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This research looks at microwave devices, specifically, patch antenna along with electromagnetic spectrum, shape, mechanism, analytical methods, simulation tools, and feeding procedures. Patch antennas are distinguished by their rectangular form, with a patch on one side and a ground plane on the other. Patch antennas work by exciting electromagnetic waves inside the patch, which are subsequently transmitted into the surrounding environment. The report also outlines numerous ways for evaluating the performance of microstrip patch antennas. The electromagnetic characteristics of the antenna are analyzed using the transmission line model, cavity model, and multiport network model (MNM). The integral equations that regulate the behavior of the antenna are solved using the method of moments (MoM) and the finite element method (FEM). The spectral domain technique (SDT) is used to analyze the antenna’s frequency response, while the finite difference time domain (FDTD) approach is used to analyze the antenna’s time-domain behavior. Overall, these methodologies give a thorough understanding of microstrip patch antenna performance and may be utilized to optimize their design. Furthermore, several patch antenna feeding methods, such as probe feed, microstrip line feeding, aperture coupling, proximity coupling, and CPW feed, are investigated. Attaching a microstrip line to the patch, which is subsequently linked to the RF source, is what microstrip line feeding entails. Aperture coupling entails making a hole in the ground plane that allows the RF source to feed the patch directly. Proximity coupling is accomplished by placing a probe near the patch, which creates an electromagnetic field on the patch. Patch antenna simulation software includes programmers such as HFSS, CST, and FEKO. These tools simulate the patch antenna’s performance, including its radiation pattern, gain, and input impedance. These simulations may be used to optimize the patch antenna design for specific applications. Moreover, recent antenna trends are presented in this article. [ABSTRACT FROM AUTHOR]

This paper presents a compact and wideband square microstrip patch antenna using low cost and easy available FR‐4 substrate of ground size 30 mm × 30 mm (0.51 × 0.51λ02 at lowest resonant frequency 5.07 GHz). The radiating patch of antenna is designed by embedding three T‐shape notches of same dimension formed by two rectangular notches of size 6 mm × 5 mm and 3 mm × 2 mm. The radiating patch is optimized by parametric variation of notches and feed line. The wideband fractional bandwidth (S11 < −10 dB) of 47.2% (2810 MHz) is achieved from 4.55 to 7.36 GHz with good return loss of −47.27 dB at 5.07 GHz for an optimized dimension of notches and feed line. However, the measured fractional bandwidth of 43.9% (2340 MHz) is achieved from 4.16 to 6.50 GHz with return loss of −37.34 dB at 5.14 GHz. A stable simulated gain of 4.69 to 5.93 dBi and measured gain of 4.4 to 5.9 dBi is observed in complete resonating band. The antenna is excited by line feed of 50 Ω and simulated by IE3D simulation tool. The entire resonating band 4.55–7.36 GHz is suitable for different applications in C‐band (4–8 GHz). [ABSTRACT FROM AUTHOR]

In this article, the design and analysis of a double cylindrical dielectric resonator antenna (CDRA) of compact size 40 × 40 mm2 with extended wideband characteristics for C- and X-band applications is presented. A couple of CDRA is placed over the two adjoin rectangular slots which are excited by a modified microstrip feed line of 50 Ω. The proposed double CDRA resonates between frequency band 4.75 and14.43 GHz with 100.93% (9.68 GHz) impedance bandwidth. Two adjoin rectangularslots with a modified microstrip feed line generate two orthogonal degenerated hybrid modes (HEMx11δ and HEMy11δ), which are liable for the creation of circular polarization characteristics between the frequency band 6.62 and 8.5 GHz with 24.86% (1.88 GHz) 3-dB axial ratio bandwidth. The stable peak gain of 6.27 dB at frequency 12.62 GHz, whereas the gain of 3.31–6.27 dB and radiation efficiency of more than 86% in the entire operating band is obtained. [ABSTRACT FROM AUTHOR]

