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This paper introduces a square slot antenna with circular polarization and dual-band capability. The structure of the antenna is similar to an L-shape patch but with modifications in the lower rectangular part of the L, the patch has been transformed into a circle. Additionally, two strips having rectangular shape are located on the ground plane at opposite corners. By adjusting the size of the rectangular strips, the antenna can achieve dual-band and dual-sense circular polarization. The measured results of this design indicate that the Impedance Bandwidths are 45.16% (2.4–3.8 GHz) and 43.75% (5–7.8 GHz), while the Axial Ratio Bandwidths are 45.16% (2.4–3.8 GHz) and 37.4% (5–7.3 GHz) for the lower and upper bands respectively. [ABSTRACT FROM AUTHOR]

This paper presents, a monopole rectangular patch antenna (0.57 × 0.52 × 0.035 λ3) featuring two horizontal slots and vertical rectangular slits, designed for single-band application. The analysis focuses on its suitability for single-band wireless communication applications. The proposed antenna resonates at frequency of 6.6 GHz and has a bandwidth of 500 MHz (from 6.38 to 6.88 GHz). The simulated results, including reflection coefficient, radiation pattern, gain, and surface current distribution, are presented in this paper. At the operating frequency of 6.6 GHz, the antenna achieves a gain of 3.24 dBi and a reflection coefficient of − 32.2 dB. The simulated and measured results of the proposed antenna are in good agreement, demonstrating its suitability for wireless communication applications. [ABSTRACT FROM AUTHOR]

This study focuses on improving data rates in wireless networks through the design, simulation and measurement of a frequency reconfigurable four port MIMO antenna. The antenna is specifically developed for Wi-Fi, wireless local area network, and Industrial, scientific and medical applications. The antenna design has microstrip patch components, a closely built decoupling structure, an electromagnetic band gap structure, and a defective ground structure. These features enhance the antenna's MIMO performance at specific frequencies of operation and minimize radiation losses. The antenna design includes an RF PIN diode to allow for reconfigurability. This enables the antenna to operate at resonating frequencies between 2.39 and 5.36 GHz while the diode is in the ON and OFF states, respectively. The MIMO antenna under consideration is assessed on a FR4 substrate of 70 × 65.5 mm 2 and the wavelength is 0.56 × 0.53 λ 0 . It achieves a peak gain of 7.3 dBi at 2.39 GHz and 8.2 dBi at 5.36 GHz. The simulated results are implemented using HFSS and measured using network analyser KEYSIGHT N9951A. The bandwidths achieved are 0.07 at 2.39 GHz and 0.53 at 5.36 GHz. The experimental results on analysing various antenna characteristics are observed as Total active reflection coefficient value less than 0 dB, envelope correlation coefficient less than 0.5, Mean effective gain value less than − 3 dB, etc. The gain of the proposed four port reconfigurable MIMO antenna is 10% improvement when compared with existing works. The results from the simulated and measured matches well within the two operating bands, indicating that the suggested topology could be used for 5G communications. [ABSTRACT FROM AUTHOR]

This paper presents folded cascode Low Noise Amplifier (LNA) designed for Wireless Local Area Network (WLAN) applications. The proposed LNA uses complementary current reuse technique and diode connected forward body biasing technique to lower the power consumption and boost the transconductance for gain enhancement. Moreover, post linearization is done by P-MOS (Metal Oxide Semiconductor) Inter Modulation Distortion (IMD) sinker which reduces inter modulation distortion present at the input and achieves better linearity of the LNA. Under cadence virtuoso environment, using 180 nm Complementary Metal Oxide Semiconductor (CMOS) technology, the designed LNA exhibit high gain (S21) of 25.4 dB followed by noise figure of 1.75 dB at a reduced supply voltage of 0.6 V. The other important parameters including reflection coefficient (S11) − 12 dB, power dissipation (Pdc) 3.23 mW and Third order Input Intercept Point (IIP3) − 4.43 dBm are also achieved. This demonstrates the applicability of proposed LNA for wireless applications functioning in 5.2 GHz. [ABSTRACT FROM AUTHOR]

In the present work, a metamaterial-inspired high gain multiband Circular Microstrip Antenna (CMSA) that facilitates operation at 2.4 , 3 , 5 , 7.1 , 8.45 , and 9.9 GHz for wireless communication is designed and illustrated. The antenna configuration consists of an array of crossed Complementary symmetry Split Ring Resonators (CSRR) as a metamaterial structure in the radiating patch that facilitates multiband operation and the meshed ground plane that facilitates high gain and bandwidth operations. A low-cost FR4 epoxy substrate with a thickness of 1.6 mm is used to fabricate the antenna. The overall structure is analyzed and validated using HFSS (High Frequency Structure Simulator). The simulated and measured results of the proposed antenna structure are in good agreement. The antenna attains a measured − 10 dB S 11 bandwidth 210 MHz with an improved gain of 3.48 dB and overall 90 % radiation efficiency at the desired resonating frequency of 2.45 GHz . The designed antenna offers appealing characteristics in the Industry Scientific and Medical (ISM) band and wireless communication applications for other operational bands like WLAN and Wi-MAX. [ABSTRACT FROM AUTHOR]

In this work, a dual-band dual circularly polarized coplanar waveguide (CPW)-fed monopole antenna is presented. The antenna consists of the modified ground plane, and two rectangular-shaped radiators, which are located on the two sides of the monopole. The radiating patches are loaded with metamaterial dependent electromagnetic band-gap structures for obtaining wider impedance bandwidth and broad axial ratio characteristics. The proposed antenna features impedance bandwidth of 97.4% (1–2.9 GHz) in the first band and 61.36% (3.05–5.75 GHz) in the second band, covering applications of ISM-band (2.4–2.48 GHz), Wi-MAX (2.5–2.69 GHz, 3.4–3.69 GHz), and WLAN (2.4–2.48 GHz, 5.15–5.35 GHz). The antenna also features dual circular polarization with 3-dB axial ratio bandwidth of 33.8% (1.35–1.9 GHz) and 35.7% (3.1–4.45 GHz), in the first and second bands, respectively. The first band shows right-hand circular polarization, whereas the second band exhibits left-hand circular polarization. [ABSTRACT FROM AUTHOR]

