Showing papers on "Stopband published in 2009"
TL;DR: In this paper, a substrate integrated waveguide with square complementary split-ring resonators (CSRRs) etched on the waveguide surface is investigated, which allows the implementation of a forward-wave passband propagating below the characteristic cutoff frequency of waveguide.
Abstract: A substrate integrated waveguide with square complementary split-ring resonators (CSRRs) etched on the waveguide surface is investigated in this paper. The proposed structures allow the implementation of a forward-wave passband propagating below the characteristic cutoff frequency of the waveguide. By changing the orientations of the CSRRs, which are incorporated in the waveguide surface and can be interpreted in terms of electric dipoles, varied passband characteristics are observed. A detailed explanation for the generation and variations of the passbands has been illuminated. The application of this waveguide and CSRR combination technique to the design of miniaturized waveguide bandpass filters characterized by transmission zeros is then illustrated. Filter design methodology is examined. These proposed filters exhibit high selectivity and compact size due to the employment of the subwavelength resonators and an evanescent-wave transmission. By slightly altering the configuration of the CSRRs, we find that the propagation of the TE10 mode can be suppressed and filters with improved selectivity and stopband rejection can be obtained. To verify the presented concept, three different types of filters are fabricated based on the standard printed circuit board process. The measured results are in good agreement with the simulation.
340 citations
TL;DR: In this article, the wave attenuation and energy transfer mechanisms of a metamaterial having a negative effective mass density were studied from an energy transfer point of view, and it was found that most of the work done by the external force on the lattice system is stored by the internal mass if the forcing frequency is close to the local resonance frequency.
Abstract: The wave attenuation and energy transfer mechanisms of a metamaterial having a negative effective mass density are studied. The metamaterial considered is represented by a lattice system consisting of mass-in-mass units. The attenuation of wave amplitude for frequencies in the stop band is studied from the energy transfer point of view. It is found that most of the work done by the external force on the lattice system is stored by the internal mass if the forcing frequency is close to the local resonance frequency. However, the energy stored in the internal mass is only temporary; it is taken out by the external force in the form of negative work in a cyclic manner. This behavior is utilized to design metamaterials for preventing stress waves from passing them.
322 citations
TL;DR: In this article, a novel technique for the elimination of the open stopband in one-dimensional periodic printed leaky-wave antennas is presented, where a quarter-wave transformer, or alternatively a matching stub, is introduced into the unit cell of the antenna, which forces the Bloch-wave impedance of the structure to remain real and non-zero at broadside.
Abstract: A novel technique for the elimination of the open stopband in one-dimensional periodic printed leaky-wave antennas is presented. A quarter-wave transformer, or alternatively a matching stub, is introduced into the unit cell of the antenna, which forces the Bloch-wave impedance of the structure to remain real and non-zero at broadside. The effectiveness of the proposed technique is first demonstrated on a printed periodic microstrip leaky-wave antenna consisting of a single radiating stub per unit cell, which exhibits a significant stopband at broadside. The technique is then also applied to a structure consisting of two radiating stubs per unit cell, which is capable of mitigating, but not eliminating, the open stopband. In both cases the open stopband at broadside is completely suppressed.
237 citations
TL;DR: In this paper, a wideband and compact filter design for common-mode noise suppression in high-speed differential signals is proposed based on two U-shaped and one H-shaped coupled patterned ground structure.
Abstract: A wideband and compact filter design for common-mode noise suppression in high-speed differential signals is proposed based on two U-shaped and one H-shaped coupled patterned ground structure. An equivalent model of three coupled LC resonators to predict the common-mode suppression characteristics is also developed with good agreement to the full-wave simulation and measurement result. A test sample is designed and fabricated on a standard printed circuit board (PCB). It is found the common-mode noise can be reduced by the filter over 15 dB from 3.6 to 9.1 GHz and over 75% of amplitude in the time domain. More important, the differential signal integrity, in terms of insertion loss and group delay in the frequency domain and eye diagrams in the time domain, is not degraded within the wide bandwidth. The fractional bandwidth of the stopband can reach 87% and the filter size is about 0.44 lambdag times 0.44 lambdag. The radiation caused by the common-mode current on the attached I/O cables is also efficiently suppressed by 10 dB on average within the designed stopband. To our best knowledge, it is the first low-cost common-mode filter designed for the gigahertz high-speed signals with the largest fractional bandwidth and most compact size on a PCB.
