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In recent years, microwave filtering technologies have known great advancement and wide employment in wireless communication systems, necessitating the development of miniaturization techniques to respect the size limitation in wireless communication devices and reduce the cost, in order to satisfy the consumer and be more competitive. Accordingly, the design of a microwave filter is chosen based on its electrical performance, size, and manufacturing price. Therefore, it is necessary to make a good compromise between the mentioned criteria to satisfy the industrial requirements. This paper proposes a small and inexpensive bandpass filter (BPF), where the proposed structure is carefully constructed over a low-price FR4 Epoxy substrate with a full dimension of (17.6 × 9 × 1.6) mm3. The proposed filter offers good electrical performance in terms of reflection coefficient (S11), insertion loss (S21), Voltage Standing Wave Ratio (VSWR), and selectivity. A filter prototype is fabricated and tested to affirm the simulation results. Consequently, the measured results show a good agreement with the simulation, proving the suitability of the proposed filter for different wireless applications, including WLAN, Bluetooth, ZigBee, RFID, and ISM bands. [ABSTRACT FROM AUTHOR]

In this paper a wide-band, small size and high gain modified patch antenna array and a single element antenna for fifth Generation (5G) millimetre-wave (mm-wave) applications have been presented. The designing of single element antenna and array antenna is based on the Adaptive Neuro-Fuzzy Inference systems (ANFIS). The ANFIS technique is used to estimate the dimensions of the single element as well as the spacing between patch antenna elements in antenna array. The single element's operating frequency is 28 GHz, While the array antenna covers the frequency band from 23.6 to 29.2 GHz, resonating at 25 and 28 GHz. The antenna array was designed and simulated using the Rogers RT duroid 5880 Substrate, which has a dielectric constant of 2.2, a loss tangent tan (δ) of 0.0009, and thickness of 0.508 mm. The proposed single element patch antenna has a size of 4 × 4.8 × 0.508 mm 3 with wideband range from 23 to 38.6 GHz (15.6 GHz) with a gain of 4.17 dB. Based on these properties, the single element is expanded into a six-element array with a compact size of 13.2 × 23.8 × 0.508 mm 3 in order to enhance the gain and to make the antenna radiation pattern directional. The designed antenna array has a wide-band from 23.6 to 29.2GHz (5.6 GHz) and a high gain of 11 dB, making it as strong candidate for future mm-wave applications. [ABSTRACT FROM AUTHOR]

The MIMO antenna is one of the essential elements for the implementation of the new fifth-generation (5 G) technologies. The design of the MIMO antenna goes through several steps; the important one is the design of the single-element antenna that resonates at the desired frequency band(s). Its design becomes more difficult if it is a multi-band antenna. In addition, determining the dimensions of multi-band antennas by simulation or mathematical models is both more complicated, difficult, and time-consuming. In this research, different approaches based on artificial neural networks (ANN), radial basis function neural networks (RBFNN), and adaptive neuro-fuzzy inference systems (ANFIS) are used to predict the dimensions of a dual-band circular patch antenna with defected ground structure (DGS) for mm-wave 5 G applications, and then the performances of the three models are compared. To determine the training and the testing data, 280 antennas with different patch values and added slots in the ground plane are simulated. The resonant frequencies of the dual-band circular patch antenna and the height of the substrate are used as the input vector for the ANN, RBFNN, and ANFIS models. Two hundred twenty simulated antennas were used for training, and the remaining 60 data points were used to test the ANN, RBFNN, and ANFIS models. The performance of these models is compared in the training and testing process using some statistical criteria such as MSE, MAE, and RMSE. The proposed dual-band circular patch single-element antenna has a compact size of 5 × 6 × 0.8 m m 3 and exhibits good performance, such as broad band (3.8 and 3 GHz), high gain (6 and 7.1 dB), and high efficiency (99 % and 95 % ) in both operating bands. After studying the single-element antenna and in order to improve its performance, we proposed a 4 × 4 MIMO antenna with a total volume of 17 × 17 × 0.8 m m 3 that was designed by using four copies of the single-element antenna arranged orthogonally on the same low-loss Rogers Duroid 5880 substrate. The suggested 4 × 4 MIMO antenna achieves a high level of isolation (more than - 30 dB in both operating bands), which is obtained by inserting a cross-shaped decoupling structure among elements on the upper and lower sides of the substrate. Moreover, the proposed MIMO antenna has a good gain of 6.4 and 7.5 dB in both bands and a high radiation efficiency of 99.5 % and 99 % at 28 and 38 GHz, respectively. Furthermore, the diversity performance of the MIMO antenna is evaluated using a variety of crucial indicators, all of which greatly surpass realistic norms. The envelope correlation coefficient (ECC) is less than 0.005, the diversity gain (DG) is greater than 9.99 dB, the total active reflection coefficient (TARC) is below 10 dB, and the channel capacity loss (CCL) is no longer than 0.4 bits/s/Hz. In addition, the proposed dual band circular patch single element antenna and the 4 × 4 MIMO antenna are fabricated, and the measured results are in good agreement with the simulated results using HFSS and CST software. [ABSTRACT FROM AUTHOR]

