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A major challenge in the development of highly defined synthetic vaccines is the codelivery of vaccine components (i.e., antigen and adjuvant) to secondary lymphoid tissue to induce optimal immune responses. This problem can be addressed by synthesizing vaccines that comprise peptide antigens covalently attached to glycolipid adjuvants through biologically cleavable linkers. Toward this, a strategy utilizing previously unreported 6"-deoxy-6"-thio analogues of α-GalCer that can undergo chemoselective conjugation with peptide antigens is described. Administration of these conjugate vaccines leads to enhanced priming of antigen specific T cells. This simple vaccine design is broadly applicable to multiple disease indications such as cancer and infectious disease. [ABSTRACT FROM AUTHOR]

Compact planar crossovers with a wide passband are proposed. By cascoding two quarter-wavelength branch-line couplers, a wide passband can be obtained. Moreover, the even-odd mode and the fourfold symmetry are adopted to derive the analytical equations. According to the derived formulas, the transmission lines' impedances Z1, Z2, and ZA, which may influence the performance of the operating fractional bandwidth (FBW), should be properly selected. In terms of experimental verification, the circuit size of the fabricated crossover is 0.23λg × 0.23λg. Moreover, the FBW of the developed crossover is the 59% 1-dB insertion-loss relative bandwidth corresponds to the S31 parameter, whereas the 55% 15-dB one refers to the S21 parameter. In addition, four bandstop filters can be added at four ports of the proposed crossover to achieve a wide stopband performance. [ABSTRACT FROM AUTHOR]

This paper proposes novel multilayered bandpass filters with multiple transmission zeros. These filters are developed with the assistance of semilumped resonators. Moreover, three resonant structures, i.e., open-stub, short-stub, and serial semilumped resonators, used for transmission zeros are provided as well. The fabricated examples are in agreement with theoretical predictions; therefore, our proposed circuits are validated. [ABSTRACT FROM AUTHOR]

A dual-band microstrip bandpass filter is proposed. With the assistance of modified short-circuit quarter-wavelength resonators, the dual-band bandpass filter can be developed. Theoretical analysis and design procedures are provided; the prototypical bandpass filter with dual passbands is fabricated and measured as well. Well-matched simulated results and experimental data validate the proposed filter. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 236–239, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24889 [ABSTRACT FROM AUTHOR]

In this article, a novel microstrip dual-passband bandpass filter has been proposed and developed. This filter is composed of two modified short-circuit quarter-wavelength resonators with a half-wavelength stepped-impedance resonator. Design procedures and theoretical analysis are provided; the prototypical bandpass filter with dual passbands is fabricated and measured as well. Well matched simulated results and experimental data validate the proposed filter. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 3026–3029, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24811 [ABSTRACT FROM AUTHOR]

With the assistance of modified coupled inductors, novel multilayered bandpass filters are developed in this paper. Two or three transmission zeros appear on both sides of the passband skirt easily by incorporating the proposed structures. In order to fabricate compact multilayered bandpass filters, the low-temperature co-fired ceramic technology is also employed. In addition, the equivalent circuits of the modified coupled inductors are also proposed. Consequently, the measured results of the fabricated bandpass filters agree well with the responses of the full-wave electromagnetic design. [ABSTRACT FROM AUTHOR]

The microstrip branch-line coupler with multiple passbands is proposed; moreover, the design equations are provided in this paper. In order to obtain multiple passbands, open stubs are added to the conventional branch-line coupler's ports; in addition, these open stubs' impedance and electrical length need to be properly chosen. The proposed couplers can be easily fabricated on the printed circuit board without any lumped element. The agreement between measured results and the theoretical prediction validates the feasible configuration of the proposed coupler. [ABSTRACT FROM AUTHOR]

A multilayered triplexer is proposed in this article. The ordered of this proposed triplexer can be reduced by inserting a transmission zero, which can also enhance the isolation between two separate passbands. Lowpass and highpass filters, which can make a diplexer due to their complementary characteristics, are utilized to reduce the insertion loss of the proposed triplexer. Moreover, the low-temperature cofired ceramic technology can miniaturize the size of the triplexer. The procedures of circuit design are provided in this article as well. Excellent agreement between measurement and simulation validates the feasibility of the proposed configuration. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2399–2403, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23663 [ABSTRACT FROM AUTHOR]