218 citations
TL;DR: In this article, a differential-mode wideband bandpass filter (BPF) on microstrip line is proposed with good common-mode suppression, and the predicted and measured performances are in good agreement with each other.
Abstract: A differential-mode wideband bandpass filter (BPF) on microstrip line is proposed with good common-mode suppression. A four port two stage branch-line differential-mode BPF is first designed. Then, open circuited stubs are attached to the middle of two of the vertical branches. As such, its two-port bisection becomes a bandpass or bandstop filtering topology under differental- or common-mode excitations, respectively. The lengths and widths of these stubs can be properly adjusted to produce a highly attenuated and widened stopband under the common-mode operation. Finally, a wideband differential-mode BPF is designed and fabricated. The predicted and measured performances are in good agreement with each other, showing good common-mode suppression with an insertion loss higher than 20 dB over the differential-mode passband with a fractional bandwidth of 65%.
185 citations
TL;DR: In this article, patent pending substrate integrated waveguide (SIW) bandpass filters with moderate fractional bandwidth and improved stopband performance are proposed and demonstrated for a Ka-band satellite ground terminal.
Abstract: In this paper, patent pending substrate integrated waveguide (SIW) bandpass filters with moderate fractional bandwidth and improved stopband performance are proposed and demonstrated for a Ka-band satellite ground terminal. Nonphysical cross-coupling provided by higher order modes in the oversized SIW cavities is used to generate the finite transmission zeros far away from the passband for improved stopband performance. Different input/output topologies of the filter are discussed for wide stopband applications. Design considerations including the design approach, filter configuration, and tolerance analysis are addressed. Two fourth-order filters with a passband of 19.2-21.2 GHz are fabricated on a single-layer Rogers RT/Duroid 6002 substrate using linear arrays of metallized via-holes by a standard printed circuit board process. Measured results of the two filters agree very well with simulated results, showing the in-band insertion loss is 0.9 dB or better, and the stopband attenuation in the frequency band of 29.5-30 GHz is better than 50 dB. Measurements over a temperature range of -20degC to +40degC show the passband remains almost unchanged.
148 citations
TL;DR: In this article, two different slot resonators are embedded into the arc shaped ground plane of the circular disk patch antennas in order to obtain the desired band-rejection around 5.8 GHz.
Abstract: Planar ultrawideband (UWB) antennas with on-ground band-notched structures are studied in this paper. Two different slot resonators, which feature quarter-wavelength and half-wavelength configurations, are embedded into the arc shaped ground plane of the circular disk patch antennas in order to obtain the desired band-rejection around 5.8 GHz. Their principles and characteristics are analyzed and compared in detail providing designers with in-depth understanding and useful design information. By choosing the quarter-wavelength slot resonator, the first spurious stopband can be pushed up to 3 f 0 (f 0 stands for the center frequency of the notch) and this antenna retains a super wide working band which spans from 1.62 GHz to 17.43 GHz. Performance in both the frequency domain and time domain for this antenna has been investigated carefully. The transmission response of a transceiving antenna system and their corresponding transient analysis are discussed at the end of this paper.
134 citations
TL;DR: In this paper, a tri-band bandpass filter with independently controllable center frequencies and improved stopband rejection characteristic is presented, and two kinds of filter configurations with cascaded and pseudo-interdigital formats are proposed.
Abstract: A novel approach for designing tri-band bandpass filters with independently controllable center frequencies and improved stopband rejection characteristic is presented in this paper. The assembled resonator constructed by a stepped impedance resonator and a common half-wavelength resonator is employed to obtain tri-band response. The stepped impedance resonator is designed to operate at the first and third passbands and the other resonator is designed to operate at the second passband. Two kinds of filter configurations with cascaded and pseudointerdigital formats are proposed. Based on lossless lumped-element equivalent circuit, it is found that both filter structures can introduce transmission zeros between passbands. To verify the proposed approach, two filters are designed and fabricated, the measured results exhibit tri-band bandpass responses with high selectivity.
132 citations
TL;DR: In this paper, a novel ultra-wideband (UWB) bandpass filter with compact size and improved upper-stopband performance has been studied and implemented using multiple-mode resonator (MMR).