In order to simplify the complex wireless communication system while maintaining good electrical performance and reducing the cost, a new compact design has been developed that combines two essential components of the wireless communication chain, the filter and the antenna, into a single multifunctional device capable of radiating and filtering. This filtering antenna, also known as a filtenna, was designed and manufactured for use in 5G sub-6 GHz and wireless applications at the n77-band (3.3–4.2 GHz). The structure consists of a hairpin filter made up of three folded U-shaped resonators integrated with a monopole antenna having a diamond-shaped radiating element. The strength of our work is that we were able to create a compact, small, and low-cost design while achieving good electrical performance. The simulated and measured results are compatible, the reflection coefficient showed a good impedance matching for both resonance frequencies 3.57 GHz and 4.10 GHz (|S11|≤ − 10 dB), as well as a voltage standing wave ratio less than 2. Several other results will be presented and discussed later in this article. The software used for the simulation is High-Frequency Structure Simulator (ANSYS HFSS) which employs the finite element approach. A prototype of the filtenna (filtering Antenna) was fabricated and measured using the vector network analyzer 3656D. [ABSTRACT FROM AUTHOR]

In this paper, we are interested to design a compact single band PIFA antenna using the artificial neural networks based on the multilayer perceptrons. The designed antenna will operate at the frequency 2.45 GHz for industrial, scientific and medical (ISM) band, the medical field, the mobile phone,the Wi-Fi and the Bluetooth. The absence of mathematical models that takes into account all the parameters that affect the characteristics of these antennas present a difficulty in the design of this type of antennas. In this paper, our main contribution is the development of a synthesis and analysis model for PIFA antenna based on the artificial neural network method. For this reasons, we have developed a model of the neural network based on the multilayer perceptron to predict the resonance frequency and the bandwidth of a single band PIFA antenna. By applying the same method, we managed to find a multilayer perceptron structure that can accurately predict the physicals dimensions of the PIFA single band antenna. Using the HFSS software, we designed the single band PIFA antenna that can operate at the frequency 2.45 GHz and presents a bandwidth at - 10 dB equal 1.0552 GHz, a good reflection coefficient ( - 51 dB), the gain is 6.5867 dB. [ABSTRACT FROM AUTHOR]

The millimeter-wave spectrum is deemed as an attractive solution to deal with the urgency of the high-data-rate needed to construct the 5G technology systems. Accordingly, this research work presents a high-isolation ultra-wideband dual-port MIMO antenna, and operates at the pioneer 28 GHz band for millimeter-wave 5G applications. The individual antenna consists of a new ring-shaped monopole antenna built on the low loss Rogers RT Duroid 5880 laminate, well-refined to bear a large bandwidth of 10 GHz from 24 to 34 GHz with suitable radiation features including a high radiation efficiency up to 99% and good comparable gain reaches to 5.9 dB. The single-antenna unit is carefully investigated, then exploited to propose a compact orthogonally placed two-port MIMO antenna with small total volume of 11 × 20.5 × 0.254mm3 while provides a strong isolation surpassing 25 dB. The MIMO diversity performance has been neatly evaluated in terms of various essential metrics, where an impressive performance has been proven. The simulation results are experimentally validated for both single and MIMO structures where a great harmony is demonstrated. Moreover, the impact of connected ground plane scheme on the MIMO antenna performance is also discussed, where a gratifying outcomes are accomplished. Besides, the proposed two-element MIMO antenna is further extended to four and eight elements MIMO antennas with connected ground plane configuration. A pretty simple decoupling structures are used, whereas a very satisfying results are fulfilled. The achieved outcomes make the proposed design superior to many existing designs and highly fit for the 5G wireless systems. [ABSTRACT FROM AUTHOR]

