Abstract-In this paper, a compact multiple-input-multiple-output (MIMO) antenna is proposed for ultra wideband (UWB) communication. The UWB MIMO antenna consists of two identical monopole antenna elements with a comb-line structure on the ground plane to improve impedance matching and enhance isolation. Simulation and measurement have been analysed in terms of reflection coefficient, mutual coupling, dispersion diagram, radiation pattern, peak gain, efficiency and envelope correlation coefficient. Results show that the antenna has an impedance bandwidth larger than 3.1-10.6 GHz, mutual coupling between the two ports lower than −25 dB and envelope correlation coefficient less than 0.001 across the UWB band. The proposed antenna has a compact size of 26 × 31 mm 2 . All the measured and calculated results show that the proposed UWB MIMO antenna is a good candidate for UWB MIMO systems.

A compact UWB-MIMO antenna with WLAN band notched characteristic is presented. UWB coverage is achieved with two closely spaced planar-monopole elements on the top side of the dielectric substrate with a truncated ground-plane etched on the bottom side. Isolation between the antennas is achieved by creating a current path to decouple energy between the radiation elements using a T-shaped ground stub. Notched frequency band between 5.15 and 5.85 GHz is achieved with a parasitic rectangular strip on the bottom side, which is connected to the radiating patch through a via hole. This approach yields a highly compact antenna design having dimensions of 22 3 29 3 0.8 mm 3 . Simulated and measured results confirm the antenna has an impedance bandwidth of 7.6 GHz from 3.0 to 10.6 GHz making it suitable for UWB MIMO systems.

This paper presents a compact wideband circularly‐polarized square slot antenna (CPSSA). The antenna is a coplanar waveguide feed structure with three T‐stubs toward the slot center and one semi‐circle tuning stub was etched to the feed line and modified inverted L‐shaped strips around the corners of the ground. Moreover, two spiral slots were loaded in the ground plane for exciting currents in a different direction. A prototype of the designed antenna is fabricated and measured to confirm the simulation results. A reasonably good agreement between the measured and simulated results in terms of the reflection coefficient <−10 dB and axial ratio are achieved. The 3‐dB axial ratio bandwidth achieved by the combination is from 4.35 to 8.15 GHz (60%, measured). The designed CPSSA has a compact size of 0.57λₒ × 0.57λₒ × 0.0116λₒ at the center frequency and fabricated on the FR4 substrate.

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Background: Job stress greatly affects the physical and mental health of nurses. Therefore, this study was conducted to investigate the relationship between spiritual health and job stress among nurses working in selected hospitals of Yazd University of Medical Sciences and Health Services in 2020. Methods: This was a cross-sectional and correlational study conducted in 2020 in Rahnemoun and Shahid Sadoughi hospitals in Yazd. The sample size was 203 nurses selected through random cluster sampling. Data were collected using the Pulotzin Wallison Spiritual Health questionnaire and the Tuft and Anderson Job Stress Questionnaire. Data analysis was performed using descriptive statistics, Spearman, Mann-Whitney, and Kruskal-Wallis correlation coefficient by SPSS24. Results: The mean of nurses' job stress was (109.17 ± 28.66) and the mean of spiritual health was (92.58 ± 14.80). The relationship between job stress and spiritual health was statistically significant and negative (P-value < 0.001). There was a statistically significant relationship between spiritual health and marital status(P-value = 0.0002), age groups(P-value = 0.013), work group(P-value = 0.003)s and employment status (P-value < 0.001); and between job stress and gender (P-value < 0.001), marital status (P-value < 0.001), age groups (P-value < 0.001), work experience(P-value < 0.001) and employment status (P-value < 0.001). Conclusion: In order to improve spiritual health, experts advise managers and supervisors to hold classes and seminars related to the positive effects of spiritual health regarding physical and mental health. Consequently, their job performance will improve.