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A compact 4 element MIMO antenna operating in three Sub-6 GHz 5G bands is proposed. The single element antenna consists of a square-shaped patch where circular and rectangular-shaped slot cuts are incorporated. The single element is symmetrically arranged along the horizontal direction and in mirrored fashion along the vertical and diagonal direction. The 4 element MIMO antenna achieves a symmetric structure on top with the connected ground at back. With no extra isolation element, the proposed FR-4 based design achieves compact size of 0.39λ02 (f0 = 3.72 GHz) operating in three frequency bands ranging from (2.65%) 3.72–3.82 GHz, (2.33%) 4.65–4.76 GHz and (4.75%) 6.16–6.46 GHz. The satisfactory isolation amongst inter-elements (≥ 16 dB) with directional radiation pattern and an average gain of 2.5 dBi is attained for proposed bands. Furthermore, the antenna meets the MIMO diversity criteria by achieving DG > 9.7, ECC

A compact dual parallel slotted-patch antenna having a single offset feed on the corner side is presented. The antenna geometry comprises parallel and horizontal coupled S dual slotted structure at the top, with a complete ground plane at the bottom, which is oriented to enhance the multiband frequency bands. The patch is patterned on an FR4 substrate having a dielectric constant of 4.4 and loss tangent of 0.02. The antenna has overall dimensions of 36 × 28 × 1.6 mm3, with an offset feed which is optimized to achieve 50 Ω impedance matching. The proposed antenna is simulated using a FEM-based high-frequency structure simulator, after which it is optimized, fabricated, and measured, with the simulated and measured results showing good agreement. The proposed compact antenna resonates in the pentaband frequency range which includes 2.00–2.16 GHz local TV transmission, 3.14–3.23 GHz for radio-frequency identification and detection, and 4.34–4.61 GHz for long-distance radio telecommunications. The antenna shows good gain ranging from 0.5 to 3.5 dBi with omnidirectional and bidirectional radiation patterns, making it suitable for its use in wireless applications with space constraints.

The compact slotted antenna having offset feed radiating in the multi-frequency bands is proposed. The antenna geometry comprises of a vertical and horizontally coupled slotted structure at the top with a complete ground plane at the bottom to achieve the proposed application bands. The patch is patterned on the FR4 substrate having a dielectric constant of 4.4 and loss tangent of 0.008. The antenna has an overall dimension of 0.18λ × 0.15λ mm2 (f = 1.52 GHz) with offset fed which is optimized to achieve 50 Ω impedance matching. The proposed compact antenna resonates in pentaband frequency bands which includes 1.52–1.60 GHz for GPS (ISM band in India), 2.97–3.02 GHz for Radio frequency identification and detection, mobile communication, logistics, manufacturing, transportation and healthcare, 3.73–3.84 GHz for Amateur Fixed Mobile except aeronautical mobile (R), 4.42–4.52 GHz for radio communications, TransferJet USB Adapter (Toshiba Corporation), and 4.83–4.96 GHz for Aviation Private Land Mobile applications. The proposed antenna has demonstrated a decent gain ranging from 1.07 to 3.92 dBi having omnidirectional and bidirectional radiation patterns, hence, making it suitable for various wireless applications.

In this paper, a novel multiband coplanar waveguide-fed slotted transparent antenna is presented. The structural design of the radiating element is based on the semicircular curves in the form of slots on the patch to achieve multi-band characteristics with improved bandwidth. The overall structure having a size of λ0/2.67 × λ0/2.11 achieves transparency and a lightweight due to the presence of Plexiglas as a substrate material and AgHT-8 as a conductive material including the circular slotted patch and related CPW feeding line at the center frequency of the lowest operation band. The proposed antenna has the multiband operation characteristics with the center frequencies of 2.58 GHz, 3.67 GHz, 6.2 GHz having the impedance bandwidth of 19.84% (2.27—2.77 GHz), 1.76% (3.61—3.74 GHz) and 53.58% (4.50–7.79 GHz) respectively. The agreement between the numerical computation and measurement results of RF performance characteristics point out the technical potential of the proposed optically transparent antenna for short range multiband versatile wireless applications.

A novel wide slot transparent circularly polarized antenna is illustrated in this paper. Circular polarization is achieved by using a wide slotted S-shaped loop with diagonally trimmed edges, two separate mirrored U-shaped slots with feed location at the center of the conductive patch. Conductive oxide AgHT-8 is used as a feeding patch over a 1.48 mm thick transparent plexiglass substrate (er = 2.3, tan δ = 0.000379). The antenna operates in the band spanning from 0.80 GHz - 1.05 GHz (~27.47%) with the axial ratio (AR) less than 3 dB within the same band. Numerical studies have been carried out to analyze the performance parameters of the antenna such as reflection coefficient, gain, axial ratio, radiation pattern and it has been observed that the results are satisfactory for RFID applications as an optically transparent CP antenna.

