This thesis proposes a new bandpass filter prototype modified based on T-type coupled resonator architecture by considering the parasitic shunt capacitance effect. After derivation, the new prototype can be proved equivalent to third-order Chebyshev bandpass filter. It is easy to realize the new prototype circuit by utilizing the inductor and capacitor library established from electromagnetic simulations. The couplings between circuit components can cause some transmission zeros to enhance attenuation rate at stopbands. This thesis designs several bandpass filters embedded in 4-layer laminate package substrate with center frequency at 2.45GHz. The measurement results show that most of these filters can achieve less than 1.7dB insertion loss and more than 14dB return loss at passband, and more than 30dB attenuation at 950MHz, 4.8GHz and 7.2GHz. One of the filters has a size of 1.9¡Ñ2.7mm2, which is the smallest area for the currently reported bandpass filters embedded in the organic package substrate.

This thesis is mainly divided into two parts. The first part discusses in detail design flow of the coupled-resonator bandpass filters, including basic theory of synthesis and the procedure of electromagnetic (EM) simulation. In the second part, by using the above-mentioned design flow, different structure filters have been implemented on organic substrates. The coupled-resonator BPF designs are verified to overcome the elements¡¦ parasitic effects, and thus can be optimized with high degree of freedom. In practice, a 3rd-order bandpass filter by coupling three spiral resonators has been proposed and implemented, having miniature and wide stopband characteristics. Finally, a two-layer 4th-order cross-couple bandpass filter with a pair of transmission zeros has been also proposed and implemented, achieving a significant size reduction of 50% compared with the single-layer design. The simulation and measurement results have good agreement for all design cases in this thesis.

A second-generation CMOS current controlled conveyor (CCCII) and a tunable IF bandpass filter based on the CCCII are developed. The high frequency property and the control ability of the current conveyor makes the bandpass filter tunable in the range between 55MHz~410MHz, which is suitable for the IF filter application that is around 200MHz~300MHz. The Q-factor is also tunable and has a maximum value up to 800.

A novel CMOS tunable bandpass filter and a novel voltage controlled oscillator are proposed. Both circuits are designed using the UMC 0.5£gm CMOS process parameters. The CMOS tunablebandpass filter is realised by using the intrinic parasitic capacitance of the MOS transistor. This filter has neither on-chip planar inductor nor poly-capacitance; therefore, the chip area is reduced. Simulation results show that the bandpass filter is tunable in the range between 190MHz and 347MHz. Therefore, the filter is suitable for the IF filter application that is between 200MHz and 300MHz. The Q-factor is also tunable and has a maximum value of 983. Applying the circuit of the bandpass filter, a second order voltage controlled oscillator is designed. Simulation results show that the voltage controllable oscillator is tunable in the range between 444MHz and 746MHz.

In this thesis, we propose a miniaturized LTCC balanced filter that integrates bandpass filter (BPF) and balun. In order to reject interferences, we have the transmission zero of out-band by extra capacities and inductances in the prototype of Second-Order BPF. On the other hand, we miniaturize the balun by revising the length of couple-line with four shunt capacities. The practice size of the miniaturized balanced filter is 2.0mm x 1.25mm x 0.95mm.The insertion and return losses are less than -2.5dB and -20dB over operating frequency band, respectively. The phase difference is less than 5 ¢X, and the amplitude difference is within -0.5dB in operating frequency band. The size is the smallest in the similar commercial product and relative journal.

Wireless systems with emerging applications are leaning towards small size, light-weight and low cost. Another trend for these wireless devices is that new applications and functionalities are being added without increasing the size of the device. To accomplish this, individual components must be miniaturized and the system should be designed to maximize the integration of the individual components. The high level of 3D integration feasible in system on package design (SoP) concept can fulfill the latter requirement. Bandpass filters are important components on all wireless systems to reject the unwanted signals and reduce interference. Being mostly implemented with passive and distributed components, bandpass filters take considerable space in a wireless system. Moreover, with emerging bands and multiple applications encompassed in a single device, many bandpass filters are required. The miniaturization related to bandpass filters can be approached by three main ways: (1) at the component level through the miniaturization of individual bandpass filters, (2) at the system level through the use of tunable filters to reduce the overall number of filters, and (3) at the system level through the high level of integration in a 3D SoP platform. In this work we have focused on all three aspects of miniaturization of band pass filters mentioned above. In the first part of this work, a low frequency (1.5 GHz global positioning system (GPS) band) filter implemented through 3D lumped components in two leading SoP technologies, namely low temperature co-fired ceramic (LTCC) and the liquid crystal polymers (LCP) is demonstrated. The miniaturized filter is based on a second order topology, which has been modified to improve the selectivity and out-of-band rejection without increasing the size. Moreover, for the case of LCP, the filter is realized in an ultra-thin stack up comprising four metallization layers with an overall thickness of only 100 _m. Due to its ultra-thin structure, the LCP filter is ten times smaller size as compared to the filters reported in published work. The filter is exible and, therefore, suitable for conformal applications. In the second part of this work, relatively higher frequency (Ku band) distributed bandpass filter is presented which can be tuned through an applied magnetic field. This has been realized in a relatively new LTCC tape with magnetic properties, known as ferrite LTCC. Traditionally, magnetically tunable filters require large external electromagnets or coils, which are non-integrable to typical planar circuit boards and are also inefficient. To demonstrate high level of integration, completely embedded windings realized in multiple layers of LTCC have been used instead of the external coils. As a result, the presented bandpass filter is several orders of magnitude smaller that the reported ones. Aside from reducing the size, the embedded windings based design is more efficient than the external coils because it can avoid the demagnetization effect (fields lost at air-ferrite interface) and thus require much smaller bias fields for tunability. Though the embedded windings bring in a number of advantages as mentioned above, the currents passing through these windings generate considerable heat which can inuence the performance of the microwave structure (bandpass filters in our case). This has never been studied before fro Ferrite LTCC based designs with embedded windings. In this work, the effect of the heat generated by these windings has been investigated. It has been found that this self-heating effect inuences the tunability of the filters considerably so it must be estimated at the design stage. Therefore, a strategy to simulate this effect has been developed. The resultant simulations agree well with the measurements verifying the simulation strategy. The designs presented in this work demonstrate the feasibility of realizing highly integrated, miniaturized and tunable filters in SoP platform which are very suitable for modern and futuristic small form factor and slim wireless devices.