Abstract: In this letter, a novel ultra-wideband (UWB) bandpass filter with compact size and improved upper-stopband performance has been studied and implemented using multiple-mode resonator (MMR). The MMR is formed by attaching three pairs of circular impedance-stepped stubs in shunt to a high impedance microstrip line. By simply adjusting the radius of the circles of the stubs, the resonant modes of the MMR can be roughly allocated within the 3.1-10.6 GHz UWB band while suppressing the spurious harmonics in the upper-stopband. In order to enhance the coupling degree, two interdigital coupled-lines are used in the input and output sides. Thus, a predicted UWB passband is realized. Meanwhile, the insertion loss is higher than 30.0 dB in the upper-stopband from 12.1 to 27.8 GHz. Finally, the filter is successfully designed and fabricated. The EM-simulated and the measured results are presented in this work where excellent agreement between them is obtained.
108 citations
TL;DR: In this article, a step-impedance resonator with different dimensions is used to design bandpass filters with a dual-passband response, as well as good rejection levels in the extended upper stopband.
Abstract: Stepped-impedance resonators with different dimensions are used to design bandpass filters with a dual-passband response, as well as good rejection levels in the extended upper stopband. To achieve the goal, the resonators are designed to have two identical leading resonant frequencies, but dispersed higher order ones to make spurious peaks have low levels and small bandwidths. The stopband is then extended and the rejection levels are enhanced by collocating transmission zeros with the unwanted peaks. The zeros are tuned by adjusting the coupling lengths of the coupled stages and sliding the tap positions of the dual-band transformers along the end resonators. Measured results of two experimental circuits show a rejection level of 30 dB up to more than eight times the first passband frequency can be obtained. The measured data have good agreement with the simulation.
103 citations
TL;DR: In this paper, a compact microstrip dual-mode resonator and filter was proposed to achieve a 60% reduction in the size of the two-dimensional resonators and filters.
Abstract: A novel compact microstrip dual-mode resonator and filter are proposed. The characteristics of the dual mode resonator are investigated. It is found that the filter response exhibits a desirable stopband response where the first spurious passband naturally occurs at 3f0. Finally, methods of miniaturizing such resonators and filters are discussed. The proposed structure was able to achieve 60% size reduction.
TL;DR: In this article, a dual-mode ring resonator is constituted to allocate its first two resonant frequencies in the UWB band, and the dual-line parallel-coupled structure is used in this compact UWB filter, which is expected to achieve much tighter coupling degree.
Abstract: This letter presents a novel compact ultra-wideband (UWB) microstrip bandpass filter with spurious response suppression. A dual-mode ring resonator is constituted to allocate its first two resonant frequencies in the UWB band, and the dual-line parallel-coupled structure is used in this compact UWB filter, which is expected to achieve much tighter coupling degree. Simulated and measured results are found in good agreement with each other, showing a wide passband from 4.9 to 10.9 GHz, 15 dB return loss bandwidth of about 5 GHz, minimum insertion loss of 0.49 dB at 7.3 GHz, and wide upper stopband with more than 20 dB attenuation up to 20 GHz.
TL;DR: In this paper, a Y-shaped dual-mode microstrip bandpass filter with input-output cross-coupling is presented, where the resonance frequencies of the degenerate modes can be adjusted easily to satisfy the bandwidth of the BPF.
Abstract: A Y-shaped dual-mode microstrip bandpass filter (BPF) with input-output cross-coupling is presented. The characteristic of the Y-shaped dual-mode resonator has been investigated. The resonance frequencies of the degenerate modes can be adjusted easily to satisfy the bandwidth of the BPF. A parallel-coupling feed structure with a cross coupling has been used to generate two transmission zeros at the lower and upper stopband, which can improve the out-of-band performance. A broadband dual-mode microstrip BPF has been designed, fabricated, and measured. The simulated and measured results are in agreement generally. Within the 3.1 to 5.4 GHz bandwidth, the measured insertion loss, return loss and group delay variation are below 0.5 dB, above 15 dB, and below 0.2 ns, respectively.
TL;DR: In this article, a novel microstrip filter using three-mode stepped impedance resonator (TSIR) is presented, with its coupling scheme given so as to accurately predict its desired performance.
Abstract: A novel microstrip filter using three-mode stepped impedance resonator (TSIR) is presented, with its coupling scheme given so as to accurately predict its desired performance. A T-type open stub is introduced into the design of a miniaturized TSIR. It is shown that the developed filter exhibits quasi-elliptic characteristics with sharp skirt and wide stopband. Good agreements are obtained between its measured and simulated S-parameters.