This paper develops a new multilayered wide-passband bandpass filter with the assistance of low-temperature co-fired ceramic technology. The mutually inductive coupling between the input and output port of a low- and high-pass filter cascaded in the proposed filter is utilized as well. The results show that in the passband of 3.1-4.9 GHz, the measured insertion loss and return loss of this filter are less than 1.1 dB and greater than 18 dB, respectively. In addition, the insertion loss from dc to 2.76 GHz is greater than 20 dB, and the one from 5.8 to 12 GHz is greater than 30 dB. [ABSTRACT FROM AUTHOR]

This paper develops a novel microstrip bandpass filter with ultra-wide stopband. With the assistance of open stubs and interdigital capacitors, a very wide stopband with a sufficient rejection level can be achieved easily. Detailed design and synthesis procedures are provided. Moreover, the electromagnetic simulator IE3D is used, and the prototype of the bandpass filter is fabricated and measured. Good agreement between measured and theoretically predicted results demonstrates feasibility of the proposed filter. [ABSTRACT FROM AUTHOR]

A novel dual-band bandpass filter is proposed in this article. Multiple stepped impedance resonators are shunt-connected with the transmission line section to realize the dual-band filter. Therefore, a transmission zero, which will increase isolation, can be easily generated in the middle of two passbands. Theoretical analysis and design procedures are also described in this article. Moreover, measured results of the fabricated filter match well with the outcome of theoretical prediction, indicating the feasibility of the proposed configuration. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 462–465, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23093 [ABSTRACT FROM AUTHOR]

This paper develops a novel ultra-wideband bandpass filter by cascading a broadband bandpass filter with another broadband bandstop filter. Properly selected impedances of transmission lines achieve broadband bandpass and bandstop filters and make independent designs possible. Detailed design and synthesis procedures are provided; moreover, agreement between measured and theoretically predicted results demonstrates feasibility of the proposed filter. Due to its simple structure, the ultra-wideband bandpass filter newly introduced in this paper is suitable for integration in the single-chipped circuit or implementation on printed circuit boards. [ABSTRACT FROM AUTHOR]

A new method for designing the microstrip branch-line couplers with predetermined compact size and bandwidth is proposed in this paper. With the proposed approach, the size of the quarter-wavelength transmission line in the branch-line coupler can be reduced greatly. In addition,the pn)posed couplers can be easily fabricated on the printed circuit board without any lumped element. A chart concludes the relationship between bandwidth and size reduction rate. It shows that open stubs with low impedance perform better than those with high impedance; moreover, the more open stubs with low impedance utilized, the broader the bandwidth will be. Furthermore, the measured frequency responses show good agreement with the theoretical results. [ABSTRACT FROM AUTHOR]

A novel dual-band bandpass filter with low-temperature co-fired ceramic technology is proposed in this paper. By adopting the structure of an asymmetrical short-circuit coupled line, two open-stub lines, and two reactances, the transmission zeros, which increase the degree of isolation between the passbands, will easily appear at the higher side of two passband's skirts. The analysis of theorem and the procedure of design are described. The measurements of fabricated units match well with the electromagnetic simulation results, which is an evidence of the feasibility of the proposed filter configuration. [ABSTRACT FROM AUTHOR]

A new method for designing the multilayered filter, diplexer, and triplexer is proposed in this paper. The main structure of the multilayered filter is a parallel-coupled line connected with a capacitor. By properly controlling the coupling coefficient between the parallel-coupled line and the capacitor, the transmission zero will appear at the lower or higher passband's skirt. Moreover, such characteristics can be employed to design the diplexer as well for dual- or quad-band portable telephones. In order to miniaturize the size of the circuit and to improve its performance, multilayered structure and the low-temperature co-fired ceramic technology are employed to design and fabricate the filter. Theoretical analysis and design procedures are also provided. Measurement results of fabricated examples are shown to match well with the electromagnetic simulation, which validate the proposed structure. [ABSTRACT FROM AUTHOR]

