Monopole Antenna For Ultra-wideband Applications Research Articles

Printed Monopole Antenna with a Novel Band-Notched Folded Trapezoid for Ultra-wideband Applications

In this paper, we propose a new band-notched tapered monopole antenna for ultra-wideband applications. The antenna structure is etched on a 1 mm-FR4 epoxy substrate with dielectric constant εr = 4.4. The ground plane and radiating patch are tapered to obtain good wide impedance matching performance. Inserting two slots in the ground plane causes to greatly widen the impedance bandwidth. By embedding a folded trapezoid in an inner hole of the patch, the band-notch function can be achieved. The fabricated antenna has a small size of 18 mm × 20 mm and operates over the frequency band between 3 to 13 GHz for VSWR < 2, rejecting the undesired frequency band from 5.1 to 5.85 GHz.

Design of a Multiresonator Loaded Band-Rejected Ultrawideband Planar Monopole Antenna With Controllable Notched Bandwidth

We present a new multiresonator loaded band-rejected planar monopole antenna for ultrawideband applications. The proposed microstrip-fed antenna is composed of a flared metal plate, a truncated ground plane, and two pairs of folded strips. By applying the resonance nature of the folded strips and the associated cross coupling effects, the proposed antenna demonstrates bandstop-filter-like response with bandwidth controllability at the targeted rejection band. To illustrate the antenna operating mechanism more clearly, an equivalent circuit model consisting of RLC lumped resonators and J-inverters is discussed and extracted. The antenna input admittance calculated with the help of the equivalent circuit model agrees reasonably well with the simulated one obtained by the full-wave simulator. The design concept and the simulated and experimental results including the return losses, radiation patterns, and gain responses versus frequencies are carefully investigated throughout the paper. A parametric study in terms of the bandwidth tunability of the proposed design at the notched band is performed. The effects of the finite size ground plane are studied in this paper as well.

Ultrawideband Band-Notched Folded Strip Monopole Antenna

We propose a new band-notched folded strip monopole antenna for ultrawideband applications. This antenna is composed of a forked-shape radiator and a 50 Omega microstrip line. To achieve band-rejected filtering property at the WLAN bands, the forked-shape strips are folded back and result in a pair of coupled lines on the radiator. The length and gap width of the coupled lines primarily determine the notched frequency of the antenna. Based on the band-notched resonance, an equivalent circuit model is proposed for the antenna and the calculated antenna input admittance agrees with the full-wave simulation data. With the help of the dimensionless normalized antenna transfer function, the radiation characteristics are investigated thoroughly. The transmission responses of a transceiving antenna system and their corresponding transient analysis are discussed at the end of this paper.

A Study on Miniaturization of Printed Disc Monopole Antenna for UWB Applications Using Notched Ground Plane

In this paper, we report the detailed investigation of novel printed disc monopole antennas for ultra-wideband (UWB) applications focusing on miniaturization of the disc radiator. First, the basic property was examined for the case of a circular disc with diameter of 50mm, and it was found that the VSWR is less than 2 in the UWB band of 3.1-10.6 GHz when the feed gap length is between about -0.1 and 0.2mm. Next, in order to reduce the size of the disc radiator, various dimensions of elliptical discs were investigated. It is shown that if the dimensions of the elliptical disc are chosen appropriately, a smaller disc size antenna can be achieved. To decrease the antenna size further, a triangular notch and an exponentially curved notch on the ground plane of the antenna were examined. It is observed that the use of the notched ground is very effective and that the diameter of the circular radiator can be reduced to 17 mm. The proposed antenna has an omnidirectional pattern in the x-y plane. The influence of the notch on the radiation pattern is very small. Details of the simulation results using the FDTD method and experimental results for the proposed antenna are presented and analyzed. These features are very attractive for UWB applications.

Planar branched monopole antenna for UWB applications

AbstractDevelopment of a compact microstrip‐fed, branched monopole antenna for ultra wide band (UWB) applications is presented. By suitably embedding branches on the top edge of the strip monopole, an UWB response can be easily achieved by merging different resonances. The simulated and experimental results demonstrate that the proposed antenna achieves more than 3:1 impedance bandwidth for 2:1 VSWR criteria. The antenna exhibits nearly omni directional radiation characteristics and moderate gain in the entire band. The proposed antenna is printed on a FR4 substrate of εr = 4.4 and thickness h = 1.6 mm and having an overall dimension of 65 × 35 mm2 including the ground plane. The parameters that affect the performance of the antenna are presented and discussed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 45–47, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22045

Printed annular monopole antenna for ultra-wideband applications

A novel printed monopole antenna for ultra-wideband applications is introduced, which consists of an annular monopole patch and a trapeziform ground plane with a tapered CPW feeder in the middle. The simulated and experimental results demonstrate that this antenna achieves a ratio impedance bandwidth of more than 10:1 for VSWR≤2, and exhibits the nearly omnidirectional radiation pattern with a simple structure.

Printed circular disc monopole antenna for ultra-wideband applications

A novel and simple design of a printed circular disc monopole antenna for ultra-wideband applications is presented. The parameters which affect the performance of the antenna are investigated. Good agreement is achieved between simulation and experiment.