Design of Flexible 3.2 GHz Rectangular Microstrip Patch Antenna for S-Band Communication

Abstract

This paper presents the design, simulation, realization and analysis of flexible microstrip patch antenna for S-band applications. The proposed design also adopts the conformal structure by utilizing flexible substrate. Conformal or flexible structure allows the antenna to fit with any specified shape as desired. The antenna patch dimensions is 43 mm × 25 mm without SMA connector. The patch is etched on the flexible dielectric substrate, pyralux FR 9111, with a relative dielectric constant of εr = 3 and the thickness of substrate, h = 0.025 mm. The antenna is designed to resonate at 3.2 GHz. The return loss (RL) of the simulation is -35.80 dB at the center frequency of 3.2 GHz. The fabricated antenna prototype was measured at different bending angles scenarios including 0º, 30º, 60º, and 90º. The measurement of antenna prototype shows that the center frequency is shifted to the higher frequency of 3.29 GHz, compared to the simulation result. Among these scenarios, measurement at bending angle of 90º gives the best performance with RL = - 31.38 dB at 3.29 GHz, the bandwidth is 80 MHz, and the impedance ZA = 48.36 + j2.04 Ω. Despite a slight differences from simulation results, the designed antenna still performs well as expected.

A Subtlety of Sizing the Inset Gap Width of a Microstrip Antenna When Built on an Ultra-Thin Substrate in the S-Band

“…Having said that, we see that our directivity is comparable to other references. Our bandwidth (BW) is similar to the declared BW of another Pyralux-based antenna [ 16 ] and the antenna with a polymeric substrate in [ 8 ] and is slightly smaller than that in [ 5 , 6 , 9 ], but we suspect that part of the lower value is also due to the use of a -transformer in our design. As can be seen in Table 3 , most of the other references did not quantitatively specify the beamwidths obtained by their antenna models, while our beamwidths were equal or wider than 90 in both major cut-planes.…”

“…The case is that in most papers, IRMA has been built on a relatively thick substrate (such as FR4), and the inset gap width did not appear to be a sensitive variable to set up. However, when it comes to designing an IRMA on a Pyralux sheet as a substrate, we have not found enough verifiable (i.e., reproducible) reports that can be taken as a certain reference [ 15 , 16 ], especially using such a thin substrate on relatively low microwave frequencies such as the S -band. During this work, somewhat unexpected findings were encountered that we feel are relevant to share.…”

“…In contrast, in [ 24 ], , while the circuit was also built on FR4. Of the few references that used Pyralux, in [ 15 ], , while in [ 16 ], . At this point, the optimal ratio of and the impact of g was not clear and had to be further investigated.…”

Methodology and Laboratory Measurements of Miniaturized and Improved Antenna Loaded With Circular Spiral-Line Structures (CSLS) Linear and Triangular Planar Arrays for Radar Applications

“…Electromagnetics has advanced tremendously, notably in antenna structures. This can be attributed mostly to the introduction of metamaterial (MTMs), or artificial negative index medium.MTMs are synthetically electromagnetic materials composed of metallic components organised in periodic patterns, smaller than the wavelength of the incident electromagnetic (EM) wave [25 -30].There is a huge need for MTM because of the importance of size miniaturisation and mutual coupling reduction of antennas in modern communication devices, microwave, and radar applications.Various techniques have been employed to reduce the size and improve the characteristics of antennas [31][32][33][34][35].The antenna may be more compact with a reactive dielectric constant.The use of MTMs is the most current development in antenna downsizing.Planner MTMs are frequently utilised for minimizing the antenna size and enhance its parameters [33][34][35][36]. In the present paper,a miniaturised and enhanced horn antenna that is loaded with a linear or triangular planar array of CSLS is introduced and analyzed.…”