究所<br>103<br>The design of W-Band Substrate Integrated Waveguide (SIW) T diplexer and bifurcated diplexers are presented in this thesis. To achieve two types of diplexers, we design inductive-post filter for various frequencies. The proposed diplexers involve two types, the T diplexer and the bifurcated diplexer. The advantages of T diplexer are its simple structure and compact size. There is more design variables in the design flow of bifurcated diplexer in order to obtain better response.
The bandwidths and center frequencies of T diplexer are 3%, 81GHz, and 3%, 93GHz, respectively. The center frequencies of three bifurcated diplexers are 81 GHz, 93 GHz and 85GHz, 93GHz and 90GHz, 93GHz, respectively.
The circuits are fabricated using Rogers RT- Duroid 5880TM substrate with thickness of 10 mil, dielectric constant of 2.2, and dielectric loss tangent of 0.002. All of the fabricated circuits are connected to SIW to rectangular waveguide transition and measured by vector network analyzer.
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Peng-Fan, Chen, and 陳鵬帆. "Quasi-Lumped Suspended Stripline Diplexer." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/78028218927428837291.
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碩士<br>國立中央大學<br>電機工程學系<br>103<br>This study proposed an systematic design flow for quasi-lumped suspended stripline diplexer. According to modified circuit model with parasitic effect on high-pass and low-pass filter layout, the diplexer design are accomplished step by step. Practical consideration and fabrication variation are also take into design.
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Chen, Yen-Cheng, and 陳彥程. "V-Band Substrate Integrated Waveguide Diplexer." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/24945690841448703272.
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碩士<br>國立交通大學<br>電信工程研究所<br>104<br>The design of V-band Substrate Integrated Waveguide (SIW) micrrostrip T-junction duplexer is presented in this thesis. Two inductive-post coupled channel filters are combined with microstrip T-junction. Two structures are proposed to improvement the isolation. First, we suppress unwanted signal by using a bandstop filter. The adventage of this method is that even if the frequencies of two channel filters are close to each other the method is still valid. Second, we replace the Chebyshev channel filter with a 3rd order cross-coupled filter that a transmission zero near the edge of the passband is created. The adventage of this method is the small size but as the channels closing to each other the suppression is not as good as the first method.
To explore the relation between isolation and the distance of two center frequencies, two duplexers with center frequency of 60 GHz, 67 GHz and 63 GHz, 67 GHz are studied.
The circuits are fabricated using two kinds of substrates. One is Rogers RT- Duroid 5880TM substrate with thickness of 10 mil, dielectric constant of 2.2, the other one is Rogers RO4350TM substrate with 10 mil, dielectric constant of 3.66. The circuits using Rogers RT- Duroid 5880TM substrate are connected to SIW to a specially designed rectangular waveguide transition and measured by vector network analyzer.
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Chiu, Ching-Kai, and 邱敬凱. "Compact and Tunable Sext-Channel Diplexer." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8mq44w.
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碩士<br>國立交通大學<br>電信工程研究所<br>107<br>This paper demonstrates the design of a second-order tunable duplexer with six channels. It features a tri-mode resonator designed to form a tunable sext-channel diplexer in the form of a second-order filter.
Traditional diplexers or filters require different circuits to implement the system under different requirements. For example, different operating frequencies require circuits with specific specifications. After adding the varactor, all the different requirements of the same specification circuit can be integrated, and the capacitance value of the varactor can be changed by adjusting the voltage to make different operating frequency changes, thereby satisfying the different operating frequencies. The demand can be achieved in a single circuit to meet the needs of different situations. Furthermore, the design of the three-mode resonator can greatly reduce the number of resonators compared with the conventional single-mode resonator. For example, in the present example, the conventional sext-channel second-order diplexer requires twelve resonators. The use of a tri-mode resonator reduces the number to four, significantly reducing the area.
