The suspended stripline resonator is arranged on a dielectric substrate suspended inside a metal case (Fig. 1) . It has four strip conductors. The longest conductor with open-circuited ends is placed on the upper side of the substrate. It is folded in the form of a hairpin. There are spacings between its edges and metal sidewalls. All other conductors are placed on the lower side of the substrate. Two of them are disposed opposite the open ends of the upper conductor. One of their ends is closed to the sidewall of the metal case. The third lower conductor is disposed opposite the middle of the upper conductor. It makes this resonator different from all known resonators. One of its ends is closed to the opposite sidewall. The second resonant frequency can be lowered considerably compared with the first resonant frequency because the middle lower conductor has capacitive coupling with the upper conductor in its voltage antinode segment. That is a precondition for functioning of a dual-mode filter.
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Abstract—This paper presents a direct synthesis approach for UWB BPFs. The modiﬁed Chebyshev ﬁltering function is used to characterize the frequency response over the whole frequency range of the BPF. As for the ﬁlter’s circuit, open circuited MMR capacitively coupled with I/O ports is used, and two shunt short-circuited stubs are placed at the two ends of the connecting line to sharpen the rejecting skirt of the passband. The equivalent circuit’s transfer function is derived. By equating the ﬁltering function to the transfer function of the circuit, the design parameters are obtained. The uniform connecting line is then replaced by nonuniform line to suppress spurious harmonics and achieve very wide stopband. In order to avoid critical precision requirement in the fabrication of the ﬁlter, we design the ﬁlter using suspended stripline (SSL) technology to replace the parallel-coupled microstrip lines (PCML) with very small coupling gaps. Finally, a ﬁlter prototype is designed and fabricated to experimentally validate the presented method. Experimental results show good agreement with EM-simulated and theoretical ones.
Abstract—A quasi-lumped design of a suspended stripline (SSL) bandpass ﬁlter (BPF) exhibiting high signal selectivity is proposed. In the circuit, transmission zeros were implanted to enhance the stopband signal rejection. A sample BPF having an operation band of 6.77– 7.33 GHz was fabricated and measured for performance veriﬁcation of the proposed design.
Abstract—We propose a novel UWB bandpass filter (BPF) design using the suspended stripline (SSL). The filter composes of a low-pass and a high-pass circuit, both implemented by SSL structures. A notch response structure might be implemented to the filter by embedding a resonant slotline. The quasi-lumped elements circuit models were developed to analyze these circuits’ performance. Experiments were conducted, and good agreements were observed between the measurements and simulations.
Abstract—In this paper, a high power, air suspended stripline (SSL) T junction power divider at L band microwave frequencies is introduced. The power divider operating frequency is centered at 1.3 GHz. In this new configuration, the only dielectric used is air to have maximum power handling capability. An excitation transition from coaxial cable to the SSL transmission line is explained. The SSL was fabricated using aluminum sheets to gain the advantage of low cost. The power divider design was validated using circuit and 3D full wave simulations and confirmed using experimental measurements with all agreements. It has been proved that the power divider attenuation has sharp rejection characteristic at the designed frequency (−20 dB at 1.3 GHz). The power divider can be used as a feeder for devices used in high power applications.
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The characteristics of periodic broadside-coupled suspended stripline with the diﬀerent periodic patterns are similar to the characteristic of the corresponding periodic structure in single conductor suspended stripline with symmetrically located substrate, in which the structure has a lower cut-oﬀ frequency, f c , narrow passband,
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mode application, 2.39 mm × 1.2 mm is chosen for the size of housing. The model in Fig. 3 is optimized in HFSS, and the simulated results are shown in Fig. 5. The rejection is more than 23 dBc from DC ∼ 20 GHz for IF, and the maxim insertion loss is 0.2 dB for LO in 40 ∼ 60 GHz range. Two U-band waveguide to suspended stripline transitions are added for S-parameter measurement in waveguide interface scalar network analyzer. The model for simulation and its photograph are shown in Fig. 6. In the frequency range of LO, 40 ∼ 60 GHz range, the measured insertion loss of LO signal is lower than 0.5 dB. Measurements show good agreement with simulated data as in Fig. 7. This IF block can also be used in other applications, like multipliers, switches or wideband filters.
