Jun Ye Jin

A Novel Compact

This paper presents a novel compact E-plane waveguide filter using multiple resonators, which lead to multiple transmission zeroes. The proposed filter is less than 0.15 λ g in length of a waveguide. The key of the proposed method is to design the locations of transmission zeroes. Four transmission zeroes, of which two are located in the upper stopband, while the other two are in the lower stopband, are produced by four resonators. The couplings between the resonators and locations of the transmission zeroes are carefully analyzed and designed, which enhance the selectivity as well as the out-of-band performance. Theoretical studies and experimental investigations are conducted to demonstrate the proposed design. The good agreement between the simulation results and measurement results is achieved. Moreover, this kind of filter can be implanted well in E-plane structures.

E

This paper presents a novel dual-band bandpass waveguide E-plane filter using three pairs of resonators. In this configuration, two pairs of resonators are on the top of the substrate and the last pair is at the bottom. The length of proposed filter is less than 0.14 λgL or 0.17 λgH(λgL and λgH are standard waveguide wavelengths of the first and second passbands, respectively). Two passbands are designed flexibly with high selectivity and low insertion loss. A sample of the proposed dual-band filter is fabricated and tested. Good agreement between the simulation and measurement results is achieved. This kind of dual-band waveguide filter has benefits of low cost and mass production.

-Plane Waveguide Filter With Multiple Transmission Zeroes

We propose an effective method to alleviate the conflict between large group delay and wide frequency band in electromagnetically induced transparency (EIT) design. Two kinds of electrically induced transparency (E-IT) and magnetically induced transparency (M-IT) are proposed, respectively. Then an EIT with wide transparency window is developed by combining the independent E-IT and M-IT structures. All of the transparencies are designed in a closed waveguide system, and high efficiency is obtained at the same time. One sample is fabricated and the bandwidth is increased to more than 3 times without decrease of the group delay and increase of the size.

A Novel Dual-Band Bandpass E-plane Filter Using Compact Resonators

The transmission characteristics of the parallel strip lines (PSLs) are studied. Then a novel dual-band power divider using PSLs is introduced. It consists of four -form arms and one 180° phase swap structure. The -form arms are capable of achieving ideal impedance matching at two different frequency bands with an arbitrary power dividing ratio The 180° phase swap structure is frequency independent, which is used to obtain high port to port isolation. Theoretical analysis and general design procedure of this power divider with arbitrary and (central frequency ratio of two different frequency bands) are presented. Then, a sample operating at 1.3 and 3.5 GHz with and is fabricated and tested. Experimental results show that this power divider operates at the designed dual frequency bands, and the isolation is more than 20 dB. Good agreements among theoretical, simulated, and experimental results are obtained.

Electromagnetically induced transparencies in a closed waveguide with high efficiency and wide frequency band

The concept of transmission zero resonator pair (TZRP) is used in this paper. Based on this TZRP, a new method to induce a passband is demonstrated, by which different types of bandpass filters can be designed. The proposed TZRP is structured by a pair of resonators with different resonant frequencies, which lead not only to two transmission zeroes, but also to a transmission pole between them. Passband filters can then be built by designing the proximity coupling between the TZRPs, as the TZRP works as a basic resonant element. The passband of these filters can be flexibly controlled by the resonators of TZRPs, which determine the locations of the transmission zeroes and poles. By carefully allocating the transmission zeroes, high selectivity and large out-of-band rejection can be realized. This design method is applied to design filters in two different transmission media, namely, microstrip line and rectangular waveguide. Simulated and measured results demonstrate the effectiveness of this new approach of bandpass filter design. The designed filters have the properties of small size, easy fabrication, low cost, and low loss.