The current research offers a dual-band PIFA MIMO antenna (Multiple Input Multiple Output) with good isolation for mobile and wireless applications. The suggested antenna is designed by two steps; Firstly, uniform semi-patches with a dimension of 2.5 × 5 m m 2 are employed with the binary genetic algorithm (BGA) to obtain dual-band operation. Secondly, To enhance bandwidth and isolation, the real genetic algorithm (RGA) is applied to determine the dimension of the nonuniform overlaps. The suggested MIMO antenna covers the frequency bands 2.52 GHz up to 3.71 GHz and 5.2 GHz up to 5.95 GHz. The MIMO antenna exhibits strong isolation better than − 20dB in the two desired bands, according to the simulated S-parameters results. The MIMO parameters are simuated concerning the total active reflection coefficient (TARC), the envelope correlation coefficient (ECC), the diversity gain (DG), the gain, the efficiency, and the channel capacity loss (CCL). [ABSTRACT FROM AUTHOR]

The implementation of wireless technology at millimeter wave spectrum is becoming inevitable in the human life to keep pace with the urgent need of the high throughput and reliable transmission. In this research paper, a new miniaturized dual-wideband MIMO antenna has been suggested, and strictly studied for millimeter-wave 5G applications. The MIMO antenna is formed using four identical elements orthogonally placed on the low-loss RTRogers Duroid 5880 substrate with total area of 14 × 14 × 0.8mm3. Each element consists of an elliptical microstrip patch antenna with inset-feed and slotted ground plane, developed to provide dual band operation of 3 GHz (26.62–29.71 GHz) and 3.2 GHz (36.3–39.5 GHz) at the pioneer bands, namely 28 and 38 GHz respectively. The novelty of the suggested design resides in the inclusion of a new cross-shaped decoupling structure among elements in the upper and lower sides of the substrate to acquire severe isolation outstrips 30dB while retaining quite simple structure and very small size, besides desirable radiation traits, including high radiation efficiency exceeding 98%, reasonable gain up to 6.8 dB along with stable and directive patterns. Furthermore, the diversity performance of the MIMO antenna is also examined in terms of various essential metrics which are all significantly respected the agreed practical thresholds. The envelope correlation coefficient (ECC) is less than 0.0005, the diversity gain (DG) exceeds 9.99 dB, the total active reflection coefficient (TARC) is below − 10 dB, the channel capacity loss (CCL) is no longer than 0.35 bits/s/Hz and high channel capacity (CC) reaches to 22 bits/s/Hz. A detailed comparison with the existing works confirmed that the intended design blends several essential qualities that already mentioned which making it a sought-after option for 5G terminals. [ABSTRACT FROM AUTHOR]

Channel estimation (CE) is a crucial phase in wireless communication systems, especially in cell-free (CF) massive multiple input multiple output (M-MIMO) since it is a dynamic wireless network. Therefore, this work is introduced to study CE for the CF M-MIMO system in the uplink phase, wherein the performance of different estimators are evaluated, discussed, and compared in various situations. We assume the scenario in which each access point has prior knowledge of the channel statistics. The phase-aware-minimum mean square error (PA-MMSE) estimator, the non-phase-aware-MMSE (NPA-MMSE) estimator, and the least-squares estimator are the three estimators which are exploited in this work. Besides, we consider the Rician fading channel in which the line-of-sight path is realized with a phase-shift that models the users' mobility where the considered phase-shift follows a uniform distribution. On the other hand, the mean-squared error metric is employed in order to evaluate the performance of each estimator, where an analytical and simulated result is provided for the PA-MMSE estimator and the NPA-MMSE estimator in order to assert our numerical results. [ABSTRACT FROM AUTHOR]

