Low-profile Frequency Reconfigurable Antenna Research Articles

Integrated design of large and medium‐sized low profile frequency reconfigurable antenna array

In this paper, in order to solve the limitations of conventional technology schemes, a new scheme for large and medium-sized frequency reconfigurable antenna array (FRAA) with low profile is proposed by combining advanced technologies such as new electromagnetic materials, reconfigurable antenna and integrated design. The proposed FRAA operating in X and Ku bands consists of a 4 × 4 antenna array, a w ide-band feed network, a dual-band electromagnetic band gap (EBG) plate and integrated bias network. The distance between antenna array and reflective plate has been reduced by 80.0% by applying an EBG structure. The influence of bias network on antenna performance is effectively reduced, and the performance of X/Ku two-band antenna is ensured through the integrated optimization design of the bias network, EBG reflector plate and antenna array. Both simulation and test results show that the proposed FRAA has good performance.

Design of low-profile frequency reconfigurable antenna for multiband applications

ABSTRACT An inverted G-shaped frequency reconfigurable antenna is presented. By inserting two PIN diodes in horizontal and vertical strips, we achieve multiple reconfigurable operating frequency bands in the range of 3 GHz to 10 GHz. The proposed antenna has been fabricated on low-cost FR4 substrate with 1.6 mm thickness. The overall antenna dimensions are 40 × 48 mm2 having a partial ground. It covers different wireless applications such as WLAN, WiMAX, Long-Distance Radio Telecommunications, and X-band Satellite Communication. The presented antenna is optimised using simulation while the results are validated by measuring the prototype in all cases. Results are provided in each case and discussed in detail as well. The proposed antenna will be one of the promising candidates for wireless application.

On the design of frequency reconfigurable tri-band miniaturized antenna for WBAN applications

A low profile frequency reconfigurable antenna for WBAN applications is reported. The presented antenna design utilizes switching characteristics of PIN diode to achieve frequency reconfigurability. The dimension of the proposed antenna is 0.136 λ0 × 0.131 λ0 × 0.001 λ0. The modified loop-shaped resonator, U shaped stub, and Mirrored F shaped strip provides an independent resonance for three distinct frequency bands. The application bands selected are 1.575 GHz (Global Positioning System), 2.45 GHz (Industrial, Scientific and Medical bands), and 5.2 GHz (Industrial, Scientific and Medical bands/Wireless Fidelity). The percentage bandwidth obtained is 3.17/1.83/2.69% at the said operating frequencies respectively. The simulated gain and total efficiencies are 3.26/3.47/4.04 dBi and 82/85/88% respectively. The directional radiation pattern obtained is highly suitable for off-body communication. The SAR is simulated to validate its suitability for wearable applications. The performance metrics of the fabricated prototype antenna is validated using Measurements.

Low-Profile Frequency Reconfigurable Antenna for Heterogeneous Wireless Systems

A low-profile (0.21 λ g × 0.35 λ g × 0.02 λ g ) and a simply-structured frequency-switchable antenna with eight frequency choices is presented in this paper. The radiating structure (monopole) is printed on a 1.6-mm thicker, commercially-available substrate of FR-4 ( ϵ r = 4.4, tan δ = 0.020). Specifically, it uses three PIN diodes in the designated places to shift the resonant bands of the antenna. The antenna operates at four different modes depending on the ON and OFF states of the PIN diodes. While in each mode, the antenna covers two unique frequencies (Mode 1 = 1.8 and 3.29 GHz, Mode 2 = 2.23 and 3.9 GHz, Mode 3 = 2.4 and 4.55 GHz, and Mode 4 = 2.78 and 5.54 GHz). The performance results show that the proposed antenna scheme explores significant gain (>1.5 dBi in all modes) and reasonable efficiency (>82% in all modes) for each mode. Using a high-frequency structure simulator (HFSS), the switchable antenna is designed and optimized. The fabricated model along with the PIN diode and biasing network is tested experimentally to validate the simulation results. The proposed antenna may also be combined in compact and heterogeneous radio frequency (RF) front-ends because of its small geometry and efficient utilization of the frequency spectrum.

A low profile reconfigurable antenna for defense aircrafts

In this paper a low profile frequency reconfigurable antenna is proposed that can conform to the host surface. The proposed design is a pixelated antenna structure with a grid of small metallic patches with RF switches for re-configurability. The prototype of the proposed design is designed on an FR4 substrate with the relative dielectric constant of 4.4 and thickness of 1.6 mm. This antenna is capable of resonating in three different frequencies. The prototype resonates at 10 GHz with return loss of − 12.47 dB and gain of 4.35 dB, 3.9 GHz with return loss of − 19.95 dB and gain of 3.52 dB and 2.6 GHz with a return loss of − 14.22 dB and gain of 4.26 dB. The simulated result shows that the gain of the pixel antenna on FR4 substrate ~ 4 dB comparable to gain attained by pixel antenna on substrates with low tangent loss and low dielectric constant. It is observed that the measured results are in good agreement with the simulated result.