The first chapter is the introduction, the second chapter is the theory introduction, and the third chapter is the introduction of the tunable sext-channel diplexer. In this paper, the direct feed method is adopted, and the filter is combined by T-junction, which needs design matching. Circuit, but only need to connect a fixed capacitor in parallel with the feed line to meet the required external quality and meet the needs of the matching network. Finally, all simulation and measurement data are included. The fourth chapter is the conclusion and outlook.
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Yang, Shie-Chie, and 楊世傑. "Design and Fabrication of Microwave CPW Diplexer." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/14345795455975207965.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>89<br>Compared to traditional planar transmission lines such as microstrip, and coplanar waveguide, the microshield line allows single modes, TEM wave propagation with low dielectric loss, low radiation loss, and almost zero dispersion with air dielectric. In this dissertation, the design of microwave diplexer is based on microshield line and accomplished by silicon micromachining technology. To begin with, two coplanar waveguide inductive-coupled filters are designed for transmitter and receiver operation in X-band. By combing the two filters with simulate length in feeding sections, the diplexer design is in good agreement with the simulation results and experimental data. Then, a microwave diplexer in terms of gap-coupled bandpass filters in Ka-band is accomplished through a cascadedλ/4 parallel coupled lines sections. The microshield line is chosen as the transmission line, which is formed by etching in <111> direction of ＜100＞silicon wafer and is in a trapezoidal cross sectional shape. For which, the characteristic impedance is calculated by employing an in-house program based on the quasi TEM assumption. The microwave diplexer in Ka-band is fabricated by the micromachining process. The measured and simulated results are compared to verify the design.
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Liu, Da-Wei, and 劉大維. "Substrate integrated waveguide filter and diplexer design." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/36850005544668744323.
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碩士<br>元智大學<br>通訊工程學系<br>95<br>Along with the communication progress, the frequency that product uses is getting higher and higher, and the product requirements become more and more stringent. When the design frequency gradually increases, there are lots of problems to overcome, such as more loss of circuit, difficulties of manufacturing and measuring product. In this paper, beginning by the traditional waveguide theory and design method, application of the substrate integrated waveguide (SIW) techniques, to design substrate integrated waveguide filter and diplexer.
The transition is use to connect SIW and microstrip line. In this paper, use the automated design method to design a new type of transition by exponential taper. From 8.5GHz to 13GHz, the return loss is less than 20dB.
In the part of filter, it divided into iris-coupled filter and dual-mode filer. The iris-coupled filter measured with less than 3dB insertion loss, more than 17dB return loss, and 8.2% 3dB bandwidth. The dual-mode filter measured with less than 3dB insertion loss, more than 13dB return loss, and 13.2% 3dB bandwidth.
Diplexer designed by H-plane straight Y-junction and two dual-mode filters with different passband. The lower band measured with 3dB insertion loss, more than 15dB return loss, and 7.8% 3dB bandwidth. The upper band measured with 5.5dB insertion loss, more than 12dB return loss, and 6.1% 3dB bandwidth. The isolation between port 2 and port 3 is more than 17dB.
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Wei-Chen, Lin, and 林韋辰. "Microstrip / CPW fed Microstrip Filter and Diplexer Designs." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/43923351223685293139.
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碩士<br>國立彰化師範大學<br>電信工程研究所<br>98<br>In this thesis, the study of planar structure filter designs which include the wide stopband band-pass filter, diplexer, and wide bandwidth band-pass filter. Firstly, the filter, possesses the wide stopband performance is presented. Thus, the filters is composed of CPW（coplanar waveguide）and the microstrip line. The insertion loss of pass-band was very good. In the design of diplexer, the mechanism of transmission zeros implantation is employed to improve the isolation between I/O ports.
