Yuxia Mo

Wideband Four-Way Out-of-Phase Slotline Power Dividers

Two new wideband four-way out-of-phase slotline power dividers are proposed in this paper. The half-wavelength slotlines are employed to construct the presented compact power dividers. Based on the proposed power-dividing circuit, a four-way power divider is implemented with compact size and simple structure. To obtain high isolation among the four output ports and good output impedance matching, another four-way out-of-phase slotline power divider with improved isolation performance is designed by introducing an air-bridge resistor and two slotlines with isolation resistors. The simulated and measured results of the proposed power dividers demonstrate reasonable performance of impedance matching, insertion loss, amplitude balancing, and isolation among the output ports.

Miniaturized Triple-Band Bandpass Filter Using Coupled Lines and Grounded Stepped Impedance Resonators

A triple-band bandpass filter with good selectivity based on modified grounded stepped impedance resonators (SIRs) is presented. The fundamental and first higher order resonances of the two λ/4 grounded SIRs are utilized to obtain dual-band response. Moreover, bandwidths of the two passbands can be controlled by tuning the distance between the two grounded vias. Owing to the use of two λ/2 fork resonators, another passband can be realized without increasing additional feedlines, which can be designed independently while other passbands are not affected. Several transmission zeros (TZs) are generated on each side of the passbands to obtain good selectivity. The λ/4 SIRs are embedded inside of the λ/2 fork resonators to realize miniaturization. The measurement and simulation results show good agreement.

Wideband Four-Way Filtering-Response Power Divider With Improved Output Isolation Based on Coupled Lines

A planar 4-way power divider with bandpass filtering response based on the coupled line is presented. Its frequency response is similar to a coupled line filter. Moreover, open stubs are utilized to get good frequency selectivity by introducing transmission zeros and improve input match. Three isolation resistors are used to satisfy both transmission and isolation property. The equivalent even- and odd-mode circuits of the power divider are analyzed, while the design equations are derived. Comparison of the measured and simulated results is presented to verify the theoretical predications.

Bandpass Filter with Wide Stopband Using Composite Right/Left Handed Transmission Line

Abstract This paper presents a wide-stopband bandpass filter (BPF) based on mixed coupling of the composite right/left handed transmission line (CRLH-TL). First the CRLH-TL resonator is introduced and analyzed. Then mixed coupling (Both electric coupling path and magnetic coupling path exist) of the novel resonator is explained. Based on the structural features of the CRLH-TL resonators, this coupling path can generate an additional transmission zero near passband without increasing the overall size of the filter. Then, good selectivity of the proposed BPF can be obtained. Meanwhile, in order to get a wide stopband, two open stubs are employed to suppress harmonic response of the CRLH-TL resonator. The filter is developed and analyzed based on microwave network theory and equivalent circuit method. The proposed BPF has been designed, fabricated, and measured. The measured results agree with the predicted ones closely.

Compact Dual-Passband Filter Using Spiral Resonators

A novel compact dual-band bandpass filter using spiral resonators and input/output (source-load) direct coupling structure has been presented. Two different transmission paths are utilized to realize independently controllable central frequencies and bandwidths for each passband. In addition, three transmission zeros has been introduced to improve the frequency selectivity. A dual-passband filter centered at 2.41 GHz and 4.22 GHz is designed, simulated, and fabricated to demonstrate the performance of the proposed filter structure. The measured results show good agreement with the simulated ones.

Wideband out-of-phase SIW power divider with enhanced stopband

A wideband multi-way out-of-phase substrate integrated waveguide (SIW) power divider with improved rejection band by using novel hybrid multiple-via probe and multiple radial slots has been presented in this letter. The novel hybrid multiple-via probe and multiple radial slots are employed to achieve wideband and improved rejection band respectively. An eight-way out-of-phase SIW power divider is designed, fabricated, and measured. Good agreement between simulated and measured results is obtained in the desirable frequency range. The measured average insertion loss of the eight-way power divider is approximately 9.3 dB and return loss is greater than 15 dB from 3.5 GHz to 8 GHz, as well as an rejection band with more than 25 dB attenuation from 9 GHz to 11.2 GHz. A maximum amplitude imbalance of ±0.3 dB and phase imbalance of ±3° are observed over the entire operating frequency range.