A miniature multiple input multiple output (MIMO) ultrawide band (UWB) antenna with dual band notched characteristics is proposed. The proposed MIMO UWB antenna has a microstrip feed line, two slotted rectangular radiating structures, and a slotted reduced ground structure. The antenna is constructed on an FR-4 substrate with a 40 × 20 mm2 compact dimension to span the − 10dB bandwidth of 2.5–12 GHz with a fractional bandwidth of 133%. The two notched bands for WiMAX (3.3–3.8 GHz) and WLAN (5–6.5 GHz), respectively, are generated using hook and E-structured stubs etched on patch and defective ground. Over the full operational frequency range, self-isolation of <-15 dB is obtained between two perpendicular radiating patch structures. 4-element MIMO antenna is also designed, studied and analysed. From the determined MIMO parameters, it can be concluded that the recommended antenna is adequate for portable wireless systems. [ABSTRACT FROM AUTHOR]

An antenna design with a coplanar waveguide (CPW) fed wide band circular polarization (CP), inspired by compact metamaterials, is presented in this paper. Substrate Integrated waveguide (SIW), metamaterial with CPW feed, and monopole patch make up its construction. A three-GHz axial ratio bandwidth (ARBW) is obtained by adding a rectangular slot at the monopole stub to produce CP. Incorporating SIW and metamaterial into the antenna design improves gain, directivity, bandwidth, and efficiency. Metamaterial and SIW utilized in the design comprising monopole patch with a stub, slots at the edges and the stub improve the antenna properties efficiently. ISM band, WLAN, and WBAN applications are appropriate for the suggested antenna. The antenna has a 3.6 dBi gain and measures 20 × 20 × 0.8 mm3. A radiation efficiency of 98% and a fractional bandwidth of 63.9% are obtained by incorporating the advantages of CP in a broadband SIW antenna inspired by metamaterials (3.99–7.62 GHz). [ABSTRACT FROM AUTHOR]

Communication through the wireless medium has a greater demand nowadays and it increases day by day due to the rapid increment of mobile users. Constantly, the antennas play a major role in the expanding wireless communication systems. Also, the demand increases for the smaller minimum-cost antenna for both industrial and domestic applications. The Inverted-F Antenna (IFA) designs support these requirements. This paper explains the study of the design of various band IFA forms for different applications like Bluetooth, WLAN, Wi-Fi and Zigbee. The design parameters and performance of different forms of IFAs are discussed and categorized in this paper. This review paper ultimately aims to highlight the Performance of IFA designs taken for analysis through gain comparison and return loss comparison for a fixed range of frequency. [ABSTRACT FROM AUTHOR]

The role of the antenna in wireless communication systems is to convert electromagnetic energy at radio frequency (RF) into electrical energy in the form of alternating current or vice versa. Antennas are different in design, appearance and specifications depending on how they will be used; gains, input impedance and radiation/sensitivity patterns may vary based on various parameters including operating frequencies. On the other hand, IEEE802.11 is the protocol established by the Institution of Electrical and Electronic Engineers (IEEE) to control and regulate wireless communications in computer local area networks (WLANs). In this protocol antennas are configured to work on a number of operating frequencies, such as 5 GHz, 6 GHz, 60 GHz and so on. IEEE 802.11 specifies the channels that can be used for WLANs, while the actual freedom to use the permitted RF spectra depends on the corresponding regulatory domains. This article presents a new functional prototype of WLAN microstrip fractal dual band antenna in accordance with IEEE802.11 standards. The suggested antenna features dual bands with two center frequencies located at 2.45 GHz and 5.8 GHz. The antenna is fabricated according to Minkowski pattern by using photoetching. In this research work, the characteristics of the antenna including its radiation/sensitivity pattern, scattering parameters, voltage standing wave ration (VSWR), input impedance, polarization, gain, bandwidth, and polarization are investigated, and hence the simulation and measurement results are acquired, examined, and contrasted with industry standards. [ABSTRACT FROM AUTHOR]

The present work suggests that high-speed cellular 5G sub-6 GHz and Wireless Local Area (WLAN) applications demand for a compact Multiple Input Multiple Output (MIMO) diversity antenna. N77, N78, and N79 are New Radio (NR) bands included in the 5G sub-6 GHz, as well as WLAN standards Wi-Fi 5 and Wi-Fi 6. The proposed MIMO diversity antenna is designed using low-cost FR4 dielectric material with a height of 1.6 mm. The FR4 material dimensions are 25 × 30 mm2 (0.258 × 0.310 λ02, λ0 is at working band lower frequency). The proposed MIMO diversity antenna achieves isolation of more than 18 dB over the whole working region and operates in the 3.12 to 7.12 GHz frequency range. High isolation characteristics are accomplished by properly optimizing the stub parameters that are placed between the antenna elements. The radiation performance metrics radiation efficiency, peak gain and field patterns are checked and analyzed. The radiation efficiency and peak gain values are greater than 95% and 2.6 dBi, respectively. The values of the diversity parameters Envelope Correlation Coefficient (ECC) (< 0.005), Diversity Gain (> 9.99 dB), Total Active Reflection coefficient (TARC) (< 10 dB), Channel Capacity Losses (< 0.05 bits/s/Hz), and Mean Effective Gain (< -– 3 dB) are simulated and compared with measured values. A good agreement is attained with all measured results when comparing with simulated ones. Based on the all the results, the proposed MIMO diversity antenna well suited for high speed cellular 5G applications and WLAN applications. [ABSTRACT FROM AUTHOR]

In this article, a high gain Circularly Polarized (CP) dual band 2 × 2 antenna array using sequential phase rotation technique for wireless applications is designed and investigated. The feed network utilizes four rectangular lines of equal width and three 90° arcs. The length of all elements is equal to λg/4 to provide 0°, 90°, 180° and 270° phase differences at the four outputs of feed network to increase Axial Ratio (AR) bandwidth and purity. Four corner truncated patch elements are connected to the feed network to complete 2 × 2 antenna array design. The proposed antenna array operates at two different frequency bands of 4.9–6 and 7.9–8.3 GHz (S11 < −10 dB) and also shows CP behavior at 5–5.8 and 8–8.4 GHz (AR < 3 dB) frequency bands. Very good similarity is attained between the axial ratio and impedance bandwidths. The maximum gain of the antenna array is 9.1 dB. The antenna array was prototyped and tested to validate its performance. This array is well suitable for WLAN, Wi-Fi and X-Band uplink satellite communication applications. [ABSTRACT FROM AUTHOR]

The use of miniaturized antennas in wireless communications is very common. In the current paper, a miniature coplanar-waveguide fed-rectangular patch antenna with semicircular ground is presented. The antenna performance was studied at two different configurations; straight and bent. Cross lines were added to ensure the obtained frequency band. Different parameters were evaluated including return-loss, radiation-pattern, gain and band-width. These parameters were analyzed numerically after twisting along both X and Y axis. Additionally, a prototype of the straight structured antenna is fabricated, and compared with the simulation results. The numerical results show high return loss (− 33 dB) at the straight structure, while the measured return loss decreased to − 28 dB. The bandwidth was 0.75-GHz in case of the straight structure and the measured bandwidth 0.18 GHz. The obtained gain at the resonance frequency is − 13 dB. Moreover, the proposed antenna resonates at frequency 3.22-GHz making it suitable for wireless communications, WIMAX and microwave S-band applications. [ABSTRACT FROM AUTHOR]