In the wide stopband band-pass filter design, a band-pass filter (BPF) using forked stepped-impedance resonators (SIRs) was proposed with having a very wide stopband performance. The circuit composed of two forked SIRs connected with a narrow microstrip with the latter’s middle point shorting to the ground through a via hole. The FSIRs filter operated in a quarter-wavelength resonance condition. The filter was built for WLAN IEEE 802.11b/g (2.4/2.45 GHz) applications. A long narrow coupled microstrip which increasing the stopband range was used to couple I/O signal to/from the resonators. The upper stopband, its frequency range was measured from 2.76 to 23.08 GHz with the criterion of the signal rejection levels greater than 20 dB. The stopband’s upper-end is over 9.5 f0 with the central frequency of 2.44 GHz.
In the design of diplexer, we propose a novel design of a UMTS diplexer using a coupled microstrip line in conjunction with the stepped-impedance resonator. The diplexer is composed of two band-pass filters, which termed as the Tx- and Rx-filter. The feature is designed to transmit-band (Tx-band) and receive-band (Rx-band) both implantation in the low and high end of the band limit having adjustable transmission zeros. Transmission zero has been implanted in each filter design for increasing the isolation between the Rx- and Tx-port. In addition, the coupled line with the addition of spur-line can produce an extra transmission zero. The superposition of the extra zero and the original one further enhances the isolation effect. The measured isolations are greater than 30 dB in Tx-band and Rx-band. The measured central frequency is 1.94 GHz in Tx-band. Its 3-dB bandwidth is 100 MHz which encounters the range from 1.88 GHz to 1.98 GHz. Measured transmission zeros are at 1.52 GHz and 2.12 GHz. The Rx-band measured central frequency is 2.12 GHz. The 3-dB bandwidth is 130 MHz which covers the frequency range from 2.06 GHz to 2.19 GHz. The measured transmission zeros are at 1.94 GHz and 2.41 GHz.
In the design of wide bandwidth band-pass filter, an asymmetrically cross-shaped multi-mode resonator fed by the CPW has implemented in the wide bandwidth band-pass filter design. The pass-band exhibits very low insertion loss. The broadside-coupling of the CPW and the resonator provides a strong capacitive coupling which enhances the wide bandwidth performance. The measured 3-dB bandwidth is 2.37 GHz. The pass-band range covers from 2.13 GHz to 4.5 GHz. The measured upper stop-band bandwidth is 2.38 GHz with the criterion of the signal rejection levels greater than 20 dB. Two transmission zeros are implanted on both sides of the pass-band to enhance the signal selectivity.
In this thesis, the designs of the proposed filters should be able to apply to wireless microwave circuit design.
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Chu, Chi-Ping, and 邱繼平. "Filter and Diplexer Design with Microstrip Rectangular Resonators." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/78979086187775958187.
Full textAbstract:
碩士<br>國立臺灣大學<br>電信工程學研究所<br>93<br>In the beginning of this thesis, we design a compact and highly selective narrow-band filter. The highly selective response can be achieved by introducing transmission zeros which may be realized by cross coupling a pair of nonadjacent resonators of the filter.
In addition, we design the diplexer by using the above-mentioned filter designed at 2GHz and 3GHz, respectively. The two filters are connected by the microstrip lines whose lengths have to satisfy appropriate phase condition.
To reduce the diplexer size, stepped impedance resonators are adopted in the diplexer design. Through this way the eight resonators can be reduced to six. This diplexer, however, improves the size but degrades the isolation.
Another way to reduce the diplexer size is that two filters share the same input stepped-impedance resonator. And the diplexer of this type not only has a more compact size but also keeps the very good performance. Thus we have verified that this is practical to combine two filters by using stepped impedance resonators in the diplexer design.
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Ou, Tsung-Hsing, and 歐宗信. "Design of a Ka band HUB diplexer module." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/48455752431137944983.
Full textAbstract:
碩士<br>國立交通大學<br>電機學院碩士在職專班電信組<br>95<br>The thesis is a design of Ka band HUB diplexer module which would be applied to the intelligent transport system to play the role of on-board or road-side unit. It is not only the interface between the microwave (IF signal) and millimeter-wave (RF signal) to up- or down-convert signals, but also allowed to provide full-duplex communication channels for both ELEMENT A and B of operation frequency near 2.4 GHz.