Summary: Wireless body area networks (WBAN) is used to measure patients' health conditions continuously. Different kinds of sensors are required to measure health conditions. When such types of antennas are used on the human body, they are flexible with the movements. The usage of wearable devices is currently increasing in the biomedical field. The presented wearable antenna is suitable for biomedical applications. The presented ultra‐wideband (UWB) flexible parachute shape wearable antenna is fabricated on a jeans textile substrate. The prototype antenna has a −10 dB measured impedance bandwidth of 5800 MHz (7 to 12.8 GHz) with average radiation efficiency of 75.28%. The prototype antenna's size is 40 × 40 mm2 (1.32 × 1.32 λ02 at centre frequency 9.9 GHz) and a peak gain of 4.5 dB at 12.33 GHz. The fabricated antenna is suitable for biomedical applications in X‐band frequencies and can be implemented with a low‐cost manufacturing process. The radiating element is made by conductive copper tape. Muscle‐equivalent phantoms are used to analyze the body effect on antenna performance. The radiation effect emitted by the presented antenna on the human body is calculated by the specific absorption rate (SAR) value. The maximum SAR value of the proposed antenna is 1.84 W/kg at 12.33 GHz. This leads to promising results for wearable applications related to remote health care monitoring, such as biotelemetry and mobile health with a sensor‐driven approach. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a slotted printed rectangular monopole antenna (SPRMA) is proposed that covers the entire UWB (ultra‐wideband) except for WiMAX and WLAN (802.11/a‐n). In the first stage, a rectangular monopole antenna is designed, which covers the entire UWB frequency. Then, a T‐slot is inserted in the radiating patch to have the rejection of the band containing WiMAX and WLAN (802.11/a‐n). The notch characteristics of the proposed antenna are observed from 3.0 to 3.65 GHz and 4.5 to 6.65 GHz respectively. Measured peak gain of 3.28 dBi has been observed at 4.25 GHz frequency. To show the validation of antenna, mathematical analysis using circuit theory has been also given in the paper. The prototype has been also tested inside the anechoic chamber to give the validation in real‐time environment. Several other reported antenna structures have also the same notch band in UWB with different notching methods. The proposed structure's radiation properties are compared with other reported structures proving the compactness of the proposed structure. [ABSTRACT FROM AUTHOR]

Background: Non-communicable diseases are on the upsurge throughout the world. They take a toll of 71% of overall total death, majorly contributed by cardiovascular disease. Hypertension has been a consistent risk factor for cardiovascular diseases among the various risk factors. Hypertension's asymptomatic nature makes it a silent killer; many lives are avertable if a timely diagnosis can be assured. Aims and Objectives: The aim of this study was to determine the prevalence of undiagnosed hypertension among the attendees of a sub-district hospital. Materials and Methods: We conveniently chose 100 participants of age 30 years from the out-patient department of a sub-district hospital in Gohana, Haryana. Any attendees aged more than 30 years was requested to participate in the study. The execution of the study was done in accordance to the guidelines laid in Helsinki Declaration 1975, revised 1983. Due permission was taken from the concerned authority of the study facility. After obtaining well-informed consent, data were collected through a semi-structured questionnaire. The blood pressure was measured and classified per JNC-8 guidelines. Any participant having systolic B.P. more than 140 mmHg and diastolic B.P. more than 90 mmHg on two 5 min apart readings was considered hypertensive. The descriptive analysis was done in terms of frequencies and proportions. The Chi-square test was done to determine any association of undiagnosed hypertension with selected risk factors. Results: We report a 59% prevalence of undiagnosed hypertension among study participants. The undiagnosed hypertension was statistically associated (P<0.05) with higher body mass index, less physically active, being a diabetic, alcoholic, smoker, and having a positive family history of hypertension. Only 2% of the participants knew of any health program on non-communicable diseases. Conclusion: A higher prevalence of undiagnosed hypertension even after health facility visits for any other reason warrants the standardized and universal blood pressure measurement of patients visiting health facilities irrespective of the health issue, for which they are visiting. [ABSTRACT FROM AUTHOR]