TL;DR: In this paper, an open stub has two functions in the filter: (1) perturbation for the multimode operation and (2) zero point generation at the stopband for the control.
Abstract: A novel multimode bandpass filter with high and wide rejection band is proposed by using an open stub. The open-stub has two functions in the filter: (1) perturbation for the multimode operation and (2) zero point generation at the stopband for the stopband control. With proper input/output coupling, additional two poles, i.e., four poles, can be generated for the proposed filter structure. The design is then verified by experiment. The single structure four-mode filter has low insertion loss, good stopband performance, and compact size and linear phase.
TL;DR: In this article, a novel ultra wideband (UWB) bandpass filter with double notch-bands is presented, where Stepped impedance resonators (SIRs) and broadside coupling technique are used to achieve tight couplings for a wide passband.
Abstract: A novel ultra wideband (UWB) bandpass filter with double notch-bands is presented in this paper. Multilayer schematic is adopted to achieve compact size. Stepped impedance resonators (SIRs), which can also suppress harmonic response, are designed on top and second layers, respectively, and broadside coupling technique is used to achieve tight couplings for a wide passband. Folded SIRs that can provide desired notch-bands are designed on the third layer and coupled underneath the second layer SIRs. The designed prototype is fabricated using multilayer liquid crystal polymer (LCP) technology. Good agreement between simulated and measured response is observed. The fabricated filter has dual notch-bands with center frequencies of 6.4/8.0 GHz with 3 dB bandwidths of 9.5%/13.4% and high rejection levels up to 26.4 dB and 43.7 dB at 6.4/8.0 GHz are observed, respectively. It also has low-insertion losses and flat group delay in passbands, and excellent stopband rejection level higher than 30.0 dB from 11.4 GHz to 18.0 GHz.
TL;DR: In this paper, a dual-band bandpass filter (BPF) is designed to achieve the characteristic of low insertion loss and high isolation for global position system (GPS)/wireless local area network (WLAN) applications.
Abstract: In this letter, a novel compact dual-band bandpass filter (BPF) is designed to achieve the characteristic of low insertion loss and high isolation for global position system (GPS)/wireless local area network (WLAN) applications. This BPF is implemented by properly selecting the impedance ratio (R) and physical length ratio (alpha) of the asymmetric stepped-impedance resonator (SIR) with one step discontinuity. The coupling coefficient between the coupled asymmetric SIRs is calculated by using full-wave simulator IE3D. The proposed filter has very good measured characteristics including a low insertion loss of 1.1 dB for both passbands, a high isolation insertion loss of 55 dB between the two passbands and a wide stopband rejection of 38 dB from 2.7 to 5.3 GHz. Good agreement with responses of electromagnetic (EM) simulation and measurement is compared.
TL;DR: In this article, a microstrip low-pass filter is proposed, which consists of a simple tapered structure using periodical compact microstrip resonant cells, and the proposed lowpass filter has successfully addressed simultaneously the problems of compactness, matching, selectivity, insertion loss and the suppression of spurious frequency bands.
Abstract: A novel microstrip lowpass filter is proposed. It consists of a simple tapered structure using periodical compact microstrip resonant cells. Owing to the introduction of the tapered structure, the proposed lowpass filter has successfully addressed simultaneously the problems of compactness, matching, selectivity, insertion loss and the suppression of spurious frequency bands. A demonstration filter has been designed, fabricated and tested to show the validity of the proposed structure.
TL;DR: In this article, a dual-band bandpass filter is presented, which is composed of generalized negative-refractive-index transmission lines realized in microstrip, and the filtering mechanism relies on all four of the generalized NRI-TLs' left-handed and right-handed passbands.
Abstract: A dual-band bandpass filter is presented. The filter is composed of generalized negative-refractive-index transmission-lines (NRI-TL) realized in microstrip. The filtering mechanism relies on all four of the generalized NRI-TLs' left-handed and right-handed passbands. Under the closed stopband condition, two passbands are achieved. A complete design procedure is described. A fabricated example measures 0.25lambdao0.25lambdao, where omegao is the wavelength of the center frequency of the stopband. Maximum insertion loss in the passbands (centered around 4 GHz) is measured at 1.5 dB.