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As shown in , a six-port device is composed of three 3-dB couplers and in-phase or out-of-phase power divider. In this paper, the design of a wideband six-port network that features a fully integrated device on the planar microstrip is proposed. In order to improve the bandwidth and directivity factor, 8.34-dB quadrature directional couplers by series connection are adopted. A multilayer circuit structure consists of three conductor layers interleaved by two dielectric layers. A suspended stripline Wilkinson power divider on medial layer connects directional couplers by a via hole. In order to integrate the power divider and directional couplers, transitions are employed by suspended striplines. Many microwave devices such as directional coupler , power Combiner , ﬁlter [11, 12] were designed using suspended striplines which with low dissipation, temperature performance, as well as good batch consistency, is very suitable for broadband microwave components design.
The constructed wetland (CW) in the settlement of Gložan is the first system of its kind for wastewater treatment constructed in Vojvodina (Serbia), aimed at treating local municipal wastewater. The common reed Phragmites australis, naturally growing at the CW location, was used as biofiltering vegetation. The monitoring effectiveness of the CW was based on removing suspended solids and reducing the amount of organic matter. The eight-year long study shows that the age of the constructed wetland does not significantly affect the changes (increase) in concentration of suspended particles and organic compounds from the wastewater effluent. We proved that measured values of variables, suspended solids, and biochemical oxygen demand (BOD 5 ) of effluent belong to the same population. The chronological data series of suspended solids and BOD5 of effluent were processed using statistical tests of homogeneity, both parametric (Student’s t-test with Fisher’s F-test) and nonparametric (Mann-Whitney’s U-test). The results of testing homogeneity of the data confirm that the constructed wetland has not been compromised, and that the removal of suspended solids is 93–96% and reduction of organic com- pounds, expressed in terms of BOD 5 , is up to 79–84%.
direction occurs . The efficiency of the antenna with two different bias line lengths showed similar trends, rapidly increasing from a few percent to more than 80% in the 0–1 THz frequency range and achieving saturation (with an average value of approximately 94%) in a wide frequency range from 1 THz to 6 THz. It is obvious that the efficiency at low frequencies was immune to the rippling caused by resonant behavior when a sufficiently long bias line was used. These investigations indicate the necessity of using long bias lines in the design of typical H-shaped coplanar stripline antennas if one is to achieve good radiation performance, particularly in the low operating frequency region of less than 1.0 THz.
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In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control application, are presented using the method of moments (MoM) in two dimensions. This technique is adapted to study the complex configuration of the line’s system, which does not have a simple analytical solution. The modeling of this structure consists in analyzing the primary inductive and capacitive matrices ([L] and [C]). When these matrices are determined, it is possible to cal- culate the inductive and capacitive coupling coefficients (k L and k C ) and estimate the resulting scattering parameters of
This article presents a computer-assisted approach to the study of character discourse in Dickens. It focuses on the concept of the ‘suspended quotation’ – the interruption of a character’s speech by at least five words of narrator text. After an outline of the concept of the suspended quotation as introduced by Lambert (1981), the article compares manually derived counts for suspensions in Dickens with automatically generated figures. This comparison shows how corpus methods can help to increase the scale at which the phenomenon is studied. It highlights that quantitative information for selected sections of a novel does not necessarily represent the patterns that are found across the whole text. The article also includes a qualitative analysis of suspensions. With the help of the new tool CLiC, it investigates interruptions of the speech of Mrs Sparsit in Hard Times and illustrates how suspensions can be useful places for the presentation of character information. CLiC is further used to find patterns of the word pause that provide insights into how suspensions contribute to the representation of pauses in character speech.
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In this thesis, we analysed the suspended users in Twitter and studied several ap- proaches to predict whether a user will be suspended or not. First, we took a review of the some related works. Benevenuto et al.  and Moh et al.  gave a good work on classification of spammers with high accuracy. However the works from them meet a problem that the size of dataset is too small. They only focus on a narrow subdo- main of twitter, which means their work cannot directly be scaled to the whole twitter social network. Moreover, the feature set they selected can be easily manipulated by spammers to act like a real user so that their approach cannot detect them.
