A novel microstrip coupled-line directional coupler is proposed in this paper. It is based on the introduction of a complementary split ring resonator and dumbbell-like defected ground structure on the coupled lines to strongly enhance the designed backward coupling. The designed frequency band is from 1.2 to 1.5GHz. The coupler is fabricated and tested. The insertion loss is less than 3.5 dB. ...

This paper presents a symmetric-type microstrip triple-band bandstop filter incorporating a tri-section meandered-line stepped impedance resonator (SIR). The length of each section of the meandered line is 0.16, 0.15, and 0.83 times the guided wavelength (λ g ), so that the filter features three stop bands at 2.59 GHz, 6.88 GHz, and 10.67 GHz, respectively. Two symmetric SIRs are employed with ...

this paper presents a new design for a microstrip dual-band band-pass microstrip filter (bpf) with suitable isolation between two passbands. in this design, a basic structure is used to achieve a desirable frequency characteristic in the passband. in this regard, defected ground structure (dgs) is implemented to reach optimum parameters of the filter such as bandwidth, return loss, insertion lo...

This paper presents two novel dual-mode dual-band bandpass filters (BPFs) by using stubs loaded coupled line. The analytical equations of their transmission poles and transmission zeros are given by the classical even-/odd-mode method. Design rules for two dual-band BPFs are also given, which show the easily tuned passband frequency locations and in-band performance. As examples, two dualmode d...

Wideband 100 kHz–4 GHz power sensors are presented, which are based on sensing the electrostatic force between an RF signal line and a suspended membrane. The electrostatic force, which is proportional to the square of the rms signal voltage and thus to the signal power, results in a displacement of the suspended membrane. This displacement is detected capacitively, allowing the sensing of the ...

A general design technique for the coaxial resonator cavity duplexer is proposed in this paper, based on the design method of the general Chebyshev band-pass filter. We can obtain the coupling matrixes of cross-coupled resonator duplexer by optimization technique, and complete the design of duplexer fast. The proposed duplexer is designed and fabricated with the 1.92–1.98 GHz downlink and 2.11–...

This paper reports design and development of an innovative compact Stepped Truncated-Circular Waveguide Branching Ortho-Mode Transducer (STCWB-OMT) operating at 4.5–4.8 GHz for horizontal and vertical polarizations. STCWB-OMT is derived by introducing branch waveguide via coupling slot on a stepped truncatedcircular waveguide. This configuration possesses inbuilt rectangularto-circular transiti...

Dual band bandpass filter is designed and optimized for RF wireless applications. The performances of that RF dual band filter are improved especially parameters describing the insertion loss, return losses and rejection. Dual band bandpass filter using stub loaded resonators is designed and characterized. Theoretical results are compared with experimental data. This comparison shows that the m...

This paper presents the design and implementation of a compact 2.4/5.2-GHz rat-race coupler on a glass substrate. Due to the low-loss substrate and thick metal layers, the process provides high-Q capacitors and inductors, and therefore the lumped rat-race coupler is practical. The coupler consists of three bandpass and one bandstop networks to achieve dual-band operations. The measured insertio...