Sub-6 GHz frequency band offers enhanced channel capacity and adequate bandwidth for wireless 5G automotive applications. Such applications demand user equipment antenna terminal with multiple resonating frequencies with acceptable gain to ensure the reasonable data rate for effective communications. To meet these specific requirements a H-Shaped fractal slot patch antenna with shorting metal strip is presented for WLAN/WiMAX and sub-6 GHz 5G wireless applications. Further, Whale Optimization Algorithm (WOA) is used to find the optimum position for a shorting strip placed between the fractal slot patch and ground. The proposed antenna has been evaluated with a set of representative numerical simulations have been done as per design specifications. The projected antenna resonates at S-band and C-band frequencies aroundn41 band, n46 band and n78 band. The antenna has a peak gain of 13.2 dB in the resonating range. The measured result confirms the accuracy of antenna design and results are quite promising.

The present paper reports on the development of a Novel Patch Antenna Array for 4.9 GHz Public Safety WLAN applications. In today’s era of advanced technology, high speed video surveillance is very crucial from security point of view. Public safety surveillance services below 1 GHz are mainly used in voice surveillance services, whereas 4.9 GHz Public Safety WLAN is used for video surveillance services. Accordingly, in this work, 2×2 element antenna array is designed on FR4 substrate using modified triangular patch antenna element with improved gain to the tune of 6.69 dBi. In this research work, biologically inspired Whale Optimization method is used in combination with polynomial curve-fitting technique for the optimization of three different geometrical dimensions of the patch antenna element. The optimized element is further modified geometrically by corner rounding and cut in feed to improve its performance including gain. The proposed antenna array resonates at 4.9 GHz covering 120 MHz bandwidth with an achievement of -15.87 dB reflection coefficient and high gain. Results of simulation study are validated with measured results. The uniqueness of the proposed design lies in the achievement of a large gain using simple patch antenna array designed on readily available low cost FR4 substrate making very easy fabrication. Such an attempt has been rarely reported in the literature. However, the results of present investigations are quite convincing.

An antenna is designed in a multi-input multi-output configuration composed of four radiating elements embedded with semi-circular cuts for sub-6 GHz 5G automotive applications. The performance of the proposed design has been enhanced with the utilization of the concept of partial ground. The antenna covers the −10 dB impedance bandwidth in the frequency spectrum of sub-6 GHz, which includes 0.9 GHz, 3 GHz, and 4.7 GHz. The proposed design exhibits a wide bandwidth of 4.8 GHz, ranging from 0.7 GHz to 5.5 GHz with a peak gain of 8.8 dB in the resonating band. The isolation between the elements is well below −15 dB, and to maintain this high isolation, the antenna elements are placed at an optimized distance from each other with independent partial ground planes. The proposed design is also fabricated, and the measured results have been compared with those obtained in a simulated environment. It has been observed that both results are quite promising and well-comparable. The size of the proposed design is about (28 × 28) cm2 as the first resonating frequency is 0.9 GHz. Nevertheless, the proposed design is suitable to integrate on the rooftop of the modern passenger cars with 5G automotive wireless applications.Cite this article as: A. Kumar, B. Chandra Sahoo, G. Singh, S. Ranjan Mishra, A. Sharma, and R. Kumar, “A 4-port semi-circular arc slotted MIMO antenna for sub-6 GHz 5G automotive wireless communications,” Electrica, 25, 0150, 2025. doi: 10.5152/electrica.2025.24150.

Background: Tuberculosis (TB) is a leading cause of morbidity and mortality in the world and especially in India. MDR TB has emerged as a major challenge in TB control in India. The prevalence of MDR TB is on the rise in India. We did this study to see the prevalence of MDR TB in 3 districts of Himachal Pradesh and to study the factors affecting treatment outcomes.Methods: The period of the study was from January 2019 to December 2019. We collected data of MDR TB patients from district TB offices of Solan, Bilaspur and Hamirpur. Information from patients was collected through questionnaires while interviews were conducted with district project officer and other health officials and documents, brochures, etc. were collected from Solan, Hamirpur and Bilaspur.Results: Overall prevalence rate of MDR TB in our study was 3.14%. Among new TB cases, the prevalence rate of MDR TB was 2.42% (81/3345), and among old treated cases was 9% (37/411). 31% MDR TB patients were old treated while 69% patients had no previous treatment history. The default rate was low in our study (0.84%) while 8 (6.4%) patients had treatment interruption but for less than 15 days.Conclusions: The prevalence in our study is comparable to the national drug resistance survey. Early detection, timely treatment and contact tracing is vital in decreasing the MDR TB cases. Better supervision, constant monitoring, proper counselling and timely identification and management of adverse effects of the drugs will improve the treatment outcome among MDR TB patients.