07 Jun 2009
TL;DR: In this article, a frequency-agile bandstop filter with tunable stopband attenuation and constant absolute bandwidth is described, which is demonstrated by a six-resonator planar microstrip filter with simultaneous varactor-diode tuning of attenuation from 30dB to 50dB and operating frequency from 1.8 GHz to 2.2 GHz.
Abstract: A frequency-agile bandstop filter technology with tunable stopband attenuation and constant absolute bandwidth is described. The technology is demonstrated by a six-resonator planar microstrip filter with simultaneous varactor-diode tuning of stopband attenuation from 30dB to 50dB and of operating frequency from 1.8 GHz to 2.2 GHz, with a stopband bandwidth of 60 MHz and absolute 3dB bandwidth of less than 390 MHz.
TL;DR: In this article, a methodology for the design of miniature lumped element components embedded in a low-temperature co-fired ceramic (LTCC) package is presented, from initial schematic design, through individual element design, to complete device optimization.
Abstract: We present a novel methodology for the design of miniature lumped element components embedded in a low-temperature co-fired ceramic (LTCC) package. The entire process, from initial schematic design, through individual element design, to complete device optimization is discussed. The design and fabrication of novel miniature lumped element LTCC filters is used to validate the proposed methodology. Commercial software tools are used to accurately model and simulate all aspects of the devices to ensure design success. In addition, the filters occupy only 0.03 lambda times 0.05 lambda times 0.004 lambda of a conventional low-permittivity LTCC substrate, which is among the smallest sizes reported. An advantage of these filters is that they use a true third-order topology with three multilayer L-C resonators, leading to superior stopband performance. For the first time, measured results are shown for two new bandpass filters targeted for global positioning system applications. Measured results are in good agreement with the simulations and show an insertion loss of 2.8 dB and a return loss of 21.3 dB at the center frequency of 1.64 GHz.
TL;DR: In this article, a dual-band bandstop filter (DBBSF) with a dualmode loop resonator is presented, which exhibits high skirt selectivity and a wide rejection bandwidth.
Abstract: A dual-band bandstop filter (DBBSF) with a dual-mode loop resonator is presented. In order to allow the DBBSF to exhibit high skirt selectivity and to generate a wide rejection bandwidth a capacitive coupled-line section is introduced. By properly controlling the length of the coupled-line section and the cross-coupled capacitor, more than two finite transmission zeros were inserted at the stopband and enhanced the rejection bandwidth.
TL;DR: In this article, a compact filter for ultra wideband (UWB) applications is proposed and developed through quasi-equal allocation of the first three resonant frequencies of a stub-loaded resonator together with strong input/output excitation.
Abstract: A compact filter for ultra-wideband (UWB) applications is proposed and developed through quasi-equal allocation of the first three resonant frequencies of a stub-loaded resonator together with strong input/output excitation. Measured results show low insertion loss and flat group delay in the entire passband as well as a wide stopband. The size for this single-layer UWB filter without feeding lines is only 9.5×5 mm (0.53 λg ×0.28 λg in which λg is the guided wavelength of 50 Ω microstrip at the centre frequency).
TL;DR: Based on the ground surface perturbation concept, a novel stopband-enhanced electromagnetic-bandgap (EBG) structure has been proposed to suppress the power/ground noise on a three-layer package as discussed by the authors.
Abstract: Based on the ground surface perturbation concept, a novel stopband-enhanced electromagnetic-bandgap (EBG) structure has been proposed to suppress the power/ground noise on a three-layer package. This structure consists of a coplanar periodic pattern on the top layer, a ground plane on the third layer, and a ground surface perturbation lattice on the second layer with eight vias connecting to the ground plane. By designing the dimension and via numbers, the ground surface perturbation lattice can significantly enhance the stopband bandwidth. A generic 1-D circuit model is proposed for the three-layer EBG structure. The reason why the proposed structure can possess wider stopband will be explained. Several test samples are fabricated. The agreement of the stopband between the circuit model and measured results are good.
TL;DR: In this article, a modified optimum bandstop filter (BSF) design is presented, which achieves broad stopband and sharp rejection characteristics by realizing three transmission zeros near the passband edges.