With the emergence of smart devices, the antennas that can fulfil the requirements of such devices are very much in demand. As the devices should be connected to the internet, antennas that are aesthetically good and easy to interface anywhere on the routers or repeaters are needed. One of the solutions to this problem is by using transparent antennas that are visibly neutral and can be placed anywhere in the system. Transparent antennas integrated with dielectric resonator (DR) elements lead to fewer conduction losses due to the high dielectric constant of DR, and so an antenna resonating in the frequency band of 2.4 GHz (IEEE 802.11) WLAN applications is proposed that was simulated using Ansys High-Frequency Structure Simulator (HFSS) software. The optical transparency along with wide impedance bandwidth (31.26%), directional radiation pattern, gain and efficiency values greater than 1.5 dBi, and 75%, respectively makes the antenna suitable for smart wireless applications. The DRA fabricated using transparent material AgHT-8, Plexiglas, and Borosilicate glass show good agreement with the simulated results.

Medicinal plants and their properties are significantly affected by various abiotic stressors amongst which, hazardous high-frequency mobile communication radiation spectrum become one of the prominent causes. Such radiation significantly affects the synthesis of bioactive compounds, plant health, and herbal yield. The presented investigation checks the effect of microwave radiations (1800 MHz frequency) on the fungicidal activity of Jasminum grandiflorum L. plant extract against Aspergillus niger, Aspergillus flavus, Aspergillus fumigatous, Alternaria alternata, Malassezia pachydermatis, and a mold Candida albicans. The presented investigation was held by Agar diffusion and Broth dilution assays against selected fungal strains. The finding revealed that antimicrobial potential was raised for all selected fungal strains upon exposure to radiation for 24 h which was deteriorated upon long-term exposure of 36 h and more. This indicates the rise in secondary metabolite synthesis due to induction of self-defense property of plants under radiation stress for the initial period although antifungal activity was significantly declined upon long-term exposure. The significant deterioration was reported as a 44.44% decline in ZOI and a 46.77 % raise in MIC for Alternaria alternata upon 48 hours of exposure. Such periodic decline in the antifungal potential of the exposed plant was reported against other fungal strain which was 41.17, 45.3, 40.7, 52.8, 44 % decline in ZOI whereas 69.21, 50.61, 36.47, 42.04, and 50.92 % of raise in MIC of extracts against Malassezia pachydermatis, Aspergillus niger, Aspergillus flavus, Aspergillus fumigatous, and Candida albicans, respectively.

In this article, a retail management system (RMS) called Shopwell is developed which keeps track of the expiry date of products along with the total expenditure analysis through Python, MySQL, and Android Studio where customers can keep track of the budget utilized for buying the products like groceries, cosmetics, and medication and it alerts when the product expiry is near while shopping online or offline. The customers hardly keep track of expiry dates on products and sometimes it is hard to keep track of total spending over a while. The proposed system can be linked with any retail business and comes in handy in the form of an app that can be installed on mobiles, tablets, and laptops. Once the retail business ties up with Shopwell, the bill which is created after shopping generates a link which directly links to the app once clicked by the customer when shopping online otherwise the link is established once the cashier scans the QR code available in the customer's app after scanning the products over offline mode. Once the app has the required data of the purchased items, it assists the customers to keep a record of the purchase details chiefly on the expiration date and the total expenditure thus avoiding consumers to stop using out of date products while keeping the daily budgets within stipulated limits.

CPW fed transparent dual-ring antenna backed with an Artificial Magnetic Conductor (AMC) is presented. The dual ring transparent antenna resonates in the frequency band of ISM application having an impedance bandwidth and average gain of 5.46 – 5.96 GHz (8.8 %) and 1.1 dBi, respectively. The AMC is embedded on the lower side of the antenna to enhance the bandwidth and gain of the antenna where analysis in terms of varying the AMC array elements is carried out. The overall transparency of antenna and AMC structure is achieved by using AgHT-8 and Plexiglas which is simulated by using CST software to check the performance of the antenna in terms of reflection coefficient, radiation pattern, and reflection phase. Performance comparison between non-AMC antenna structure and 4×4 AMC array incorporated structure shows impedance bandwidth and average gain of 5.3 – 6.0 GHz (12.4%) and 5.47 dBi respectively, within that bandwidth makes the latter suitable for ISM band applications.

A smart parking system using Raspberry Pi and android app access is proposed in this article. An automated smart parking system which provides the user to pre-book along with on the spot booking facility of parking spaces available around the area is implemented. The system also helps to store the user’s information in database which enables for fast parking access thus reducing the traffic congestion. The hardware is realized using Raspberry Pi and IR sensor. In addition, the system is controlled through an app which is made using Kodular App Development tool, that helps the user to keep track of the updates about available parking spaces. The scalable and precise database can be created on firebase and host it on an application in real-time which is useful to store data in a json format (bucket format). The system is a perfect partner for people to book the parking spaces at their ease from remote locations without wasting time and avoiding traffic congestion.