The design of an efficient frequency selective surface (FSS) array structure for a wearable antenna as a reflector is introduced in this paper. An ultra-wideband antenna capable of increasing the gain over Industrial, Scientific, and Medical (ISM) bands at 2.4 GHz and 5.8 GHz and reducing the Specific Absorption Rate (SAR) in the human body to be used for Wearable Body Area Network (WBAN) application is presented. Due to heavy data transmission for applications like wireless LAN, WiMAX, Bluetooth, and Zigbee, traffic at 2.4 GHz is getting congested. This has opened a new frequency in the ISM band at 5.8 GHz. The proposed antenna structure includes a circular patch with semi-circular and diamond-shaped slots which is fabricated on textile material. Flannel fabric is chosen as a substrate. The slots introduced in the circular patch antenna aim in obtaining impedance bandwidth of 4.5 GHz from 1.5–6 GHz covering ISM bands with optimal results at 2.4 GHz and 5.8 GHz. FSS structure is used as a reflector to enhance and stabilize the gain throughout the wideband. Thus, the proposed antenna has a wideband and Omni-directional pattern making it useful for WBAN. The designed FSS structure reduces the SAR value to 0.56 W/kg and 0.511 W/kg at 2.4 GHz and 5.8 GHz respectively. The gain is 3.4 dBi at 2.4 GHz and 3.35 dBi at 5.8 GHz when the FSS reflector is placed at 1 mm below the antenna. The overall dimension of the antenna with reflector setup is 42 × 43 × 3 mm3 which is 0.7λ wavelengths making it feasible to be worn on the human body. [ABSTRACT FROM AUTHOR]

This paper presents a dual band microstrip antenna (MSA) of compact planner size 39 mm×47.6 mm (0.21 × 0.25 λ 0 2 at lowest resonant frequency 1.60 GHz) loaded with two T-shape notches. The notches loaded patch antenna provides dual band characteristics from 1.55 to 1.66 GHz (lower band) while 2.13 to 3.32 GHz (upper band). The proposed dual band antenna exhibits impedance bandwidth of 6.95% (110 MHz) with − 16.02 dB reflection coefficient at 1.60 GHz in lower band while 43.67% (1190 MHz) with − 19.57 dB reflection coefficient at 2.30 GHz and − 38.97 dB reflection coefficient at 2.95 GHz in upper band. The antenna shows stable peak gain of 3.42 dB in lower band at 1.60 GHz while 4.03 and 3.45 dB in upper band at 2.30 and 2.95 GHz respectively. The radiation efficiency of 86–93.5% and 86–96% is achieved in lower and upper resonating band respectively. The proposed antenna is designed with FR-4 substrate and simulated by IE3D software. The excitation of proposed antenna has been done with microstrip line feed (50Ω). The resonating frequency band can be used for GPS, WLAN and WiMAX applications in wireless communication. [ABSTRACT FROM AUTHOR]

Wireless communication's significance has grown as a result of its widespread use, and with the passage of time, new developing technologies have expanded their function as well. Wireless technology has advanced considerably during the last two decades and has become an essential element of human existence. IEEE-802.11 is the most widely used and mature standard for wireless communication inside local area networks. IEEE-802.11 standard updates are often required as a consequence of emerging technologies and the need for new, error-prone, and rapid connections. The purpose of this research is to provide the findings of a systematic assessment conducted using reports, IEEE-802.11 standard documents, and peer-reviewed publications. We detailed what advancements have been achieved to date and the constraints that drove these advancements in the area of WLANs. [ABSTRACT FROM AUTHOR]

Microstrip antenna technology has gained significant momentum in recent times, finding widespread applications in mobile and satellite communications. These antennas offer advantages such as cost-effectiveness, low profile, and easy fabrication. However, one of the limitations of microstrip antennas is their limited bandwidth utilization. To address this drawback, a proposed methodology has been introduced to enhance the bandwidth utilization factor and overcome this limitation. The proposed method involves the design of a microstrip rectangular patch antenna using co-planar parasitic rod elements and substrate integrating feeding line technique. This approach aims to improve various aspects of the antenna's performance, including bandwidth enhancement, front-to-back ratio improvement, loss reduction, increased quality factor, and higher power handling capability. Through the proposed method, the bandwidth ratio is significantly increased from 4 to 18%, demonstrating superior results compared to existing approaches. The simulation and 3D plot results were obtained using Ansoft HFSS (High-Frequency Structure Simulator) software, confirming the effectiveness of the proposed methodology in achieving efficient bandwidth utilization and overall antenna performance improvements. [ABSTRACT FROM AUTHOR]

In this article, a simple design of a stacked patch dual band circular polarized antenna is designed and tested that can be used for GPS L1 (1575.42 MHz) and L2 (1227.6 MHz) applications. The lower patch is designed for L2 band, and the upper patch is designed for L1 band. Circular polarization in the upper patch is achieved by inculcation of corner truncation, and in lower patch it is achieved by inclusion of both corner truncation and an I-slot. A peak gain of 5.5 and 4.5 dBic is achieved at L1 and L2 bands with a broad beam required for GPS applications. It exhibits a minimal axial ratio of 0.6 dB. The fabricated prototype is experimented. In addition, a parametric analysis was performed to study the impact of antenna performance due to various geometrical parameters. [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]

The design of a compact array antenna of four pentagon microstrip patch antenna (PMSPA) has been proposed for sub 6 GHz applications. This array is to be achieved broadband (BB) and enhance directivity. The advantages of this proposed array are long-distance communication without attenuation of signals (i.e., enhancement of signal-to-noise ratio(SNR)) and enhance the channel capacity. An analysis of a proposed four elements array is designed with a corporate feed network on a substrate of FR4 epoxy of a dielectric constant of 4.4 with a thickness of 1.6 mm at 6 GHz, which is simulated and analyzed in the results in HFSS software. The final model after analysis of the results is fabricated and its experimental results are compared with the simulation results. Both the fabricated and simulated results have almost the same other. its broadband is from 3.67 GHz to 5.05 GHz (i.e., the bandwidth of 1.48 GHz), and a maximum of 12.93 dB of directivity between 3 and 6 GHz. This proposed four-element pentagon microstrip patch antenna array is covered n77 and n78 bands for 5G wireless communication systems mainly. [ABSTRACT FROM AUTHOR]