This designed module is included in three sub-modules: IF sub-module, local frequency sub-module and RF sub-module. The function of IF sub-module is converting the operation frequency of ELEMENT A up to 3.4 GHz, and combining itself with the signal of ELEMENT B as the IF signal. There are one voltage controlled oscillator and a phase-locked loop circuitry in the local frequency sub-module to stably give not only IF sub-module a local frequency source of 5.85 GHz, but also additional two sets of 17.55 GHz source for the transmitting and receiving RF sub-module respectively by circuitries of frequency tripler, power divider and amplifiers. The RF sub-module is applying the inner sub-harmonic mixer to converting the IF signal up to RF pass-band and then transmitting it via the antenna, or to converting the received RF signal down to IF pass band for the IF sub-module.
The final measured result: the communication distance between the on-board and road-side unit is 10 meter at the data rate of 950K bytes per second.
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Lin, You-Yu, and 林佑諭. "Study on the Design Method of Planar Diplexer." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/57757861216541002634.
Full textAbstract:
碩士<br>華梵大學<br>電子工程學系碩士班<br>94<br>This thesis is devoted to the design method of planar diplexer. Two equivalent circuit of diplexer are proposed; they are named as equivalent circuit I and equivalent circuit II hereafter. The synthesis methods of these two equivalent circuits have also been developed successfully. The second part of this thesis is developing the design method of planar diplexer based on the equivalent circuit using the sequential open-circuit tuning method. This design method enables the responses of the designed diplexer close to those of the equivalent circuit.
The equivalent circuit I comprises two lump-element filters connecting in parallel. The parameters of this circuit can be optimally calculated from the synthesis program to satisfy the specifications of diplexer. Ideal response can be achieved for the equivalent circuit after synthesis procedure. The equivalent circuit II comprises two lump-element filters connected through distributed T-junction. Before the design of this second equivalent circuit, the s-parameters of the T-junction have to be obtained from simulation. The synthesis program combines these s-parameters and the two lump-element filters to optimally find the parameters of equivalent circuit II satisfying the specifications of diplexer. The equivalent circuit II also has ideal responses after synthesis.
This thesis employs the equivalent circuit II to design the planar diplexer because of its similarity to real diplexer. The two filters of diplexer can be designed on simulation software based on the equivalent circuit parameters, like the coupling coefficients, using the sequential open-circuit tuning method. The two filters can be easily designed by this method. The planar diplexer is then fromed by connecting the T-junction to the two designed filters. In order to make the responses of diplexer closer to those of equivalent circuit, computer optimization technique is employed to find adjust the diplexer. The diplexer after sequential tuning procedure serves as good initial guess. The planar diplexer can be optimally designed by the optimization function of simulation software.
This research has employed the synthesis program of equivalent circuit I to design several diplexers with different channel spacing. Several contiguous band diplexers, with different lengths of feed lines, are also designed by the synthesis program of equivalent circuit II. There planar contiguous band diplexers are designed and fabricated in this research. They are :1) microstrip diplexer with mini-hairpin resonators, 2) stripline diplexer with mini-hairpin resonators and 3) microstrip diplexer with step impedance resonators. The validity of the proposed design method is confirmed by the measurement results.
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Yu, Szu-Hsien, and 余思嫻. "The Low Temperature Cofired Ceramic Balanced Diplexer Module." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/71536247656493753737.
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碩士<br>國立交通大學<br>電信工程系所<br>93<br>This thesis presents a small-size and low-insertion-loss balanced diplexer module by using LTCC technique. This module comprises two diplexers, five bandpass filters, a lowpass filter, and two baluns. The circuit components will use LTCC material with high dielectric permittivity (33) and low dielectric loss. The diplexer module will meet IEEE 802.11a(5.2GHz、5.7GHz) and 802.11b(2.4GHz) wireless LAN’s specifications. In order to save space, LTCC balance diplexer module will be integrated with surface-mounted MMIC switch. The lowpass filter is designed based on the theory of the m-derived filter. The bandpass filter is a three-pole combline filter with cross-coupled capacitances. The diplexer is composed of two transmission lines, a lowpass filter, and a bandpass filter. Last, we connect the bandpass filter and baluns together to complete the designs.