A dual-band power divider using parallel strip line with high isolation

In this paper, a miniaturized evanescent mode waveguide filter using rectangular ring resonators (RRRs) is presented. The evanescent mode waveguide resonator cell (EWRC), composed of a section of evanescent mode waveguide loaded with a pair of RRRs, is designed and analyzed. Quality factors of the EWRC are simulated and calculated. The resonant mechanism and the values of the equivalent lumped elements of EWRCs are given for further design and application of this kind of filter. A miniaturized waveguide filter is designed and fabricated to operate at Ka-band, using the W-band standard waveguide (WR-10) with a cross-sectional size of 2.54 mm × 1.27 mm. The proposed filter can realize a large size reduction compared with the conventional waveguide filter, especially leading to a cross-sectional size reduction of 87.2%. Despite a slight frequency shift, good agreement has been achieved between the simulation and measurement results. The proposed filter has large out-of-band rejection, wide stopband, and high selectivity. In addition, a compact diplexer with high isolation is presented.

Bandpass Filters Designed by Transmission Zero Resonator Pairs With Proximity Coupling

In this paper, a metamaterial-inspired miniaturization method for waveguide filter design is proposed. The transmission response and effective medium parameters of I-shaped resonator in metallic rectangular waveguide are first discussed. By embedding such an I-shaped resonator, a novel λ g/2-type inverter is then proposed (λ g: the guided wavelength). The large effective refraction index with low loss which appears below the resonant frequency of the I-shaped resonator is skillfully exploited, and then the size of λ g/2-type inverter is greatly reduced with acceptable low insertion loss. The most negative permittivity of the I-shaped resonator at its resonant frequency produces an additional transmission zero which leads to sharp skirt selectivity in the upper side band. Using the novel λ g/2-type inverter, two improved waveguide filters are further designed with good performances. One has an extremely compact size. The other has further improved selectivity. Two such filters are finally fabricated and the measured results agree well with the simulated ones.

A Miniaturized Evanescent Mode Waveguide Filter Using RRRs

In this paper, a mixer is designed with low conversion loss through the entire W-band. A novel low pass filter is proposed and used to select the intermediate frequency signal with large rejection of the local oscillator (LO) and radio frequency (RF) signals. A single slot is added on the LO passage to achieve impedance matching in a narrow frequency band, while two slots and one metal strip are added on the RF passage to achieve impedance matching in a wide frequency band. The detailed design process is presented, where a more accurate full-wave simulation model of the adopted diode is suggested. Difference in performances can be obtained by changing the key sizes of the matching structures. One sample is fabricated, and the measured conversion loss is less than 9.5 dB through the entire W-band (from 75 to 110 GHz) under fixed LO condition. The measured return loss of RF port is between 5 and 13.5 dB.

Metamaterial-inspired waveguide filters with compact size and sharp skirt selectivity

We create an invisible gateway simply by putting electric and magnetic superscatterers in a metallic waveguide. The characteristics of the electric and magnetic resonators are analyzed in a metallic hollow waveguide, and the dual-mode superscattering property is discussed in detail to broaden the bandwidth of the invisible gateway. Good agreement is achieved between the simulation and measurement for such an invisible gateway. The present work help readers understand easily how an invisible gateway works (or makes sense) in a classical way without using any complex metamaterial or complicated method of transformation optics.

A wideband mixer designed with low conversion loss through the entire W-band

In this paper, a novel design of an E-plane waveguide filter, called electromagnetically induced transparency (EMIT) filter, is proposed. This EMIT filter is implemented by a rectangular ring (RR) on one side of the substrate and two strip lines resonators (SLRs) on the opposite side, which brings in electrically induced transparency and magnetically induced transparency by the electrical and magnetic couplings between the RR and SLRs, respectively. An equivalent circuit is developed further. Properties of high selectivity, low insertion loss, flat group delay, and small size of only about 0.2λg are realized by this design method. A sample has been fabricated and tested. The measured central frequency is 33.77 GHz with 3-dB fractional bandwidth of 9.4% and the minimum insertion loss in the passband is 0.5 dB. Using the proposed miniature EMIT filter, a diplexer is further designed with compact sizes and low insertion losses. The measured minimum insertion losses are 0.9 and 0.5 dB in the lower and upper passbands centered at 31.79 and 34.74 GHz with 3-dB relative bandwidths of 7.2% and 8.6%, respectively. Good agreements between the simulated and measured results are obtained both in the EMIT filter and the EMIT diplexer.