Beamforming is one of the vibrant emerging techniques for the next generation of wireless communication. It has many applications including localization of objects in indoor and outdoor environment, radar, D2D communication, vehicular networks, astronomy, and biomedical instruments. The main requirements of beamforming are the antenna with narrow beamwidth and a network for steering the beam in the desired direction. In this paper, a Quad-element microstrip array antenna with H-type feeding and corporate feeding are proposed as beamforming antennas to locate the user equipment in indoor WiFi, and WLAN environment. The performance metrics such as, voltage standing wave ratio (VSWR), return loss and gain are also evaluated for the variety of arrangement of array elements with the single element microstrip antenna. The test result shows that the proposed array antenna provides unidirectional at 2.26 and 6.35 GHz. It measures a VSWR of less than 2 dB which is desirable. Moreover, it gives a return loss of −12.63 dB at 6.54 GHz and −16.21 dB at 6.63 GHz. It shows that designed antenna is suitable for beamforming for user equipment localization at indoor environment. [ABSTRACT FROM AUTHOR]

In this work, a Coaxial fed 2 × 2 array antenna is proposed. This antenna employsfour patch elements, and the individual feedlines are connected to a standard coaxial feed. The size of the antenna is 74.4 × 74.4 mm 2 with a substrate thickness of 1.6 mm. Polyamide is used as a substrate which has a dielectric constant of 4.3. The antenna's operating band starts from 4.05 to 4.32 GHz, with a bandwidth of 0.27 GHz and a resonating frequency of 4.2 GHz and 5.2 GHz. The proposed antenna achieved a peak gain of 9.1 dB and a radiation efficiency of 85%. The design and simulations of the antenna were made using HFSS software. This antenna works for receiving band of standard c-band and as radio altimeters. [ABSTRACT FROM AUTHOR]

In the paper, a UWB-MIMO antenna with quintuple notched-band ability is proposed. Four CCSRR slots and a couple of C-like stub are engraved to avoid five frequency bands at 3.4–4 GHz, 5.2–5.7 GHz, 5.9–6.3 GHz, 7.5–7.9 GHz and 8.3–8.9 GHz. Thus the system has refusal ability at WiMAX, lower WLAN, upper WLAN, low side band of X-band and upside band of X-band. Mutual coupling was suppressed and the isolation was more than 20 dB by means of three decoupling methods(cutting a triangular shape on upper patch, etching a ground slot and adding a candied haws shaped stub). The entire UWB-MIMO antenna has a smart size of 30 × 44 mm2 and works in 3–11 GHz band. Design principles, parameter analysis are further studied. The result data of S-parameters, far-field E-plane and H-plane patterns, ECC, DG, gain, and efficiency indicate that the proposed antenna is a satisfactory candidate in practical use of UWB. [ABSTRACT FROM AUTHOR]

This work, presents the design and realization of two new miniaturized circular antennas as well as their effects on the human body. The first step consists in simulation each bi-band antenna at 2.5 GHz and at 5.2 GHz for wireless applications using the simulators HFSS and CST Microwave studio. The second step is manifested by the type of permeability substrates, the modifications of the radiating element and the ground plane as well as the modification of the feeding technique. All these miniaturization methods were used to limit the peak of specific absorption rate (SAR) in the human body. The SAR is calculated on a 1 and 10 g tissue mass respectively. The performed tests show that the SAR rate, which affects the human body tissues and obtained by the antenna with a full ground plane, is lower than that provided by the antenna with a truncated ground plane. Furthermore, the SAR rate observed in the different frequency bands for the antenna 2 complies with the standards proposed by the international commission on non-ionizing radiation protection. [ABSTRACT FROM AUTHOR]

This paper proposes an algorithm for the dynamic assignment of Restricted Access Window (RAW) for IEEE 802.11 ah. The Internet of Things (IoT) has groups of sensors and stations interacting over a common network. Wireless Local Area Network (WLAN) standard IEEE 802.11ah is best for IoT because it has high data rate and wide coverage while consuming low power. IEEE 802.11ah uses cautiously selected fixed RAW through an Access Point (AP), so that the chances of packet collision is minimized and energy efficiency is improved. By keeping it static, however, the effectiveness of RAW to utilize channels is reduced. We are suggesting an algorithm in which AP roughly calculates network packet transmission and the number of transmitting stations, and assigns resources to IoT networks by modifying RAW dynamically. The proposed algorithm shows improvement in average delay, throughput, PDR and jitter. The proposed algorithm achieves one of the best performances with an average delay of 0.43 sec, throughput of about 23 kbps, maximum packet delivery ratio (PDR) of about 98%, and jitter of about 80 sec. [ABSTRACT FROM AUTHOR]

An innovative magnetodielectric nanocomposite antenna is proposed for enhancing antenna parameters of monopole radiator by coplanar waveguide (CPW) feeding. A magnetodielectric nanocomposite radiator works in triband that covers the frequency band in WLAN, WiMAX and 5G. This compact antenna incorporates three radiating elements, whose total width is only 35% width of signal strip and length of the longer monopole is only 0.18 wavelength at its resonance frequency. To obtain a good impedance bandwidth for the triple band operation, two narrow rectangular patches (4 × 2 mm2, 4.5 × 1.5 mm2) are embedded in the two radiating elements of antenna. Carbon-coated cobalt (CCo) in coalesce with polyaniline (PANI) results in a magnetodielectric polymer-based nanocomposite. To enhance the antenna parameter the 'L' shaped slot upright to CPW ground, which is filled with PANI/CCo magnetodielectric nanocomposite. The resulting antenna produce good 10-dB impedance bandwidth of 0.43 GHz (2.30–2.73 GHz), 0.41 GHz (3.35–3.76 GHz) and 0.94 GHz (5.02–5.96 GHz) for entire WLAN/WiMAX bands are covered, 2.3–2.4 GHz inclusively 2.5–2.69 GHz 5G bands and 82% band width of 3.3–3.8 GHz 5G band are also included along with good radiation characteristics for entire triple band. [ABSTRACT FROM AUTHOR]

