Compact Ultra-wideband Patch Antenna Research Articles

A compact ultra-wide band patch antenna using defected ground structure

A compact ultra-wide band patch antenna using defected ground structure

Split-ground Compact Ultra-wide Band Patch Antenna for Wireless LTE/UMTS Operations

The lower band and mid band ‘5G’ are known to use the frequencies in the range of 600 MHz – 6 GHz worldwide, especially 3.5GHz to 4.2GHz. A new modified multi slot compact planar ultra-wideband Microstrip patch antenna with a split ground plane has been proposed in this paper. The size of the antenna occupies volume of 34x30x1.7 (1734 mm^3) which has been designed on a FR4 epoxy substrate with dielectric constant of 4.4. In order to provide dual wideband characteristics, a ‘T and G ’shaped slots with split ground plane using line feeding structure has been used. The effects on the return losses v/s frequency for the antenna using different substrates with varying dielectric constants for the same dimensions has been studied in this paper. The proposed antenna operates in dual band with first band being a narrow band ranging from 1.92GHz to 2.06GHz and the second band is an ultra-wide band which ranges from 3.40 GHz to 9.6 GHz. The split ground plane and slot size variations in the T and G slot geometry helps in retrieving the dual bands. The proposed antenna is covering applications from LTE band No 40, UMTS IMT-2000, Wimax (3.5/5.55GHz), ISM WLAN 5.2/5.8GHz and RFID etc. The direct line feeding method which uses a 50Ω line with width of W=3mm has been used for the micro-strip line. With split ground plane, coupling between the slots plays role for achieving the good bandwidth. The analysis of return loss (dB), bandwidth, VSWR (Voltage Standing Wave Ratio) of patch antenna with different substrates and variation of the sizes of slots in shapes has been performed using HFSS tool [12] and results has been studied in this paper.

A Design of Compact Ultrawideband Circularly Polarized Microstrip Patch Antenna

As it is well known, microstrip patch antennas are commonly used, because they are compact and it is easy to achieve a unidirectional radiation pattern with circular polarization. However, the bandwidth of patch antennas is quite narrow, which limits their use in ultrawideband (UWB) applications. In this communication, a wideband enhancement method based on a multimode analysis of patch antennas is proposed. By adding suitable shorting loads on the patch, the resonance frequency of the higher order modes TM20, TM30, TM40, and TM50 is decreased and combined with the dominant mode (TM10) one. These five modes provide a wide operating band. Using this bandwidth enhancement method, a compact UWB patch antenna with unidirectional radiation pattern and circular polarization is designed. The size of the patch is only $0.5\lambda _{0} \times 0.5\lambda _{0}$ and the height is only $0.1\lambda _{0}$ ( $\lambda _{0}$ is the free space wavelength at the center frequency). The simulation and measured results show that the proposed antenna has a bandwidth of 85% for S11 6 dBic from 2.2 to 5.5 GHz. The proposed design method is suitable for UWB CP patch antenna applications.

Compact filtering monopole patch antenna with dual-band rejection.

In this paper, a compact ultra-wideband patch antenna with dual-band rejection is proposed. The proposed antenna filters 3.3–3.8 GHz WiMAX and 5.15–5.85 GHz WLAN by respectively rejecting these bands through a C-shaped slit and a λg/4 resonator. The λg/4 resonator is positioned as a pair, centered around the microstrip line, and a C-type slit is inserted into an elliptical patch. The impedance bandwidth of the proposed antenna is 2.9–9.3 GHz, which satisfies the bandwidth for ultra-wideband communication systems. Further, the proposed antenna provides dual-band rejection at two bands: 3.2–3.85 and 4.7–6.03 GHz. The radiation pattern of the antenna is omnidirectional, and antenna gain is maintained constantly while showing −8.4 and −1.5 dBi at the two rejected bands, respectively.