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A compact, tunable guided-mode resonant filter (GMRF) is experimentally demonstrated whose spectral reflectance wavelength varies as a function of the illumination position on the device. The GMRF consists of a grating of gradient-varying period ranging from 402.5 to 466.6 nm, which is obtained by casting a stretched polydimethylsiloxane (PDMS) grating wedge. By spatially changing the illumination position on the GMRF over 11 mm, a spectral reflectance peak with low sidelobes varies from 596.8 to 684.1 nm. The influence on the resonance efficiency and the limitation of the wavelength tuning range are discussed in depth. The GMRF is a good candidate as a functional filtering component in wavelength selection and sensing applications.

With the development of various wireless communication networks, Wi-Fi Router positioning and deployment systems have become widely popular in recent years to improve coverage in various environments. In this paper, we present an appropriate mechanism for defining the deployment of Wi-Fi Routers to improve coverage in the Oxford Languages Institute (OLI) environment. In addition, the institute's environment was simulated using the Wireless InSite (WI) Package. In this work, two types of Wi-Fi Routers are used. The first is the TP-Link, while the second is the Rocket. These two devices operate at 2.4 and 5 GHz frequencies. There are two objectives in this work. The first aim is to determine the best location to cover the simulated scene environment in a better way. The second aim is to compare Wi-Fi Routers to find out which Wi-Fi Router is better and find out how many Wi-Fi Routers we need to cover the institute's environment. The comparison between Wi-Fi Routers was based on basic parameters to measure the performance of wireless networks, the most important of which are Coverage Rate (CR) Percentage, Signal Quality Rate (SQR), and Received Power Rate (RPR). According to the results that were shown on the Graphical User Interface (GUI) using MATLAB Software. We noticed that the CR, SQR, and RPR of the Rocket are 83.9080%, 97.0082%, and -35.2337 dBm respectively, and these results are better than the results provided by the TP-Link, as it gave the CR, SQR, and RPR are 32.1839%, 77.8690%, and -58.1685 dBm, respectively. Finally, we conclude that CR using the Rocket is good and we need one device to cover the institute’s environment. While CR using the TP-Link is bad and we need five devices to reach the coverage provided by the Rocket because the Rocket has high transmitted power and gain capacity.

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This paper aims to implement a wireless Wi-Fi network (Indoor and Outdoor) in order to cover the environment of the Oxford Institute (to learn languages and computer skills) in the best methods and lowest cost in order to provide Wi-Fi service for faculty members and all members of the administrative board and students. The realistic three-floor indoor and outdoor environments of the Institute were designed with Wireless InSite Package (WIP). In addition, emphasis was focus on the use of two types of transmitting devices (Directional and Omni-Directional). The aim of using these two devices is to determine which device is better to cover the Institute's environment well. In this work, a different frequency bands scenario was used to determine which band is suitable for coverage and stability of the wireless network. These bands are S-Band (2.4GHz), C-Band (5GHz), C-Band (10GHz), Ku-Band (15GHz), Ka-Band (28GHz), and MmWave (39GHz). Moreover, the focus has been on the most important basic parameters to determine the performance level of the two devices (Directional and Omni-Directional) as well as to determine the performance level of the wireless network. The most important of these parameters are Path Losses (𝐿 𝑃𝑎𝑡ℎ ), Path Gain (𝐺 𝑃𝑎𝑡ℎ ), Received Signal Strength (RSS), Strongest Received Power, Coverage Ratio (CR), and Received Signal Quality Ratio (RSQR). According to the results that emerged, it was observed that Omni-Directional antennas are much better than Directional antennas, especially in NLOS (None-Line-of-Sight) regions. It was also noted that CR, 𝐿 𝑃𝑎𝑡ℎ , and RSS at S-Band (2.4GHz) are much better than the rest of the bands, so that the CR and the RSQR at this band reach 83.2184% and 95.7383%, respectively. While at the MmWave-Band (39GHz), it reaches 31.0345% and 70.7937% respectively.

In this paper, we present a new design for a multiple-input multiple-output (MIMO) antenna with four ports operating in wide and multi-millimeter-wave (Mm-Wave) bands for various 5G applications (including the internet of things (IoT), communication devices, and smartphones). The antenna is designed in a rectangular zigzag shape with slots to make the antenna operate at different frequencies. For this, the antenna operates at multiple frequencies from 38 to 62 GHz, so it supports all advanced wireless communication applications. The most important characteristic of the design is its small size and compact structure compared to designs presented by researchers in previous literature so<em> </em>the antenna dimensions for four elements are 29×49 mm². The antenna performance based on the results obtained from CST Studio Suite is good since the reflection coefficients of the antenna resonate at six main frequencies are 39.128 GHz, 42.992 GHz, 47.384 GHz, 51.536 GHz, 55.472 GHz, and 59.288 GHz. In addition, the isolation value between all antenna elements is ≤30 dB and the diversity gain value for all frequencies is 10 dB. Moreover, a very small value was obtained for the envelope correlation coefficient (ECC) is &lt;4.0576×10⁻¹¹. Finally, the results indicate a favorable design and potential competitor for all 5G MIMO Mm-Wave applications.<br /><em></em>

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