A compact ( 17 × 10 mm 2 ) microstrip patch antenna design has been proposed in this correspondence. This design achieves triple band notch characteristics with circular polarization. The proposed design consists of semi-circular radiating patch and defected ground structure to cover the bandwidths for C/X/Ku/K-band applications. Defected ground is created by the introduction of slot, slit, and copper connecting strip on the ground plane. The triple band notches covering impedance bandwidth 4.94 GHz (4.96–9.9 GHz), 3.6 GHz (11.0–14.6 GHz), and 3.8 GHz (16.20–20 GHz), are obtained for the proposed design. Moreover, this antenna exhibits axial ratio bandwidth ≤ 3 dB. The proposed antenna resonates in triple band at resonant frequencies of 5.5, 12.4 and 17.3 GHz. Furthermore, the proposed microstrip patch antenna design has been fabricated and the simulation results (obtained by HFSS software) are corroborated by the measured results obtained by vector network analyzer using the fabricated antenna. [ABSTRACT FROM AUTHOR]

In this article, a dual band frequency reconfigurable antenna is proposed for WiMAX and WLAN applications. Double-Square-Ring (DSR) shaped radiator is designed to exhibit dual mode operations and PIN diodes are implemented to switch the operating modes. Coaxial feed is selected to feed the antenna as the spurious radiation from it is minimal as compared with the microstrip feed. The current path along the radiating patch is affected with the ON and OFF conditions of the PIN diode which results in dual mode operation of the proposed antenna. The antenna is having a small footprint of 40 × 40 mm2 fabricated on a 1.6 mm thick FR-4 substrate. Presented antenna covers an impedance bandwidth of 52 MHz in WiMAX band (2.28 − 2.33 GHz) and 157 MHz in the WLAN band (5.1 − 5.28 GHz). This antenna's working principle is explained through current distribution diagrams along with design evolution. The experimental and simulated results are presented to validate the proposed antenna design. [ABSTRACT FROM AUTHOR]

The design of low profile Koch fractal (KF) antenna is proposed for broadband public safety applications. The radiating element of the proposed antenna is constructed by engraving KF geometry. Square complementary split ring resonator (SCSRR) is loaded in the ground plane for achieving dual band operation. The proposed SCSRR loaded KF antenna is fabricated by using flexible Poly vinyl chloride material. Furthermore, the experimental validations of the antenna parameters are carried out with the help of an anechoic chamber that is associated with vector network analyser. Results show that the proposed KF antenna operates at the frequencies of 4914 MHz and 5407 MHz. The achieved bandwidths are 382 MHz for the first band and 402 MHz for the second band respectively. The footprint of the antenna is 20 × 20 × 0.8 mm3 and the designed antenna can support broadband public safety and WLAN applications. [ABSTRACT FROM AUTHOR]

A co-planar waveguide (CPW)-fed dual-band circularly-polarized (CP) disc-shaped monopole antenna with an electromagnetic band gap (EBG) array is presented for Wi-MAX, WLAN, and ISM band applications. The proposed monopole antenna is comprised of an arc-shaped stub (in the middle), a C-shaped strip (on the left), and an inverted L-shaped strip (in the right). The circular polarization is produced by truncating an arc in the T-shaped radiator, and the antenna is placed over an EBG array to achieve broader impedance and axial ratio bandwidths. The impedance bandwidth and axial ratio bandwidth (ARBW) in the first resonating band are 36.73% (2–2.9 GHz) and 21.16% (2.24–2.77 GHz), respectively. The antenna covers (2.4–2.48 GHz) WLAN/ISM band, (2.5–2.69 GHz) Wi-MAX band, and (2.38–2.49 GHz) Bluetooth application. The impedance bandwidth in the second resonating band is 6% (5.65–6 GHz), which covers (5.72–5.87 GHz) ISM band and (5.72–5.85 GHz) WLAN band. The CPW-fed disc-shaped antenna with an EBG array has dual band radiation characteristics, improved gain and radiation efficiency, compact size, and simple, light weight, and easy design with no vias required. The radiation characteristics of the proposed antenna are measured, and they agree well with the simulated results. [ABSTRACT FROM AUTHOR]

This research article describes the design of a circular-shaped microstrip patch antenna in detail. The circular shaped microstrip antenna is designed to resonate at 10 frequency bands from 3.2 to 19.1 GHz and hence it can be used for advance wireless communication applications. The designed antenna can be used in small handheld devices supporting communication protocols like Bluetooth 2.0, Bluetooth Low Energy, Wireless Fidelity (Wi-Fi), Zigbee IEEE 802.15. 4, 2G/3G/4G/LTE-A, and 5G. The designed antenna can resonate at 10 different frequencies from 3.2 to 19.1 GHz (3.2, 5.3, 7.4, 9.6, 11.7, 13.2, 13.2, 13.7, 15.3, and 19.1 GHz). The bands of frequencies are specifically designed frequencies on which the designed circular-shaped microstrip patch antenna would work and can be modified and redesigned to work for a different dedicated application/protocol operating between the ranges of 3.2–19.10 GHz. At 10 different frequencies specified here, the observed values of S-parameter are lower than − 10 dB. The voltage standing wave ratios of the antenna at above frequencies are in between 1 and 2. As the antenna shows narrow band communication capabilities at these frequencies, the antenna can be used for a definite purpose with a definite frequency with no interference with other wireless communication system. [ABSTRACT FROM AUTHOR]

Over the last few years there has been explosive growth in the use of the Wireless communications from top to bottom i.e. Satellite transmission to home Wireless personal area networks. The primary advantage of a wireless network is the ability of wireless node to communicate with the universe during mobility. Two basic system models of a wireless system are fixed and Mobile Adhoc Network has been developed for the wireless network paradigm. The first model consists of multiple numbers of mobile workstations and relatively fewer but more powerful, having fixed routers. The second model has been proposed to set up a network on-demand basis. When a collection of wireless mobile nodes are capable of communicating with each other without the use of network infrastructure, centralized administration, or centralized control like mobile switching centers or base stations, that set up is called Mobile Adhoc Network. Here each mobile node operates not only as a host but also as a router, forwards packets to other mobile nodes in the network that may not be within direct wireless transmission range of each other. Each node participates in an Adhoc routing protocol (Yadav et al. in Comput Netw 118:15–23, 2017) that allows it to discover multiple paths through the network to any other node. Institute of Electrical and Electronics Engineers 802.11 (IEEE 802.11) [Kaur et al. in Int J Res Advent Technol 5(8), 2017] is a vital part of pervasive networks, which is a special kind of network where users can join and communicate anytime or anywhere on the fly. It is a popular kind of network because its applications cover a variety of areas. A unique communication paradigm is used which is able to run without fixed infrastructure and relies on wireless terminals for routing and transporting services. A number of security and scalability issues arise due to its wireless transmissions and unpredictable topology changes. Open standard, dynamic topology, scattered arrangements, and multi-hop routing are crucial features of IEEE 802.11 networks that make them vulnerable to various kinds of attacks. A Wormhole attack is one of the serious kinds of attack. Thus, security is the most important concern in IEEE 802.11 networks. This paper presents the refurbishment of the routing structure of Ad hoc On-Demand Distance Vectors (AODV) protocol (Ning et al. in Proceedings of the IEEE systems, man and cybernetics society information assurance workshop (IAW), West Point, New York, USA, pp 60–67, 2003). It will be helpful to safeguard IEEE 802.11 networks from Wormhole attacks by preventing Wormhole Attacks. The DAPS technique had been presented in Saini et al. (Int J Res Advent Technol 6(4), 2018) to detect Wormhole Attacks. Further to DAPS technique, a new Wormhole prevention technique has been introduced in this paper called Proactive Prevention Key Solution (PPKS). [ABSTRACT FROM AUTHOR]