In the recent years, the Textile antenna design has become an attractive research area to its persistent healthcare applications. Wearable antennas are becoming widespread and their demands are significantly increasing in the sense of their use in smart clothes in wireless communications. The use of fabrics in flexible antennas necessitates description of their properties. However, very less evidence can be establish on the electromagnetic possessions of consistent textiles. In addition, textile fabrics are porous, aelotropic and compressible materials that thickness Low pressure may change density. Consequently, it is imperative to recognize how these appearances affect the performance of the antenna to minimalize adverse effects.

A four-port MIMO antenna array with wideband and high isolation characteristics for imminent wireless systems functioning in 5G New Radio (NR) sub-6 GHz n77/n78/n79 and 5 GHz WLAN bands is proposed. Each array antenna element is a microstrip-line fed monopole type. The novelty of the antenna lies in loading an “EL” slot into the radiating element along with two identical stubs coupled to the partial ground in order to improve the impedance matching and radiation characteristics across the bands of interest. To further attain high port isolation without affecting the compactness and radiation performance of each antenna element, the technique of introducing an innovative un-protruded multi-slot (UPMS) isolating element (of low-profile 2 × 19 mm2) between two closely spaced antenna elements (with an edge-to-edge distance of approx. 0.03λ at 4.6 GHz) is also presented. Besides demonstrating a small footprint of 30 × 40 × 1.6 mm3, the proposed four-port MIMO antenna array has also shown wide 10-dB impedance bandwidth of 58.56% (3.20–5.85 GHz), high isolation of more than 17.5 dB, and good gain and efficiency of around 3.5 dBi and 85%, respectively, across the bands of interest. Finally, the MIMO performance metrics of the proposed antenna are also analyzed.

A novel dual branch multiband compact slotted antenna for digital broadcasting, wireless and sub 6 GHz 5G is presented. Antenna achieves multiband characteristics at (750–790 MHz) Digital broadcasting, (1.41–1.45 GHz) wireless medical telemetry, (2.10–2.14 GHz) Universal Mobile Telecommunication Service (UMTS), (3.44–3.51 GHz) WiMAX/sub 6 GHz 5G, (3.80–3.87 GHz) Sub 6 GHz 5G, (5.17–5.20 GHz) wireless local area network (WLAN) and (5.97–6.38 GHz) fixed satellite communication by introducing slots in the form of inverted U and E shape having varied branch lengths and full ground plane. The antenna has an overall size of 30 × 30 × 1.6 mm3. The proposed antenna achieves compact operation along with an omnidirectional radiation pattern having gain and efficiency in the range over 1.1 dBi and 78% for the proposed frequency bands. The antenna is fabricated after optimizing the geometrical dimensions where measured results match well with simulated ones.

Rapid increase in wireless communication systems has boom the demand for antennas. Antenna with increased gain, increased bandwidth, small size and low profile are mostly preferred in recent communication links. One such method to perform is fractal simulation of Microstrip Patch Antenna. This paper presents a design and simulation of fractal in simple circular patch antenna up to three iterations. With the aim of increasing gain, minor modifications are performed in the design after final iteration. Following design is made using HFSS software with the substrate material as FR4 having 4.4 dielectric constant and 1.6mm height. Possessed antenna gives a wideband up to 18% between 5.32-6.35 GHz frequencies for WiMAX/WLAN applications.

Today there is demand to monitor environmental factors almost in all research institutes and industries and even for domestic uses. The analog data measurement requires manual effort to note readings and there may be a possibility of human error. Such type of systems fail to provide and store precise values of parameters with high accuracy. Analog systems are having drawback of storage/memory. Therefore, there is a requirement of a smart system which is fully automated, accurate and capable enough to monitor all the environmental parameters with utmost possible accuracy. Besides, it should be cost-effective as well as portable too. This paper represents the Wireless Sensor(WS) data communication using DHT11, Arduino, SIM900A GSM module, a mobile device and Liquid Crystal Display(LCD). Experimental setup includes the heating arrangement of DHT11 and transmission of its data using Arduino and SIM900A GSM shield. The mobile device receives the data using Arduino, GSM shield and displays it on LCD too. Heating arrangement is used to heat and cool the temperature sensor to study its characteristics.

A Completely Automated Public Turing test to tell Computers and Humans Apart is a test use to determine whether the user is a human or a malicious computer program. In simple terms CAPTCHA is a program that can generate and grade tests that most humans can pass, yet current computer programs can't pass. They can be found as blurred or distorted random images, in free email signups, online polls or commenting on blogs; these images are difficult to recognize by computer programs but easy for most humans. They work as basic tool for preventing Denial of Service, brute force attacks and advertising spams. CAPTCHAs have evolved from simple text based to recent advancements like audio and visual tests. Text based CAPTCHAs have been broken successfully with the help of Optical Character Recognition and every approach is vulnerable against laundry attacks or redirection. The suggested approach 'Drag and Drop CAPTCHA' or 'DnD' is inclusive solution against OCR and laundry attacks. This HIP challenge uses conventional mouse events to recognize human intervention proof. If an attacker computer knows the answer of test but it can't pass this test without human intervention. This technique can be considered as an Artificial Intelligence challenge. It creates win-win situation either this tough AI problem gets solved or DnD technique is distinction tool for human & computers.