Frequency Reconfigurable Dielectric Resonator Antenna Research Articles

Dual band high tuning range frequency reconfigurable dielectric resonator antenna for sub-6 GHz applications

ABSTRACT A high-tuning range frequency reconfigurable dual-band compact cylindrical Dielectric Resonator Antenna (DRA) for 5 G Sub 6 GHz applications is presented in the proposed work. The work presented here provides compactness, frequency reconfigurability (FR), and dual-band. FR is obtained through two PIN diode switches, which operate in ON-ON, ON-OFF, OFF-ON, and OFF-OFF configurations and offer a maximum wide tuning range and a total spectrum of 44.44% and 71.49%, respectively. In the cylindrical DRA, the HE M 11 δ and HE M 12 δ modes create dual-band, while the hybrid structure and higher order mode excitation yield compactness.

Artificial Magnetic Conductor Based Miniaturized Frequency Re-configurable Dielectric Resonator Antenna for 5G and WBAN Applications

In this work a novel miniaturized frequency reconfigurable Dielectric Resonator antenna using Artificial Magnetic Conductor (AMC) surface is proposed. The prototype is set to work for 5G mid-band frequencies and Wireless Body Area Network (WBAN) applications. The work consists of two parts: firstly, the miniaturization of the prototype using AMC surface and secondly using the same AMC surface to reconfigure the frequency to another wireless application. Using AMC surface, the DR volume is reduced by 85% percent. Connecting the AMC unit cells through ideal switches (micro-trip slabs) re-configures the DR for different frequency. The overall performance observed before switching as well as after switching in both the cases is promising. The design is fabricated for performance analysis. A close agreement is reported between simulated and measured values of the reflection coefficients, radiation pattern, gain and efficiencies. The prototype has stable radiation pattern for both the operating frequencies. The impedance bandwidth values for both the resonance frequencies are 14.2% and 16% respectively. The prototype has a maximum gain of 6.8dBi and a maximum efficiency of 88%.

A Wideband-to-Narrowband Rectangular Dielectric Resonator Antenna Integrated With Tunable Bandpass Filter

A compact, frequency-reconfigurable dielectric resonator antenna (DRA) with wideband and continuously tunable narrowband states is presented. It is intended for the application scenario in the cognitive radio system. The wideband state is the sensing state and operationally covers 3.82-8.94 GHz. The narrowband states are intended to cover communications within the 5.14-5.98 GHz range, which completely covers the WLAN frequency bands. Three p-i-n diodes are employed to switch between wide and some narrowband operational states by selecting the corresponding path. A varactor diode is used to shift the operational frequencies continuously among the narrowband states. The proposed DRA consists of a rectangular dielectric resonator excited by microstrip feedline with a reconfigurable filter; it has a compact dimension: 0.31λ L × 0.41λ L × 0.06λ L , where the wavelength λL corresponds to the lower bound of its operating frequencies. The measured reflection coefficients, far-field radiation patterns, and realized gains for both operation states are in good consistent with their simulated values.

Frequency reconfigurable dielectric resonator antenna for WiMAX/WLAN applications

A CPW-fed frequency reconfigurable dielectric resonator antenna (DRA) is studied and presented for WiMAX and wireless local area network applications. The frequency tunable DRA is able to alter the frequency at three different dual bands frequency. The rectangular dielectric resonator has a permittivity of 10. Two PIN diode switches are located on the connecting lines of the network, which feeds the three dielectric resonator elements. Three dual-band modes with center frequency of 2.4 and 5 GHz in ON–ON state, 2.5 and 5.2 GHz in OFF–ON state, 3.5 and 5.8 GHz in ON–OFF state by switching of the diodes are achieved. The proposed dielectric resonator (DR) antenna has a compact size of 33 × 45 mm2 with a DR thickness of 2.8 mm. the simulation and measurement results are compared to prove the good agreement and performance of the proposed antenna. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:579–582, 2015

An Air-Gap-Based Frequency Switching Method for the Dielectric Resonator Antenna

The dielectric resonator antenna (DRA) has several advantages over metallic antennas, which may include low loss and compact design. However, few frequency reconfiguration methods exist for the DRA. This letter proposes, designs, and validates a new frequency-reconfigurable DRA that exploits the air gap effect. Here, air-filled channels are inserted between the DRA and the ground plane, and resonant frequency can be lowered by sliding metallized dielectric slugs under the resonator. The proof-of-concept prototype had a measured switching range of 24.7% and operating frequencies of 21.4 and 16.7 GHz.

Frequency-Tunable Differentially Fed Rectangular Dielectric Resonator Antennas

The frequency-tunable differentially fed rectangular dielectric resonator antenna (DRA) loaded by chip capacitors or chip varactors is investigated. Two conducting strips are attached on two opposite DRA side walls for soldering the loading elements. In each loading case, a frequency-tunable DRA with good match and stable radiation patterns can be obtained. Also, the cross-polarized field level is relatively low. Reasonable agreement between the measured and simulated results is obtained. It is found that the frequency tuning ratio can be controlled by the loading elements and the sizes of the DRA and conducting strips. In particular, for the varactor-loaded case, a frequency-reconfigurable DRA can be obtained by varying the biasing voltage of the varactors.

A Frequency Reconfigurable Dielectric Resonator Antenna Using Colloidal Dispersions

The vertical displacement of a columnar fluidic colloidal dispersion is examined as a frequency reconfigurable dielectric resonator antenna (DRA). The coaxial probe-fed structure has tunable impedance properties that are reversibly controlled by adjusting the columnar height of the dispersion. Colloidal barium strontium titanate was dispersed in hydrotreated naphthenic oil and placed at several heights into a section of polycarbonate tubing over an aluminum ground plane to demonstrate the impedance properties of this structure. Measured, simulated, and calculated results for a range of heights that corresponded to single-mode operation are provided for a design operating between 2.5 and 4.5 GHz.