This communication reports a frequency reconfigurable wearable low-cost multi band antenna using diode integrated metamaterial switching combination. The antenna covers the frequency spectra of WLAN, WiMAX and GSM application bands. The antenna is designed and fabricated on a jean's material which is characterized by using vector network analyzer and dielectric assessment kit. Two Split Ring Resonator (SRR) metamaterial structures are placed in proximity to the feed line for stopping the two different resonant bands in a particular instant. The antenna covers the frequency ranges from 1.54 to 2.45 GHz, 2.95 to 3.4 GHz, 4.58 to 5.05 GHz and 5.29 to 6.34 GHz when both the diodes are in off condition. For on condition of the diodes, the proposed antenna covers the frequency spectra from 1.6 to 2.8 GHz and 5.1 to 6 GHz. The wearable antenna design is analyzed on a human body model and bending conditions but the antenna has more SAR value. To further reduced the SAR, a periodic rectangular structure is used below the ground layer which reflects the radiation in the upper direction. The measurements and simulated result have shown good agreement between them. [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]

Design of a textile antenna operating at multi frequency band with microstrip patched is proposed in this paper significant for applications operating at 5G and LTE band. The design involves a U-Shaped slot, a rectangular shaped microstrip patched and two annular concentric slots. Current distribution in the surface undergoes modification by introducing three meanders sleeved in the ground plane leading to improvement of bandwidth. Coral Reefs Optimization integrated with Substrate Layer (CRO-SL) algorithm is utilized for optimizing the meanders, the dual circular slots and the U-shaped slot. The multi optimization method is utilized for this meta-heuristic population based approach which is a type of ensemble algorithm which considers various search operators in the same algorithm. In this work, a robust textile antenna is optimized using CRO-SL algorithm which operates at the frequency band of both LTE and 5G range. The process of optimization precedes by a fitness function guiding the CRO-SL, generated by means of antenna simulation through hybridizing with CST simulation software such that electromagnetic analysis is performed in the high frequency range. [ABSTRACT FROM AUTHOR]

The use of channels in WLANs affects data communication. RTS Fragmentation Threshold (RTSFT), Fragmentation Threshold (FT), and Buffer Size (BS) input values; Receiver Channel Utilization% (RCU%) and Transmitter Channel Utilization% (TCU%) affect the output values. To use the communication channel most efficiently, RTSFT, FT, and BS input variable values, which give the best RCU% and TCU% values, were obtained using the Riverbed Modeler simulation tool. Bandwidth, which is an important parameter for increasing the QoS of Wireless Local Area Networks, provides only physical performance efficiency. The efficiency at which the bandwidth is used is extremely important for the pre-design of network topology. The channel utilization rate increases the efficient use of bandwidth in WLANs. RTSFT, FT, and BS, which affect the service quality in the MAC layer in WLANs, directly affect the quality of service. In this study, the Prediction of Receiver Channel Utilization% (RCU%) and Prediction of Transmitter Channel Utilization% (TCU%) performance criteria were predicted by using ANN algorithms. Using the Riverbed Modeler simulation tool, 125 different input variables with 11 nodes were selected and channel utilization was obtained. Used ANN data was obtained from real Riverbed Modeler simulation. Input variables (RTSFT, FT, and BS) against the output parameters (RCU% and TCU%) were obtained from ANN model prediction. It is concluded that the estimated RCU% and TCU% output values are revealed the affected directly proportional by the BS input and inversely proportional to the RTSFT and FT input values. [ABSTRACT FROM AUTHOR]

In this paper, a minimized dual-band multiple input multiple output (MIMO) antenna with high isolation is presented for the fifth generation (5G) and the wireless local area network (WLAN) applications. The proposed antenna structure is composed of two adjacent identical antenna elements which are fed through microstrip lines. The isolation is improved by using a modified T-shaped structure with the defected ground structure (DGS). Finally, the antenna prototype is fabricated and measured. The measured S11 < − 10 dB impedance bandwidth is obtained in 3.3–3.9 GHz and 4.6–5.5 GHz frequency bands, which can cover 5G New Radio N78 (3.3–3.8 GHz) and WLAN (5.15–5.35 GHz). The measured isolation is better than 15 dB, the measured efficiency is larger than 40% and the ECC is smaller than 0.1 in both operating frequency bands. Therefore, the proposed antenna is feasible to be used for 5G and WLAN applications. [ABSTRACT FROM AUTHOR]

In this research work, the authors have presented the design of a compact flexible wearable fractal patch antenna used for body area networks (BAN) applications in the 2.45 GHz ISM band. For the size miniaturization of the antenna the crown fractal patch antenna geometry has been used. Five flexible substrate materials namely denim, polythene foam, cotton cloth, felt and fleece have been analysed as the substrates of the antenna and the antenna size miniaturization ranging from 24.1 to 29.7% has been achieved. The denim substrate based antenna occupies the minimum area as compared to that of all the other four designed antennas; hence, the denim substrate based antenna has been fabricated and experimentally tested. The measured parameters of the antenna show good agreement with the simulated values. The proposed fabricated denim substrate based antenna has also been analyzed for bending effect evaluation and it has been found that the horizontal and vertical bending up to the bending radius of 45 mm of the antenna does not significantly affect the performance of the antenna. The equivalent circuit analysis of the proposed antenna has been presented and the theoretical, simulated, and experimental results have been found in good agreement. [ABSTRACT FROM AUTHOR]

