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There is a great military, space, and industry need for wireless systems that can operate under extreme conditions such as high temperatures and harsh chemical environments. Some of the applications inc lude planetary rovers for space exploration missions, wireless systems for mining and oil drilling applications, monitoring combustion turbines, and wireless environmental monitoring of first responders. Since antennas are the most critical components of a wireless system, design of antennas capable of surviving harsh environments is significant for overall system reliability and efficient communication. Yttria-Stabilized Zirconia (YSZ) is a ceramic, which has been recently used in a wide variety of gas sensing, biomedical, and thermal applications. YSZ has properties of high temperature tolerance, moisture resistance, high strength and corrosion resistance, and structural stability. One of the recent applications of YSZ is its utilization as a substrate material in the design of patch antennas. The electrical properties of YSZ allows for designing antennas with compact form factor and high efficiency due to high relative permittivity and low loss tangent. 

Zirconia Ribbon Ceramic (ZRC) is a commercially available ceramic that can be a potential low-loss substrate for radio frequency (RF) devices suitable for high temperatures and harsh environmental conditions. In this paper, the RF characteristics of ZRC are determined in the frequency band of 0.5 GHz to 5 GHz. A T-resonator is designed and fabricated for the transmission coefficient measurements to obtain complex permittivity (dielectric constant and loss tangent) values of the material. The dielectric constant is shown to be steady at 32.2, while the loss tangent is found to be at 0.001 in the band of interest. 

This research proposes an inkjet printed dual-band dual-sense circularly polarized antenna using CPW-feeding on PET substrate. The antenna is designed and optimized using ANSYS HFSS, which operates at 4.01 GHz - 5.05 GHz (22.96%) and 6.23 GHz - 7.58 GHz (19.55%) with a return loss of <−10 dB. On top of that, the antenna shows an axial ratio of less than 3 dB at 4.23 GHz - 4.62 GHz (8.81%) and 7.11 GHz - 7.36 GHz (3.45%), whereas left hand circular polarization (LHCP) is observed in the first band and right hand circular polarization (RHCP) is observed in the second band. The overall dimensions of the antenna is x x , where is the free-space wavelength at the lowest circular polarization frequency. Measurement of the fabricated version shows good agreement with the simulated version. To the best of author’s knowledge, this proposed design is the first circularly polarized … 

In this paper, a Multi-Input Multi-Output (MIMO) antenna of 4 monopole elements is presented on Zirconia Ribbon Ceramic (ZRC) substrate. Utilization of this substrate material allows an implementation of an antenna system that is able to withstand harsh environments and high temperatures due to inherent substrate characteristics. The proposed MIMO design supports an operational antenna bandwidth from 2.44 GHz to 2.55 GHz with a center frequency around 2.5 GHz covered by all 4 antenna elements. High antenna isolation below -15 dB is obtained among the ports. The antenna also provides a peak gain over 3 dB through the entire band of interest (3.34 dB at 2.5 GHz) and low cross-polarization. 

In this paper, a simple, and compact CPW-fed circularly polarized antenna is presented. The proposed antenna consists of a modified “S” shaped patch which has slots in three different places along with a slot in the ground plane. These slots contribute in increasing the bandwidth of the axial ratio. The antenna has a 3 dB axial ratio bandwidth of 10.47% (4.07 GHz–4.52 GHz) and an impedance bandwidth of 17.53% (3.8 GHz – 4.53 GHz) covering the full region of axial ratio band. Moreover, this antenna is designed using PET paper which makes it flexible in nature and the first flexible antenna in discussed frequency range to the best of author’s knowledge. 

A novel high gain full duplex flexible antenna using PET paper and foam is presented for 5.8 GHz. Two rectangular patches are placed on top layer whereas bottom layer has defected ground structure printed on it. Patches are fed with inset line feeding. This antenna works effectively from 5.75GHz to 5.81 GHz for full duplex purpose while maintaining a radiation efficiency of 98.6% and peak gain of 8.78 dB at 5.8 GHz. This antenna is believed to be first proposed antenna which is flexible and full duplex with such high gain while working at 5.8 GHz. It also has simple structure, low cost, light weight along with good isolation and gain, which eventually makes it a good candidate for 5.8 GHz full duplex applications. 

As the advancement of wireless devices and their applications progress, it is important to produce novel aspects of a usual design to expand their capabilities. One such application could be for extreme circumstances that would include high temperatures. In order to approach this issue, a new substrate has been proposed to implement high-temperature devices. Zirconia Ribbon Ceramic (ZRC) is made of YSZ with high temperature tolerance, smooth surface, moisture resistant, mechanically robust, and low thermal mass properties [1] . Recent publications has demonstrated the suitability of ZRC for implementing functional devices [ 1 –​3 ]. Due to this material’s durability and capability of resisting high temperatures, it provides a desirable opportunity of applying this material as a substrate for patch antenna applications. The application of this material, however, requires the understanding of its electrical properties and behavior. This proposed material has a high relative permittivity and a low loss tangent as compared to traditionally available substrates. The high dielectric constant of ZRC along with low loss characteristics allows for realizing efficient wireless systems with smaller form factor. In this study, a wideband patch antenna on ZRC substrate is proposed for high-temperature environments. The antenna operates within 1.89 GHz–3 GHz frequency range, and can be used for WLAN, ISM band, and S-band applications. 

In this paper, a slotted circular ultra‐wideband (UWB) microstrip patch antenna is reported. The antenna is designed, simulated, fabricated, and tested experimentally. The antenna operates over a 4.0‐40 GHz (164% fractional bandwidth) range with a return loss of 10 dB and voltage standing wave ratio (VSWR) < 2. The designed monopole antenna is of dimensions 28.1 mm × 17.1 mm with an electrical size of 0.37 λ × 0.23 λ at 4 GHz frequency. The antenna is fabricated on FR‐4 substrate with a dielectric permittivity of 4.4, loss tangent of 0.02, and a thickness of 1.4 mm. The designed antenna exhibits nearly omnidirectional radiation patterns over the entire impedance bandwidth with more than 2.8 dB peak gain for the entire frequency range and 75% of average radiation efficiency. The presented antenna can be used in UWB communications along with C‐band, X‐band, K_u‐band, K‐band, K_a‐band, WLAN, and future wireless applications.