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Cheng, Yen Hung, and 鄭嵓鴻. "Designs of Tunable Multi-band Filter and Diplexer." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/15992517157845660805.
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Wang, Chien-Hsiung, and 王建雄. "2.4/5.2-GHz Stepped-Impedance Diplexer With Spurious Suppression." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/65878991373688552907.
Full textAbstract:
碩士<br>國立臺灣海洋大學<br>電機工程學系<br>95<br>The diplexer using stepped-impedance resonators can control its spurious frequency. Moreover, the defected ground structures not only can suppress the spurious and improve the performance of the diplexer, but also can further reduce the size of the circuit. In this thesis, the stepped-impedance resonators and the defected ground structures are used to design the 2.4/5.2-GHz stepped-impedance diplexers with spurious suppression.
In this thesis, the theory of the design of diplexer using stepped-impedance resonators is analyzed firstly. Next, the influence of the defected ground structures on the spurious suppression and the frequency response of the microstrip lines are studied. Finally, the basic and miniaturized diplexers are designed and realized, respectively. In addition, the characteristics of these diplexers are measured.
From the analyzed results, it is noted that both two diplexers designed by the stepped-impedance resonators have good performance. On the other hand, the diplexer designed with defected ground structure not only can reduce the size of the circuit about 20.5%, but also can suppress the spurious below -20dB to improve the performance.
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Chang, Po-Ying, and 張博奕. "Research of Microstrip Coupled-Line Bandpass Filter and Diplexer." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/43258530698022243721.
Full textAbstract:
碩士<br>國立中央大學<br>電機工程研究所<br>95<br>In this study, several kinds of microstrip coupled-line structures are used to implement compact bandpass filters, which are based on quarter-wavelength resonators. Compared to the conventional parallel-coupled bandpass filters that are based on half-wavelength resonators, the circuit size of proposed filters are reduced by more than half. The passband of proposed coupled-line filter can be made switchable by a proper circuit layout along with the incorporation of diodes to change the resonance characteristics of quarter-wavelength resonators. An on-off isolation of more than 20dB up to 3 has been achieved. In addition, by utilizing the inherent transmission zeros of coupled-lines, the 30dB stopband bandwidth of proposed filter can be extended up to 4 . Moreover, by manipulating the phase of input reflection coefficient, we can implement diplexers based on proposed filter structures with smaller circuit size than conventional designs. Additional cross-coupling between non-adjacent coupled-line sections can also be introduced to improve the selectivity.
In this work, the characteristics of different kinds of coupled-line sections are thoroughly investigated to make the best use of them in bandpass filter and diplexer designs. Simple and clear design flows have also been proposed for all designs, which allow the easy extension of proposed filter structures for further improvement in the future.
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CHEN, GUAN-LIN, and 陳冠霖. "Design and implementation of the balanced RF diplexer circuit." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/w5x79q.
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碩士<br>華梵大學<br>電子工程學系碩士班<br>105<br>The purpose of this paper is to use the four-layers FR4 printed circuit board (PCB) designed to be used in the Wi-Fi frequency band of the balanced RF diplexer circuit and combined with RF switch to make up the RF front-end module(FEM). First, two balanced filters are designed to operate at 2.5 GHz and 5.5 GHz respectively, and then through the matching circuit will be composed of two circuits RF balanced diplexer. The balanced filter consists of three parallel-coupled microstrip lines and parallel capacitors, the matching circuit is a T-type structure consisting of a series capacitor and a parallel inductor. In the balance RF diplexer output port connected to the RF SPDT Tx/Rx switch composed of RF front-end module(FEM).The size of the balanced RF diplexer is 30 mm x 30 mm x 0.64 mm, the size of the RF front-end module is 52 mm x 42 mm x 0.64 mm.
