In this letter, the numerical and experimental investigation of triangular-shaped microstrip power divider is designed for C-band applications using defected ground structure (DGS). Numerical simulations are carried out using different computer-aided design tools based on different numerical techniques, i.e., Ansoft HFSSand CST Microwave Studio. Good agreement is found between the calculated results using both HFSS and CST. A parametric study is carried out to address the effect of DGS parameters on the performance of the proposed triangular-shaped microstrip power divider. A power divider prototype is fabricated and tested experimentally. Measured results agree well with numerically calculated results.

In this letter, a microstrip fed ultra-wideband (UWB) antenna with different band rejection techniques is presented. The designed antennas consist of a defected ground plane with an elliptical slot and elliptical shaped radiating element. The measured and calculated impedance bandwidth of the proposed antenna ranges from 3 to 14 GHz for a return loss (S11) less than −10 dB. Also, it has a relatively stable radiation patterns over its whole frequency band of interest. Two different techniques have been proposed to achieve band-notch characteristic in the 5.0- to 6.0-GHz wireless local area network frequency band. The first one uses L-shaped parasitic strip into the radiating patch, whereas the other one uses two rectangular slits cut away from the ground plane creating defected ground structure. The proposed antenna is considered a good candidate for UWB applications.

This paper studies the mutual coupling effect between array elements of two- and four-element ultra-wideband (UWB) linear arrays on their performances. For simplicity, it is assumed that both antenna arrays are fed by independent microstrip lines with the same power amplitudes and equal phases. From our study, array bandwidth improvement is achieved for both array types when the mutual coupling is strong enough or inter-element spacing is small. The mutual coupling also enhances the array realized gain especially in the mid-frequency band (5–8.5 GHz) while it deteriorates the gain outside that frequency range. Proper tuning for inter-element spacing with enough mutual coupling enhances the array realized gain at most frequencies and makes it more stable across the desired frequency range. From the radiation pattern results, the grating lobes appear in UWB arrays when the element spacing is greater than two wavelengths at the upper edge frequency, 10.6GHz, or half wavelength at the lower edge frequency 3.1 GHz. Two fabricated array prototypes with corporate feed are fabricated and tested to validate the theoretical analysis. The effect of using T-junction power divider is clear on the reflection coefficient |S11|. Both numerically simulated and experimental results successfully demonstrate our analysis.

In this letter, a novel microstrip line-fed printed monopole antenna for ultra-wideband (UWB) short-range wireless communications is proposed. The proposed antenna consists of a trapezoidal-shaped patch with two elliptical-shaped cuts from its edge forming a bell-shaped cut. Experimental results shows that the designed antenna operates over impedance bandwidth 3.2–11.4 GHz for return loss S11 _10 dB, which almost covering the UWB frequency bandwidth. Moreover, the antenna has a good omni-directional radiation patterns in the H-plane with good gain flatness over the frequency range of interest. The antenna transmission characteristics at different receiving angles are also measured. By embedding a simple narrow U-shaped slot in the radiating microstrip patch, a notch in the frequency band of 5.0–6.0 GHz is obtained. The proposed antenna is considered a good candidate for UWB short-range wireless communication systems avoiding the interference of the existing wireless systems.

A novel compact ultra-wideband (UWB) printed monopole loaded with a dielectric resonator (DR) antenna is proposed. The antenna consists of a microstrip fed monopole printed on a substrate with a truncated ground plane loaded with a DR. The bandwidth is enhanced by making an inner groove inside the DR and controlling the slot width of the truncated ground.

In this paper, a novel compact butterfly shaped printed monopole antenna for ultra-wideband (UWB) applications is presented. The proposed antenna is designed with a standard printed circuit board (PCB) process for suitable integration with other microwave components. The antenna prototype is designed then fabricated and tested experimentally. The calculated impedance bandwidth of the proposed antenna ranges from 3 GHz to 13 GHz for a 10 dB reflection coefficient (S11) while the measured impedance bandwidth ranges from 3 GHz to 10.8 GHz covering the whole UWB frequency range. The measured antenna radiation patterns show relatively stable radiation patterns with almost constant gain over the whole frequency band of interest. By introducing a slit ring resonator (SRR) in the feedline, a bandstop of 830MHz from 5.0 to 5.83 GHz for band rejection of wireless local area network (WLAN) can be achieved. So, the proposed antenna is considered a good candidate for future UWB communication systems.

In this paper, a novel hybrid dielectric resonator (DR) antenna for Ultra-wideband (UWB) short-range wireless communications is proposed. The proposed antenna consists of a microstrip fed monopole loaded with a half cylindrical dielectric resonator antenna of Rogers RO3010 mounted on RT5880 substrate with a finite ground plane. The microstrip line fed monopole antenna is on the other side of the substrate. Compared to the conventional circular cylindrical DR mounted on a finite ground plane (reference antenna), the proposed antenna has a reduction in the antenna size by about 30% with a bandwidth increase by about 22% than the reference antenna. The proposed antenna has a good impedance bandwidth. In addition, the proposed antenna has a quite higher and more stable gain than that of reference antenna. Moreover, the antenna has a good omni-directional radiation patterns in the H-plane. The proposed antenna is considered a good candidate for UWB short-range wireless communication systems.

Two microstrip fed ultra-wideband (UWB) antennas with different band rejection techniques are presented in this paper. The designed antennas consist of a defected ground plane with an elliptical slot and two different radiator shapes. The first design is composed of a half circular ring radiator element while the second one uses a crescent shaped radiator. The radiators are fed by a 50- microstrip line with a tapered microstrip transition to ensure good impedance matching. The calculated impedance bandwidth of the proposed antenna ranges from 3 GHz to 14 GHz with relatively stable radiation patterns. To achieve band-notch characteristic in the 5.0-6.0 GHz WLAN frequency band, two different techniques have been implemented. The first technique uses a C-shaped slot etched in the ground plane while the other one uses another C-shaped slot in the feed line.