An effective method to design a low-temperature co-fired ceramic RF bandpass filter with suppression of the harmonic frequency is demonstrated in this paper. The second harmonic, which appears in the frequency band of 4.8-5.0 GHz, is very significant and should be reduced in the 2.4-GHz wireless local area network and Bluetooth application. This feature of harmonic frequency suppression is very important in a communication system to improve linearity, output power, intermodulation performance, etc. The harmonic-suppression filter can be easily obtained by adopting the characteristic of equivalent quarter-wavelength resonators. The detailed three-dimensional layout of each layer is disclosed. By analyzing the influences of the dielectric constant and layer thickness of a ceramic sheet by electromagnetic simulation, the optimal condition for the filter design can be obtained. The measured results agree well with the simulation. Index Terms—Bluetooth; filter; harmonic suppression; low-temperature co-fired ceramic (LTCC); wireless local area network (WLAN). [ABSTRACT FROM AUTHOR]

The out-band transmission zeros of the multilayer low-temperature co-fired ceramic bandpass filter are studied in this paper. The design target of this filter, with the passband between 2.3-2.65 GHz (the true application is 2.4-2.483 GHz), is to reject the local oscillator and image signals and, in the mean time, to suppress the harmonic frequency. This filter is a modified three-pole combline filter, which can easily achieve a high rejection rate and low insertion loss. The source-load coupling capacitor incorporation with cross-coupling grounding inductors can generate three transmission zeros. By properly adjusting the inductance values of the inductors between three resonators and ground can easily manipulate the transmission zero at a high-side skirt to suppress the harmonic frequency. The measured results match well with the electromagnetic simulation that evidences the feasibility of the proposed design. [ABSTRACT FROM AUTHOR]

Examines the chip-type low-temperature co-fired ceramic multilayer ceramic balun using the stepped impedance method. Use of multilayer structure, meander lines and multisection coupled lines on the method; Length of a quarter-wavelength coupled-transmission line; Details on the impedances of balanced output.

In this article, a novel microstrip lowpass filter with complementary split-ring resonators (CSRRs) is presented.By properly controlling the width of the transmission line and rotating the angle of CSRRs, a wide stopband with sufficient rejection level can be achieved. The full-wave electromagnetic simulator IE3D is used; moreover, the prototypical microstrip lowpass filter is fabricated and measured. Simulated results and experimental responses are compared; moreover, the match between simulation and measurement validates the proposed structure. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2592–2594, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25541 [ABSTRACT FROM AUTHOR]

A dual-band voltage-controlled oscillator (VCO) module is proposed by integrating a novel dual-band filter with a dual-band VCO. The resonator designed with the LC-tuned concept in the VCO is capable of switching between two frequency bands. Moreover, the dual-band filter designed with multilayered structure is adopted to achieve harmonic suppression. As a result, the developed VCO module has the capability of harmonic suppression more than 38.61 dB for the measurement upon to two designed frequency bands. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2440–2442, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23647 [ABSTRACT FROM AUTHOR]

The newly method to implement the branch-line couplers has been proposed in this letter. Using the approach of π-model, the size of branch-line coupler can be miniaturized easily. Especially, the proposed coupler without using any lumped element can be easily fabricated on the printed circuit board. In this study, the proposed couplers achieve a physical size reduction of almost 63% with the performance competed with the conventional one. Moreover, the measured frequency responses show good agreement with the theoretical results. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 314–316, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23061 [ABSTRACT FROM AUTHOR]

In this article, a compact cascade quadruplet bandpass filter has been proposed. This bandpass filter has been realized with the semilumped method and can generate a pair of transmission zeros at the two sides of passband by using the nonadjacent cross coupling. The analysis and design procedures are provided in this article. To miniaturize the size of the circuit and improve its performance, multilayered structure and the low-temperature cofired ceramic technology are employed to design and fabricate the filter. Measurement results agree well with the electromagnetic simulation, which can validate the proposed structure. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 3218–3220, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23910 [ABSTRACT FROM AUTHOR]

Ring resonators without central ground plane have been used for determining the effective electrical conductivities of composite conductors. Analytical approximations for the conductor, dielectric, and radiation losses of asymmetric coplanar waveguides are applied in our structures. Good agreement between the theoretical approximations, numerical simulation, and measured quality factors (Q0) of ring resonators realized with several pure conductors is observed. These analytical formulas are used for extracting the electrical conductivity values from measured quality factors of ring resonators realized by Ag composite conductors (silver-amorphous carbon, silver-tin-indium, and silver-tin). [ABSTRACT FROM AUTHOR]