No description available.

This dissertation mainly discuses various microstrip bandpass filter (BPF) designs. The filter designs include: a coupled line BPF using nonuniform arbitrary image impedances, miniaturized BPF utilizing dumbbell shaped slot resonator (DSSR), BPF employing isosceles triangle shaped patch resonator (ITSPR), BPF with a complimentary split ring resonator (CSRR) and triple-band BPF (TBBPF). In the coupled line BPF designs, a capacitive gap-coupled BPF and parallel coupled line BPF are introduced, where two different arbitrary image impedances are applied for the designs. Based on the proposed equivalent circuit model, the coupled BPF's design equations are derived, and they are validated from comparisons of the calculated and simulated results. For a miniaturized BPF, the DSSR is utilized in the filter design. An equivalent circuit model of the DSSR is also presented and validated through simulations and measurements. The ITSPR is introduced for simple BPF and diplexer designs. The ITSPR's design equations, effective dielectric constant, and fractional bandwidth are discussed, and their validities are demonstrated from electromagnetic (EM) simulations and measurements. The coupled type complementary split ring resonator (CSRR) is introduced for a compact direct-coupled BPF. The proposed unit cell of the resonator consists of two CSRRs, where gaps of outside rings face each other to achieve a strong cross coupling. For an analysis of the coupled CSRR, an equivalent circuit model is discussed and validated through circuit and EM simulations. Based on the coupled CSRR structure, two-/four- pole direct-coupled BPFs are designed, simulated, and measured. The TBBPF design using admittance inverters are presented. In the TBBPF design, the center frequencies and fractional bandwidths (FBW) of each passband can be adjustable. Low cost phased array systems operating from 8 to 12 GHz are introduced. A phased array using a piezoelectric transducer (PET) phase shifter is designed and tested. Compared to the phased array using the PET phase shifter, another phased array utilizing 4-bit monolithic microwave integrated circuit (MMIC) phase shifters is demonstrated. Both phased array systems are simple and easy to fabricate.

As the microwave wireless communication systems growing rapidly, microstrip planar ceramic filters attract many attentions because of the advantages of small size, low cost, easy fabrication, higher performance and easy integration. In this thesis, several kinds of bandpass filters are designed for different operating purposes. First, two kinds of dual-mode bandpass filters are designed for 2.4 GHz wideband with the T-shaped I/O arranging in a straight way for easy integration. Second, the hook-coupling and insert-coupling structures are adopted for series connecting of the stepped-impedance resonator structures, and 2.4/5.2 GHz dual-band filtering properties could be achieved. Third, two open-loop rectangular ring resonators and U-shaped I/O are designed for 2.4/5.2 GHz dual-band bandpass filters with deep transmission zeros. The quarter wavelength stubs and groove structures are used for enhancing deep transmission zeros between two passband and ripples of the second passband, respectively. Fourth, the parallel positioned resonators with phase difference method are used to design the dual-band (1.23/2.4 GHz) and quad-band (1.23/2.4/3.5/5.2 GHz) bandpass filter with asymmetrical bandwidths and transmission zeros. In the thesis, high quality Al2O3 ceramic substrates are used to fabricate different kinds of bandpass filters for pattern minimization and low losses. The electromagnetic simulators, HFSS and IE3D, were used to adjust and optimize the associated parameters. The printing method was used to fabricate the proposed bandpass filters, which did not need using the FeCl3 to etch the Cu plate from the surface of Duroid or the FR4 substrates. The proposed filters are measured by Agilent-N5230A with the SMA connectors welding. Finally, the simulated and measured results of proposed bandpass filters are in good agreement.

Today's microwave circuits, whether for communication, radar, or testing systems, need compact tunable microwave filters. Since different microwave circuit applications have radically different size, power, insertion loss, rejection, vibration, and thermal requirements, new filter technologies with different balances between these requirements are always desirable. Negative Refractive Index (NRI) transmission media was discovered 10 years ago with the unique property of negative phase propagation. A literature review was conducted to identify potential NRI methods for filters and other devices, but no NRI tunable filters were found. To address this gap, a family of tunable NRI bandpass filters was simulated and constructed successfully using end-coupled zeroth order resonators. Tuning was accomplished by controlling the negative phase length of the NRI sections with varactors. The resulting L-band filters exhibited a 25-40 percent tunable range, no higher order resonances, and required only one fourth the length of a coupled-line filter constructed from traditional 180 degree microstrip resonators.