This paper exhibits a low profile dual-polarized MIMO antenna with high isolation to meet the requirements of 5G smartphones. The integration between a vertically polarized slot and a horizontally polarized slot is investigated and applied for 28 GHz dual-polarized smartphone antenna. The antenna is combined with metasurface (MTS) to achieve high gain and more directivity. In order to design the metasurface, the characteristic mode analysis is used to investigate the performance of MTS at 28 GHz. The proposed antenna achieves high isolation coefficients better than 40 dB and cross polarization lower than -40 dB from simulated and measured results. The isolation between elements is achieved without any additional decoupling techniques. The proposed MTS slot antenna operates with 4 GHz bandwidth (26-30 GHz) with a realized gain of 11 dBi and efficiency of 90%. Four antennas (with eight ports) are positioned orthogonally at the corners of the mobile PCB to serve MIMO for 5G applications. The effect of MIMO antenna on the human is taken into consideration in power density term. Furthermore, the housing and components of smartphones are taken into our consideration in this paper.

A transparent antenna array based on silver sandwiched indium tin oxide (AgITO) heterostructure thin films is presented. The AgITO is sputtered on both sides of soda-lime glass (SLG) substrate, and the three thin films deposition parameters are optimized to obtain very low ohmic interfacial contact resistance of less than 1 Ω/Sq. AgITO promotes thin film-based transparent microstrip structure of the proposed antenna array as well as the transparent T-junction power divider. Furthermore, AgITO microstrip as well as opaque single element antenna as reference antennas for a transparent array are presented. The proposed array has wide bandwidth promoting radio frequency energy harvesting at Wi-Fi 2.4, LTE 2600, WLAN, WiMAX and the expected 5G mid-bands. Moreover, it could be functionalized for wireless transmission within the previously mentioned bands. The transparent AgITO array has 5 dBi gain value against 2.3 dBi for the transparent AgITO single element antenna at 5.8 GHz. The array was utilized for radiofrequency energy harvesting, obtaining DC output volt=161.4 mV with a conversion efficiency of 32.9% at 5.8 GHz with RF received power of -10 dBm.

Museum contents are vulnerable to bad ambience conditions and human vandalization. Preserving the contents of museums is a duty towards humanity. In this paper, we develop an Internet of Things (IoT)-based system for museum monitoring and control. The developed system does not only autonomously set the museum ambience to levels that preserve the health of the artifacts and provide alarms upon intended or unintended vandalization attempts, but also allows for remote ambience control through authorized Internet-enabled devices. A key differentiating aspect of the proposed system is the use of always-on and power-hungry sensors for comprehensive and precise museum monitoring, while being powered by harvesting the Radio Frequency (RF) energy freely available within the museum. This contrasts with technologies proposed in the literature, which use RF energy harvesting to power simple IoT sensing devices. We use rectenna arrays that collect RF energy and convert it to electric power to prolong the lifetime of the sensor nodes. Another important feature of the proposed system is the use of deep learning to find daily trends in the collected environment data. Accordingly, the museum ambience is further optimized, and the system becomes more resilient to faults in the sensed data.

IoT system becomes a hot topic nowadays for smart home. IoT helps devices to communicate together without human intervention inside home, so it is offering many challenges. A new smart home IoT platform powered using electromagnetic energy harvesting is proposed in this paper. It contains a high gain transmitted antenna array and efficient circularly polarized array rectenna system to harvest enough power from any direction to increase lifetime of the batteries used in the IoT system. Optimized energy consumption, the software with adopting the Zigbee protocol of the sensor node, and a low-power microcontroller are used to operate in lower power modes. The proposed system has an 84.6-day lifetime which is approximately 10 times the lifetime for a similar system. On the other hand, the proposed power management circuit is operated at 0.3 V DC to boost the voltage to ~3.7 V from radio frequency energy harvesting and manage battery level to increase the battery lifetime. A predictive indoor environment monitoring system is designed based on a novel hybrid system to provide a nonstatic plan, approve energy consumption, and avoid failure of sensor nodes in a smart home.

In the past decade, the majority of the launched satellites have a weight exceeds 1 Ton. Its development takes a long time, high cost, and has a large risk of failure, and does not allow for testing new technologies to avoid the mission's failure. From these points of view, space-tested technologies were preferred to mitigate the risk of failure. Our goal is to build and test our own S-band communication subsystem for CubeSat. The system should be developed with reliable and compact hardware and flexible and efficient software. It consists of passive components such as the antennas and the filters and other active components. The passive components are designed, fabricated and measured while the active components are based on commercial components. In this paper, two antenna boards are designed; one board faces the earth and the other board lies on the opposite side. Each board has two antennas; transmitter and receiver antennas. The transmitter/receiver antennas are operating in the downlink /uplink at frequency bands from 2.2 GHz to 2.29 GHz and from 2.025 GHz to 2.11 GHz, respectively. This configuration keeps the communication between the CubeSat and the ground station to facilitate the de-tumbling process of the CubeSat. The second component is the filters that separate the transmitter from the receiver. The two filters have high roll off and narrow fractional bandwidth within a compact area. The transceiver system is based on the analog devices chip AD9361 controlled by zynq-7000 FPGA. The output RF signal is amplified to approach 33dBm output power to the antenna port via QORVO chip that operates in the range from 700MHz to 2700MHz. The antennas and filters are fabricated and tested where good results are noticed so that they are ready for integrating with the whole CubeSat communication subsystem.

This article presents an in-depth investigation of wearable microwave antenna sensors (MASs) used for vital sign detection (VSD) and lung water level (LWL) monitoring. The study looked at two different types of MASs, narrowband (NB) and ultra-wideband (UWB), to decide which one was better. Unlike recent wearable respiratory sensors, these antennas are simple in design, low-profile, and affordable. The narrowband sensor employs an offset-feed microstrip transmission line, which has a bandwidth of 240 MHz at −10 dB reflection coefficient for the textile substrate. The UWB microwave sensor uses a CPW-fed line to excite an unbalanced U-shaped radiator, offering an extended simulated operating bandwidth from 1.5 to 10 GHz with impedance matching ≤−10 dB. Both types of microwave sensors are designed on a flexible RO 3003 substrate and textile conductive fabric attached to a cotton substrate. The specific absorption rate (SAR) of the sensors is measured at different resonant frequencies on 1 g and 10 g of tissue, according to the IEEE C95.3 standard, and both sensors meet the standard limit of 1.6 W/kg and 2 W/kg, respectively. A simple peak-detection algorithm is used to demonstrate high accuracy in the detection of respiration, heartbeat, and lung water content. Based on the experimental results on a child and an adult volunteer, it can be concluded that UWB MASs offer superior performance when compared to NB sensors.