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.

Thesis (PhD)--Stellenbosch University, 2002. / 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. / 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.

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.

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.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2008. / 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.

<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>

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. 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. To the diplexer it was also made a test tool in Labview, through that one gets the magnitude ande phase functions. 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.

The advent of Substrate Integrated Circuit (SIC) technology, and specifically Substrate Integrated Waveguide (SIW) technology has made it feasible to design and fabricate low loss and high quality factor (Q-factor) microwave and millimeter wave structures on a compact and integrable layout and at a low cost. The SIW structure is the planar realization of the conventional rectangular waveguide (RWG). In this technology, the side walls of the waveguide are replaced with two rows of metallic vias, which are connecting two conductor sheets, located at the top and bottom of a dielectric slab. The motivation for this thesis has been to develop an analytical method to efficiently analyze SIW structures, and also design different types of passive microwave components based on this technology. As SIW structures are imitating waveguide structures in a planar format, the field distributions inside these structures are very close to those in waveguides. However, due to the very small substrate height in conventional planar technologies, and also the existence of a row of vias, instead of a solid metallic wall, there is a reduced set of modes in SIW compared to regular waveguide. This fact has given us an opportunity to deploy efficient modal analysis techniques to analyze these structures. In this thesis, we present a Mode Matching Techniques (MMT) approach for the analysis of H-plane SIW structures. One of the areas of application, which can significantly benefit from having an efficient analytical method, is designing and optimizing new circuits. Having such an analytical tool, which is faster than commercially available field solvers by an order of magnitude, new components can be designed, analyzed and optimized in a fast and inexpensive manner. Based on this technique, various types of passive microwave components including filters, diplexers, power dividers and couplers, some of which are among the first to be reported in SIW technology, are designed and analyzed in this thesis. Also based on this technique, the most accurate formula for the effective waveguide width of the SIW is presented in this thesis. In order to provide means to excite and measure SIW components, transitions between these structures and other planar topologies like microstrip and coplanar waveguide (CPW) are needed. More importantly, low-reflection transitions to microstrip are required to integrate SIW circuits with active components, and therefore it is vital to provide low-reflection transitions so that the component design is independent of the influences of the transitions. In this thesis, a new wideband microstrip-to-SIW transition, with the lowest reported reflection coefficient, is also introduced. / Graduate / 0544 / zkordi@ece.uvic.ca

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.

This thesis focuses mostly on investigating different potential applications of meta-transmission line (TL), particularly composite right/left handed (CRLH) TL, and analyzing some new phenomena and applications of meta-TL, mostly left-handed (LH) TL. Realization principle will also be studied.   First, the fundamental electromagnetic properties of propagation in the presence of left-handed material (LHM) are illustrated. The transmission line approach for LHM design is described together with a brief review of the transmission line theory. As a generalized model for LHM TL, CRLH TL provides very unique phase response, such as dual-band operation, bandwidth enhancement, nonlinear dispersion, and the existence of critical frequency with zero phase velocity. Based on these properties, some novel applications of the existing CRLH transmission lines are then given, including a notch filter, a diplexer, a broadband phase shifter, a broadband balun, and a dual band rat-ring coupler. In the design of notch filters and diplexers, CRLH TL shunt stub is utilized to provide high frequency selectivity due to the existence of critical frequency with zero phase velocity. The proposed wideband Wilkinson balun, which comprises of one section of conventional transmission lines and one section of CRLH-TL, is shown to have a 180°±10° bandwidth of 2.12 GHz centered at 1.5 GHz. In the analysis of the dual band rat-ring couplers, a generalized formulation of the requirements about impedances and electrical length of the branches are derived, and as an example, a compact dual-band rat-race coupler is designed utilizing the balanced CRLH TL. Furthermore, a low pass filter is also proposed and designed based on a single (epsilon) negative coplanar waveguide (CPW).Various principles to realize meta-transmission lines are investigated. The main conclusions are listed below:Ÿ         Dual composite right/left handed (D-CRLH) transmission line, which is the dual structure of conventional CRLH TL, shows opposite handedness in the high frequencies and low frequencies with CRLH TL. Meanwhile, in the practical implementation, D-CRLH TL always shows a sharp stopband. A notch filter and a dual-band balun are designed based on D-CRLH TL. Ÿ         The lattice type transmission line (LT-TL) shows the same magnitude response with the conventional right-handed (RH) TL, but a constant phase difference in the phase response over a wide frequency band. A wideband rat-race coupler is proposed as an application of the LT-TL. Ÿ         Finger-shorted interdigital capacitors (FSIDCs) are analyzed and it is shown that FSIDC alone can act as a left-handed transmission line. The value of the reactive elements (inductors and capacitors) in the equivalent circuit model is determined by the dimensions of FSIDC. The relationship between them is analyzed.Later, transmission line loaded with negative-impedance-converted inductors and capacitors is illustrated as the first non-dispersive LH transmission line. The design of a negative series impedance converter is given in detail and a wideband power divider is designed as a potential application of the newly proposed meta-transmission lines in is also given. The final part of the thesis focuses on the study of microstrip lines loaded with complementary split ring resonators (SRRs). An equivalent circuit is made for this structure. The circuit model is verified by the experimental results of cases with different periodic lengths. Thereafter, a meander line split ring resonator (MLSRR) is presented. It shows dual band property and the miniature prototypes of complementary MLSRR loaded transmission lines are fabricated. By comparing the resonance frequencies of complementary MLSRR and multiple SRR, it is shown that the complementary MLSRR is very compact. C-MLSRR is applied in rejecting unnecessary frequencies in the ultra wideband antennas. / QC 20100720