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Appeal], so yes, the public’s opinion is relevant, but it’s only one of the factors’. Another judge was not influenced ‘in a particular case’ but suggested that ‘if there is a sufficient uproar over a period of time concerning the level of sentencing for some particular crime, I am sure it affects the severity of sentences’. This was echoed by a third judge, who admitted to having been influenced by the impact a suspended sentence may have on public opinion, as well as having become more punitive in response to public attitudes, adding however that he still did not give offenders as much as the public or victim wants, since ‘that’s not the task [the public] set me. You didn’t set me to be the front row of the lynch mob.’ 56
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Modeled performance is shown in Fig.14 simulated insertion loss and return loss result of 3 rd order edge- coupled stripline band pass filter EM analysis results from Ansoft Designer, which indicates that the response satisfies the design criteria along with shown in Fig.15 simulated result by MATLAB simulated tool. Reflection regarding in accuracies present the between the two simulators results and simulation results show that the filter operation is optimum over the frequency range 38 GHz to 40 GHz which is best in this range. The simulated insertion loss is less than 0.5 dB in pass band. Also the response is flat and uniform over the entire pass-band. In addition, reflection coefficient is 0.00001 which is nearly equal to 0 and a perfect match exists.The filter is almost matched to the characteristic impedance (Zo), 50 Ohms. Also it is observed that the phase varies linearly with frequency.
Abstract—Vertical transition structure between grounded coplanar waveguide (GCPW) and stripline by Low Temperature Co-ﬁred Ceramic (LTCC) technology is presented in this paper. In this structure, the top ground of the stripline is used as the GCPW lower ground, while the signal via goes through the middle ground plane. With increasing vertical signal via height, it can be more widely used in the higher height of multilayer System in Package (SiP) module packaging. The circular openings in the ground plane and additional shield vias around the transmission lines can provide great advantage in the radiation loss and decrease parasitic eﬀects. The measurement results show that the return loss is less than − 10 dB from 6 GHz to 35 GHz. Meanwhile, the insertion loss is better than − 2 dB up to 28.4 GHz.
The use of different radiating structures for radiated susceptibility test Electromagnetic Compatibility (EMC)is a field of ongoing research. Especially with relative long wave lengths for frequencies between 2-30 MHz in the confined space of an anechoic chamber which is used to test for radiated susceptibility it is not easy to generate a strong and uniform electric field for large pieces of equipment. The main question in this research was to see whether it was possible to build a large stripline antenna for the testing of pieces of equipment of roughly 2.0m high, combined with a high field strength of 200 V/m when using a 2.5kW amplifier.
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The suspended.substrate stripline technology offers various attractive advantages, which are comparable to a microstrip or other planar transmission lines. Filtering circuits implemented using suspended.stripline structures achieve high signal selectivity, lower insertion loss and good temperature stability. This is because the suspended.stripline technology uses the air as the dielectric material to connect to the ground plane, thus minimising the signal transmission losses associated with dielectric material loss. Another key advantage of the suspended.stripline structure is that the circuit patterns can be printed on both sides of the stripline substrate, which enables strong broadside electromagnetic (EM) coupling, as well as the use of a metal housing that prevents the EM fields of the filter from radiating loss. Because suspended stripline is a purely transverse electromagnetic (TEM) transmission.line structure, it is non. dispersive, and thus makes the suspended stripline an interesting structure for high.performance filters. Presently, only a dual.mode suspended.substrate stripline was demonstrated using quarter.wave resonator and inductor . However, it was designed for broadband frequency and the insertion loss and return loss obtained were worse than 1 dB and 10 dB in the passband frequencies, respectively.
A suspended substrate two-conductor resonator and a ﬁlter on its base were proposed in 2004 , and some details are described in [7, 8]. Such a resonator consists of a dielectric substrate suspended in metallic case; two strip conductors are placed on the substrate’s faces: one on the upper face and the other on the bottom face. Each conductor is grounded by its one end at the opposite walls of the case. The resonator possesses a number of notable properties  that allow designing ﬁlters to have better performance than the microstrip ones. First, it has higher Q 0 -factor, which grows when substrate
Abstract—In this work, CPW-to-stripline (SL) vertical via transi- tions using gradually stepped vias and embedded air cavities are pre- sented for V-band LTCC System-on-Package (SoP) applications. In order to reduce radiation loss due to abrupt via discontinuities, grad- ual via transitions are proposed and investigated. In addition, in order to reduce increased parasitic shunt capacitance due to stepped via structures, air cavities are embedded below the transition vias. Us- ing a 3-D EM simulation tool, the proposed transitions are designed and analyzed, compared to the conventional transition. Three-segment transmission lines (CPW-SL-CPW) in 7-layer LTCC dielectrics were fabricated and measured. The two stepped via (STV2) transition em- bedding air cavities shows an insertion and return losses of 1.6 dB and below − 10 dB, respectively, over 60 GHz. The transition loss per one STV2 transition is 0.7 dB at 60 GHz.