A new microstrip ultra-wideband (UWB) bandpass filter (BPF) with triple-notched bands is presented in this paper. The circuit topology and its corresponding electrical parameters of the initial microstrip UWB BPF are desired by a variation of genetic algorithm (VGA). Then, triple-notched bands inside the UWB passband are implemented by coupling a square ring short stub loaded resonator (SRSSLR)...

Regularly shaped compact microstrip antennas have a small size but their gain is insufficient for most applications. Therefore, a ring-shaped compact microstrip reflectarray with microstrip antenna feed has been proposed. Different configurations, namely, 1 × 3, 3 × 1, plus-shaped and 3 × 3 have been analyzed. The 3 × 3 configuration yields an optimum gain of 10. 8 dBi and a narrow beamwidth of...

A novel approach for the design of a compact multiband monopole antenna for improving radiation characteristics at higher resonant frequencies is presented. The proposed structure consists of a conventional printed monopole loaded with spiral ring resonators and fed by microstrip. When at higher resonant frequency, the electrical length of the conventional monopole antennas is relatively large ...

A miniaturized microstrip rat-race coupler with harmonics suppression is proposed by using shorted trans-directional (TRD) coupled lines. The shorted TRD coupled lines consist of a set of capacitor-loaded λ/4 coupled microstrip lines with two shorts, which are used to replace the 3λ/4 uniform transmission-line section (UTLS) in the traditional 3λ/2 ring coupler for miniaturization. To attain pe...

A wideband differential bandpass filter (BPF) with differential mode passband and common mode suppression is proposed and implemented on microstrip lines for wideband application in this letter. The initial BPF is similar to a single ring resonator with two unequal feed lines which have 180◦ separation and T-shaped stubs are loaded on the ring resonator to form an improved one for better perfor...

Accurate determination of spatial soil moisture distribution and monitoring its temporal variation have a significant impact on the outcomes of hydrologic, ecologic, and climatic models. Development of a successful remote sensing instrument for soil moisture relies on the accurate knowledge of the soil dielectric constant ( soil) to its moisture content. Two existing methods for measurement of ...

A theoretical analysis of a gap-coupled stacked annular ring microstrip antenna with superstrate is performed in order to obtain wider bandwidth operation. The effects of air gap, superstrate thickness and feeding point location on the antenna performance are analyzed in TM11 mode using equivalent circuit concept. It is noted that the proposed antenna is very sensitive to the feeding point loca...

A compact microstrip bandpass filter using miniaturized hairpin resonators is presented in this letter. Two modified stepped impedance hairpin resonators connected by parallel coupling are designed for the bandpass filter. The proposed miniaturized hairpin resonator is composed of a microstrip line and rectangular ring structures between parallel high impedance lines. A big capacitance in the h...