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Liu, Yi-Ting, and 劉伊婷. "Study of Ultra-Wideband Ring Bandpass Filters and Diplexer." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/95864983068017828816.
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碩士<br>國立高雄應用科技大學<br>光電與通訊研究所<br>96<br>This thesis presents a simple method to design a high performance ring wideband bandpass filter centered at 4 GHz without the perturbation element is presented. The coupling between the two orthogonal modes is accomplished by combing the resonant mode of the ring resonator and the resonant mode of the coupling line having a length about λg/4 with respect to 4 GHz. This fabricated filter at center frequency f0 of 4 GHz has showed very good measured characteristics, including a 3-dB fractional bandwidth of 40 %, a very low insertion loss of 0.3±0.1 dB, a stopband from 6-10 GHz and a very high selectivity.
The thesis also presents a compact and low loss ring ultra-wideband (UWB) bandpass filter (BPF) with an enlarged perturbation element is designed and implemented on FR4 substrate. This filter at center frequency f0 of 4.16 GHz has presented almost very good measured characteristics including the bandwidth of 3.04-5.27 GHz (3-dB fractional bandwidth of 54%), a low insertion loss of 0.8 dB, a high passband selectivity due to two transmission zeros in the passband edges, and a low group delay varied between 0.1 and 0.6 ns. Experimental results of the fabricated filter show a good agreement with the predict results.
Furthermore, a high performance dual-mode diplexer for the direct sequence ultra-wideband communication is designed and implemented. This microstrip diplexer is mainly composed of two dual-mode wideband bandpass filters and two tapped open stubs. The design concept is proposed in detail and has been verified by the experimental results. The fabricated diplexer has the excellent performances including the two isolated wideband bandwidths of 3.01–5.3 GHz and 6.4–10.25 GHz, low insertion loss and high isolation of 20dB. Experimental results also show a good agreement with the simulated results.
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Chi, Chao-Nung, and 紀兆濃. "Design and Fabrication of V-band Microwave CPW Diplexer." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/70653264672272531728.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>90<br>In terms of gap-coupled and edge-coupled lines,two filters with center frequency equal to 63GHz and 56GHz are designed for the transmitting and receiving bands, respectively. With the advantages of low loss, low dispersion,and low radiation, the MEMS(Micro-Electro-Mechanical System) was used to fabricate the filters. The measured center frequency of the filter was slightly lower than the simulation one.The measured insertion loss in the passband was smaller than the simulation results ranging from 6 to 8dB,better than that of 11 dB if implemented by the traditional planar circuit filter.Then,the two filters are combined to form a diplexer and fabricated with MEMS technique.The measured insertion loss is 6dB in the transmitting band of 63 GHz and 7dB in the receiving band of 56GHz.The microshield line is chosen as the transmission line in this study and the characteristic impedance is calculated by employing an in-house program based on the quasi TEM assumption.
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Lin, Chun-Sheng, and 林俊升. "Design of 2.45 GHz Active Circulator and Passive Diplexer." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/mx974p.
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碩士<br>國立臺北科技大學<br>電腦與通訊研究所<br>94<br>This thesis is to extract increase the isolation of active circulators. First, to introduce the theory of active circulators include quasi circulators, and produce them
by active and passive circuits. The insertion loss of active circulators is to expect minimum. To observe the isolation of active circulators, find out the reasons the
isolation is low and its bandwidth is too narrow and modify the characteristic by many experiments. Passive circuits are made by microstrip lines, and active circuits
are consists of SGA-8343. The unbalanced amplitude of two signals used phase cancellation could be expected By VB programs. After VB programs computed, the attenuation of the two signals is known. Then, using multiple active or quasi circulators the new architecture increase the isolation will be found out. By comparing the isolation of single and multiple architecture, the feasibility of multiple architecture in MMIC technology will be expect.