A new compact pentagonal microstrip patch antenna with slotted ground plane structure, developed for use in ultrawideband applications, is studied in this article. The proposed antenna is mainly constituted by a pentagonal shaped patch antenna, a defected ground plane structure, two stubs, and four slots to improve the bandwidth. The designed antenna has an overall dimension of 30 × 17.59 × 1.6 mm3, for WIMAX/WLAN/WiFi/HIPERLAN-2 /Bluetooth/LTE/5G applications with a very large bandwidth starting from 2.66 to 10.82 GHz (S11 < − 6 dB). A parametric study of the ground plane structure was carried out to find the final and the optimal UWB antenna, and to confirm that the antenna has good performance and broader bandwidth. The proposed antenna prototype has been fabricated. The measured results indicate that the antenna has a good impedance matching. The antenna has an electrically small dimension with a good gain, a notable efficiency, and a wide impedance bandwidth, which makes this antenna an excellent candidate for ultrawideband wireless communication, microwave imaging, radar applications, and the major part of the mobile phone frequencies as well. [ABSTRACT FROM AUTHOR]

This manuscript presents a compact multi-band antenna with simple and small geometry dedicated to the millimeter-wave 5G wireless systems. The single antenna has been carefully designed on Rogers RT5880 laminate with a full dimension of 5 × 6 × 0.8 mm3 and studied using CST microwave studio software. A fabricated prototype has been made and tested to assess the simulation results where a very good agreement has been noted. The measurement revealed that the antenna covers the frequency bands of 23.99–24.187, 25.712–26.218 and 27.761–28.361 GHz resonating at 24.1, 26 and 28 GHz, where their corresponding gain are 6.4, 6.72 and 6.65 dB respectively. In addition, the antenna is featured with a stable radiation patterns and a maximum efficiency of 93%, which express high radiation performance. The antenna equivalent circuit has been also studied where the reflection coefficient achieved is in good accord with the simulated one. Furthermore, to fight the strong path loss at the mmWave spectrum, the single antenna element has been employed to propose a new three-dimensional phased array for 5G mobile phones using four edge-mounted subarrays each is composed of 10-elements and exhibits high gain of 16.1 dB. The subarrays altogether provide a robust coverage of 180° in both elevation and azimuth planes, while a full-coverage of 360° has been attained in the phi-plane using beamsteering technique. Besides, an extreme isolation greater than 50 dB is attained between the subarrays. The attained results prove that the proposed antenna could highly fit the 5G mobile phone applications. [ABSTRACT FROM AUTHOR]

This article presents a coplanar waveguide fed dual-band microstrip patch antenna for Wireless Local Area Network and Worldwide Interoperability for Microwave Access applications. The proposed antenna is designed using the artificial neural networks (ANN) method based on the multilayer perceptron structure; it is composed of a coplanar ground plane with a circular patch conductor printed on the FR4 dielectric substrate. The fabricated antenna configuration has a global dimension of 24 × 33.5 × 1.56 mm 3 . The proposed antenna presents numerous advantages like small size, low profile, and simple structure. The operation properties such as reflection coefficient, current distribution, radiation pattern, gain, and radiation efficiency are presented and discussed respectively using both ANSYS HFSS and CST MWS electromagnetic simulators. A dual band presenting three resonant frequencies is achieved by predicting the dimensions of the added slots in the radiating patch using the ANN technique. The measured − 10 dB impedance bandwidths are 390 MHz (2.17–2.56 GHz) centered at 2.46 GHz and 3670 MHz (2.82–6.49 GHz), which presents two resonant frequencies 3.73 GHz and 6.20 GHz, as the measured and the simulated results have a good agreement. Moreover, the designed antenna presents good radiation pattern over the operating bands. [ABSTRACT FROM AUTHOR]

In this study, we propose a new hybrid machine-learning algorithm called artificial multi-neural approach, for developing a multi-input single-output (MISO) model to estimate the hourly global solar radiation (HGSR) time series in Agdal site (latitude 31° 37′ N, longitude 08° 01′ W, elevation 466 m), Marrakesh, Morocco. To achieve this goal, three training algorithms (scaled conjugate gradient, Levenberg-Marquardt, and resilient backpropagation) are selected to train the developed model, using some accessible hourly meteorological variables recorded during 7 years (from 2008 to 2014) as exogenous inputs. Furthermore, a pertinence determination test (PDT) is used to point out the most pertinent inputs for the accurate HGSR estimation. The best configuration of the multi-neural model includes five known input parameters as the best scenario, i.e., acquisition hour, air temperature, relative humidity, wind speed, and precipitation. Some statistical indicators are used to evaluate the performance of the developed model. The obtained results demonstrate the reliability and the precision of our proposed machine-learning algorithm, representing a good solution for estimating solar radiation time series needed to design and manage solar energy systems compared to the present standards. [ABSTRACT FROM AUTHOR]