Abstract: In this letter, a modified optimum bandstop filter (BSF) design is presented. Broad stopband and sharp rejection characteristics are achieved by realizing three transmission zeros near the passband edges. Stopband rejection depth and bandwidth can be controlled by the impedances of the configuration. A lossless transmission line model analysis is used to derive design equations. Further, a compact geometry is chosen by replacing the low impedance section with its equivalent dual-high impedance lines, which facilitates convenient folding. To validate the theoretical prediction, a single unit sharp-rejecting prototype BSF having a 20 dB rejection bandwidth of 126% at 1.5 GHz has been fabricated.
TL;DR: In this article, split-ring resonators (SRRs) implemented using ferroelectric materials to modify their resonance frequency by means of a tuning voltage are presented for the first time.
Abstract: Split-ring resonators (SRRs) implemented using ferroelectric materials to modify their resonance frequency by means of a tuning voltage are presented for the first time. SRRs have been used to load a microstrip transmission line on a multilayered substrate including a thick film of barium-strontium-titanate (BST) to obtain a tunable stopband response. The characteristics of the BST layer allow the application of 140 V as tuning voltage to obtain frequency tunability values of around 12.5 . The applied technology is suitable for the fabrication of cost-effective and reliable planar microwave devices.
TL;DR: In this article, a complementary split ring resonators (CSRR) is applied to realize a compact Ultra-Wide Band (UWB) bandpass fllter based on half-mode substrate integrated waveguide (HMSIW) in order to achieve sharpened rejection skirts and widened upper stopband.
Abstract: A novel complementary split ring resonators (CSRR) is applied to realize a compact Ultra-Wide Band (UWB) bandpass fllter based on half-mode substrate integrated waveguide (HMSIW) in this paper. Sharpened rejection skirts and widened upper stopband are achieved due to the two resonant frequencies of the proposed CSRR. Very good agreement is observed between measurement and simulation results.
TL;DR: In this article, the scattering parameters and Johnson noise emission of low-pass stripline filters employing a magnetically loaded silicone dielectric down to 25 mK were reported.
Abstract: We report on the scattering parameters and Johnson noise emission of low-pass stripline filters employing a magnetically loaded silicone dielectric down to 25 mK The transmission characteristic of a device with $f_{-3dB}$=13 GHz remains essentially unchanged upon cooling Another device with $f_{-3dB}$=04 GHz, measured in its stopband, exhibits a steady state noise power emission consistent with a temperature difference of a few mK relative to a well-anchored cryogenic microwave attenuator at temperatures down to 25 mK, thus presenting a matched thermal load
TL;DR: In this paper, the scattering parameters and Johnson noise emission of low-pass stripline filters employing a magnetically loaded silicone dielectric down to 25 mK were investigated.
Abstract: We report on the scattering parameters and Johnson noise emission of low-pass stripline filters employing a magnetically loaded silicone dielectric down to 25 mK. The transmission characteristic of a device with f-3dB=1.3 GHz remains essentially unchanged upon cooling. Another device with f-edB=0.4 GHz, measured in its stopband, exhibits a steady state noise power emission consistent with a temperature difference of a few mK relative to a well-anchored cryogenic microwave attenuator at temperatures down to 25 mK, thus presenting a matched thermal load.
TL;DR: Improved performance thin-film plate acoustic wave resonators (FPAR) using the lowest order symmetric Lamb wave (S0) propagating in highly textured AlN membranes are demonstrated and satisfactory agreement with the proposed experimental frequency characteristics of S0 2-port FPARs has been achieved.
Abstract: Improved performance thin-film plate acoustic wave resonators (FPAR) using the lowest order symmetric Lamb wave (S0) propagating in highly textured AlN membranes have been previously demonstrated for the first time. In this work, an experimental study of the resonators' performance vs. a variety of design parameters is performed. Devices operating in the vicinity of the stopband center exhibiting a Q-value of up to 3000 at a frequency of around 875 MHz are demonstrated. Further, low-loss high-Q micromachined 2-port longitudinally coupled thin-film resonators using the S0 mode are demonstrated for the first time. For the analysis of the proposed structures, the coupling-of-modes (COM) approach is successfully employed. Initially, the COM model is used for the extraction of physical parameters from one-port FPAR measurements. Subsequently, using the COM model, a satisfactory agreement with the proposed experimental frequency characteristics of S0 2-port FPARs has been achieved, and possibilities for further improvements in the performance discussed. Finally, the frequency spectrum of the one-port devices has been studied and the excited plate modes at different frequencies identified and presented with their Q-factors and temperature coefficients of frequency (TCF).