In the other hand, bandpass and bandstop filters will be design by microstrip lines, and its insertion loss is about 3dB. A diplexer will be consisted of different type filters. By the design procedures of active circulator and diplexer, the isolation of different transmitting and receiving modes, using single frequency and dual frequencies, will be discussed.
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Hsu, Shih-Hsuan, and 徐士軒. "Design and manufacture of RF diplexer using composite filter configuration." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/62093316850260810528.
Full textAbstract:
碩士<br>國立臺灣科技大學<br>電子工程系<br>105<br>In the thesis, we propose the diplexer by using two different bands composite filter configuration with a T-junction microstrip line and fabricated with 4-layered FR4 manufacture. In this study, we use Keysigkt’s ADS to do the circuit and the electromagnetic simulation, and The MathWorks’s MATLAB for the theory formula verification.
In chapter 2, we deal with the composite low-pass filter, the composite low-pass filter consists of the low-pass constant-k filter section and the low-pass m-derived filter section. The transmission zero will provide by low-pass m-derived filter section, the transmission zero frequency could be control by parameter m to achieve band selectivity.
In chapter 3, we will introduce the composite band-pass filter. First, we modify the high-pass filter T-section to band-pass filter T-section by adding two capacitors. One is on the parallel arm and series by the inductor, another is shunt by the inductor. There are two benefits from the capacitors, the series one provides a transmission zero at low frequency from pass-band and reduce interferences from low-frequency side-band; the shunt one provides the broad band band-pass frequency response. This two capacitors aC and bC are the key parameter to the band-pass filter T-section, we will analysis it with image parameter method and verification by MATLAB. We produce a parameter design chart for the parameter a and parameter b. after complete the band-pass filter T-section design, we connect band-pass filter T-section to two low-pass constant-k section for the attenuation requirement, the illustration by the response between attenuation factor and frequency.
Finally, we connect the proposed composite low-pass filter and composite band- pass filter and the T-junction together to implement the diplexer in chapter 4 and illustrate the measure result. Conclusion in chapter 5.
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Kun-Hung, Tsai. "Differential bandpass filters and differential diplexer for WLAN using LTCC." 2005. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2607200514174600.
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Huang, Hung-Shuo, and 黃宏碩. "Active diplexer implemented by using LTCC process and discrete transistors." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/91005842692585013828.
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碩士<br>國立臺灣大學<br>電子工程學研究所<br>99<br>This thesis realized an active diplexer using composite left/right-handed transmission line. By controlling the phase shift between gate line and drain line, we can have cancellation in forward output port and amplification in backward output port at lower frequency and the opposite characteristic at higher frequency. Because its characteristic is similar to passive diplexer in the front-end of a transceiver system, it is called an active diplexer.
We find the possible solutions based on mathematical analysis. By controlling the phase of transmission lines at gate and drain, we can control the frequency of maximum gain at forward and backward direction. We implement passive elements in LTCC process and using HJFET transistors NE3512S02 from NEC. The active diplexer is designed to work at 2.4GHz and 5.2GHz
Keyword: distributed amplifier, diplexer, composite left/right-handed transmission line.
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Tsai, Kun-Hung, and 蔡昆宏. "Differential bandpass filters and differential diplexer for WLAN using LTCC." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/46168805072030293285.
Full textAbstract:
碩士<br>國立臺灣大學<br>電子工程學研究所<br>93<br>In the paper, we present a new balanced filter and a balanced diplexer for dual-band wireless local-area network (WLAN). By using the balanced-type circuit, balun can be eliminated. The balanced circuit can also improve the poor ground and suppress the common-mode interference. In addition, this filter which uses two finite transmission zeros can improve the filter rolloff rate near passband and the diplexer which uses LC resonator can obtain better isolation.
The LTCC (low temperature co-fired ceramic) is chosen for our component implementation for its low loss and multi-layer structure, which will give better insertion loss and give more freedom in balanced-type device design.