This article proposed a compact dual-element MIMO (multiple-input-multiple-output) antenna system working in 1.575 GHz (Global Positioning System)/4.5 GHz (5G)/5.8 GHz (Wireless Local Area Network)/6.4 GHz (Satellite communication) with relatively high isolation. The proposed antenna element consists of compact inverted-F antenna with meandered arm. One side of the T-shaped monopole antenna is extended and meandered while the other side is grounded to form the IFA structure. Meandering of the arm is responsible for the quad-band response. The proposed structure is simulated and fabricated on a FR4 substrate with an overall dimension of (0.23 λ0 × 0.09 λ0 × 0.004 λ0) and edge-to-edge separation of the two patches is 0.04 λ0, where λ0 is the wavelength at lower resonating frequency (1.575 GHz) of the proposed antenna. The high isolation is achieved by incorporating two inverted L-shaped strips and a narrow slot in the ground plane. Envelope correlation co-efficient (ECC) and channel capacity loss (CCL) are within their acceptable limits. Other different diversity parameters are evaluated and the results are satisfactory for MIMO applications. [ABSTRACT FROM AUTHOR]

Multi Input Multi Output (MIMO) and phased array systems are considered a key technologies to realize the 5G communication systems. Therefore, the purpose of this research is the suggestion of a novel mm-wave Ultrawide Band (UWB) antenna design with compact and straightforward layout suitable for both MIMO and phased array systems. Hence, the designed antenna array has been studied separately as a MIMO antenna and as a phased array antenna to carefully assess the performance of each system. The single antenna design is an elliptical patch antenna where the design novelty lies in the combination of a modified inset-feed and defected ground structure to provide a large bandwidth without any compromise in the radiation performance, nor in antenna size and design simplicity. The Design process are performed using CST MWS software, where the Rogers RT/Duroid 5880 substrate is chosen to construct the antenna. A broadband characteristic of 8.7 GHz from 26 to 34.7 GHz with two resonant frequencies at 28 GHz and 33 GHz is obtained. A good radiation properties are achieved, where the gain is greater than 4.5 dB while the radiation efficiency exceeds 97% over the operating band. The MIMO and phased array antennas are made up of 12-elements of the single UWB-antenna arranged linearly along the width-edge of the smartphone mainboard. The MIMO antenna proves a high diversity performance in terms of Diversity Gain (DG), Envelope Correlation Coefficient (ECC), Total Active Reflection Coefficient (TARC), Channel Capacity Loss (CCL) and Mean Effective Gain (MEG), owing to the low mutual coupling less than − 20 dB, which is obtained using a separating slits between the elements. In addition, the suggested phased array provides a highly stable gain up to 15 dB over the entire bandwidth at broadside direction, besides the wide scanning range of ± 60° at 28 GHz and ± 40° at 33 GHz. Hence, the attained results assure that the suggested antenna could be appropriate for incorporation in 5G smartphones and other wireless devices and can be effectively used for both phased array and MIMO applications. [ABSTRACT FROM AUTHOR]

In this paper, a novel compact semi-circular slot (SCS) 2 × 2 MIMO antenna is presented for 5G NR sub-6 GHz applications with high isolation. The proposed antenna consists of a semi-circular slot in ground plane, U-shaped stub, and 50-ohm microstrip feed line. The novelty of this paper are the Semi-Circular Slot acts a radiator, the port isolation is enhanced using a simple conductor strip as a neutralization line, very compact in size, low ECC, and good impedance matching. The overall size of the proposed SCS MIMO antenna is 16 mm x 21 mm, and FR4 substrate is used with thickness of 1.6 mm. The two SCS antenna elements are separated by edge-to-edge distance of 1mm ( = 0.019 λ 0 ). The proposed compact MIMO antenna design is simulated using Ansys HFSS. To validate SCS MIMO antenna, a prototype was fabricated and tested. The measured results are attained at 5.5 GHz with isolation greater than 25dB, impedance bandwidth (S11 < - 10 dB) covers from 5.10 GHz to 5.80 GHz with return loss of − 39.5 dB. The MIMO antenna parameters, ECC, CCL, TARC, and MEG are studied, and the values are obtained within acceptable limits. The measured and simulated antenna results are almost similar. This compact MIMO antenna is suitable for 5G communications in sub-6 GHz wifi-5 band applications. [ABSTRACT FROM AUTHOR]

A novel low profile ultra-wideband antenna design has been presented in this work, that offers switchable band-notch characteristics suitable for both wideband and narrowband applications. The ultra-wideband characteristics (3.1–10.6 GHz) have been accomplished by using a unique elliptical shaped radiating structure, which is fed by a 50 Ω rectangular feedline and incorporating a defected ground structure that encompasses a pair of L-shaped slots and two rectangular slots for enhancing impedance matching performance. The proposed design has offered four notch-bands (Wi-Max, WLAN, X-band and C-band) that have been attained by using combinations of various types of slot structures in distinct parts of the proposed design along with a pair of split ring resonators. The reconfigurability among the desired notch-bands have been realized by configuring five switches in their ON/OFF states, which has resulted in a design apt for various narrowband applications. Antenna design optimization and performance evaluation has been carried out with the help of HFSSv13 tool. The performance of antenna has been assessed in terms of VSWR, gain and radiation patterns. The simulated and measured results have validated that antenna exhibits an operational UWB bandwidth from 3.1 to 10.6 GHz (with VSRW < 2) encompassing four notch-bands at 3.1–3.65 GHz (Wi-Max), 4.9–5.56 GHz (WLAN), 5.9–6.4 GHz (C-UPLINK) and 7.3–8.5 GHz (X-UPLINK). The profile size of the presented antenna (24 × 24 × 1.6 mm3) is appreciably compact and displays a fairly stable gain and radiation pattern characteristics for complete operational bandwidth except for four switchable notch-bands, making it suitable for wideband and narrowband applications. [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]

This article presents a compact antenna design of overall size 38.4 mm × 46.8 mm having square shape and an inverted F-shape notches. The proposed antenna of single band is resonating between 1.69 and 2.91 GHz at two frequencies 1.98 GHz and 2.56 GHz. The proposed structure of antenna design has three square shape notches at corner and an inverted F-shape notch. The loading of notches inside radiating patch increases the effective current path. Due to increase of current path, radiation of antenna increases and large bandwidth is obtained. The reflection coefficient and impedance bandwidth both are increases gradually by loading different notches in radiating patch. Parametric investigation is also performed to figure out the effect of different parameters. The proposed antenna shows fractional bandwidth of 53.04% (1220 MHz) resonating at frequencies 1.98 GHz and 2.56 GHz with good reflection coefficient of − 27.14 dB and − 21.49 dB respectively. To validate the antenna performance, the simulated results for the proposed antenna are compared with measurements taken with fabricated antenna. The operating frequency band of proposed antenna is useful in L and S-band for PCS (1.85–1.99 GHz), UMTS (1.92–2.17 GHz), WLAN (2.4–2.484 GHz), and WiMAX (2.5–2.69 GHz). A stable peak gain of 2.9–3.84 dB and antenna efficiency of 81–91% is observed in entire resonating band. [ABSTRACT FROM AUTHOR]

As the world becomes more wireless, the demand for smaller antennas with wideband capabilities is growing. The performance characteristics of a miniaturized compound frequency reconfigurable microstrip patch antenna using an asymmetrical array patch as the top layer and a metamaterial DGS structure as the ground layer are discussed in this work. The focus of this research is on reconfigurability with a dynamic response over frequency and a customizable radiation pattern in a controlled environment. It's done by tinkering with radiating patch structures, which are analogous to switches and adjustable materials. This approach modifies the RF current travelling through the antenna construction to match the intended response and provides a reversible change to its attributes. In the High Frequency Structure Simulator, the proposed antenna structure of 11.5 mm × 11.5 mm reduced size is designed, simulated, and the results are analyzed, and after fabrication, the results such as return loss, VSWR, and impedance are validated using the Vector Network Analyzer, ANRITSU-MS2027C. The simulated and measured results shown with impedance bandwidth for 1.42 GHz, 3 GHz and 4.5 GHz. The antenna has a gain of + 4.7 dB overall and a directivity of + 5.3 dB. At 1.42 GHz, the antenna's return loss was − 19.58 dB, − 11.54 dB at 3 GHz, and − 13.91 dB at 4.5 GHz. The antenna spans three separate (L, S, and C) bands for common wireless applications over the range of 1–5 GHz, with a VSWR value of less than 2 throughout the entire impedance bandwidth. The antenna design is covered in detail, as well as associated results are shown. [ABSTRACT FROM AUTHOR]

The rise of heterogeneous networks including macro, micro, pico, femto, and WLAN presents new challenges in optimizing user's access to the networks. To fully utilize the capacity of such rich field of heterogeneous wireless connectivity, mobile devices should be able to select Radio Access Network (RAN) for their connection depending on their need. The proposed algorithm here is based on an autonomous agent at the mobile node and assisted by integration of distributed cloud services, e.g. the edge cloud. The selection of RAN is based on a Multi Attribute Decision Making process combined with the Reinforcement Learning that reinforces historical data collected from the edge cloud. Mobile agent is responsible for collecting data, executing the selection algorithm, possibly offloading the parts of the execution to the edge cloud, and providing feedback to the edge cloud after termination of the connection. The ultimate aim is to the design of RAN selection algorithm owned by autonomous and intelligent user agents that can significantly improve the user's experience in terms of network coverage, data rate, latency, and battery lifetime. Through extensive simulation scenarios, we demonstrate the stability and precision of our proposed algorithm. [ABSTRACT FROM AUTHOR]

This article presents a dual-band dual-polarized, slotted cylindrical dielectric resonator antenna (CDRA) for wireless applications. Multiple inverted pentagons with slotted aperture are used to radiate hybrid mode HEM11δ. The suggested radiator has two operating frequency bands: lower frequency band is from 3.75 to 3.96 GHz with 5.44% (210 MHz) fractional bandwidth resonating at 3.87 GHz while upper frequency band is from 6.58 to 8.4 GHz with 24.29% (1820 MHz) fractional bandwidth resonating at 6.63 GHz. The lower resonating band is generated because of multiple slots while upper resonating band is due to the combination of CDRA and multiple slots. The lower band is linearly polarized whereas the upper band is dual-polarized (linear/circular). Circular polarization (CP) characteristic is achieved at the upper frequency band by combining the effect of moon-type microstrip line and multiple slots. Axial ratio bandwidth (3-dB) is obtained about 7.06% (550 MHz) between 7.52 and 8.07 GHz with 0.62 dB minimum AR value at frequency 8.01 GHz. This radiator can be used in partially S and C-band applications. [ABSTRACT FROM AUTHOR]

In this paper, using in-depth simulations and measurements, a simple and compact design is engineered for making a circular ring microstrip patch antenna radiating element which is suitable for different ultra wide band (UWB) applications. This design approach is different because it has not utilized the usual method of using a set of electromagnetic equations and calculations to make the radiating antenna. Measurements and simulations were performed on Microwave CST. Using this measurement engineering approach, novelty of proposed antenna structure is obtained by making the required changes in the ground plane. The measurements showed that truncating the ground plane by a square shape structure of 2.5 mm by 2.5 mm size at the feed point was practically significant to provide an impedance bandwidth S 11 < - 10 dB ranging from 2.75 to 32.035 GHz with a VSWR which is less than 2. For this entire bandwidth the directivity has shown a variation from 0.8 to 7.9 dBi. The compact size (33 mm × 28 mm × 1.57 mm), low design complexity, very high bandwidth, good directivity and satisfying VSWR has made this antenna unique among all previously presented UWB antennas. [ABSTRACT FROM AUTHOR]

This paper presents the design, simulation and fabrication of a miniaturized wearable dual-band antenna put on a rigid substrate and operable at 2.45/5.8 GHz for wireless local area network applications. The electrical and radiation characteristics of the developed antenna were obtained by means of the technical insertion of a slot to tune the operating frequencies. To study the impact of the electromagnetic radiation of the structure of the human body, it is necessary to minimize the back radiation towards the user. Therefore, in this work, a multi-band artificial magnetic conductor (AMC) was placed directly above a dual-band planar inverted F antenna to achieve a miniaturization with excellent radiation performance. The simulations were carried out using the computer simulation technology CST Microwave Studio (CST MWS). A good agreement was achieved between the simulation and experimental results. The comparison of the measurement findings indicates that, when the antenna was backed by the AMC plane, the gain improved from 1.84 to 3.8 dB, in the lower band, and from 2.4 to 4.1 dB in the upper band. The front-to-back ratio of the AMC backed PIFA antenna was also enhanced. Then, to ensure that the proposed AMC structure is harmless to the human body, this prototype was placed on three-layer human tissue cubic model. It was observed that, due to the inclusion of an AMC plane, the peak specific absorption rate (SAR) decreased to 1.45 and 1.1 W/kg at 2.45 and 5.8 GHz, respectively (a reduction of around 3.7 W/kg, compared with an antenna without (AMC). [ABSTRACT FROM AUTHOR]

Design of simple and inexpensive multiband antennas covering different applications have been played prominent role in modern wireless communication systems and also attracted the researchers to do more research and investigation. Antennas became indispensible part in the front end of the wireless communication systems. Breakthrough in the developments of contemporary wireless communication systems has outspread the demand for a low profile, simple, inexpensive and versatile antennas operating at different modes. The quad band printed antenna for supporting Wi-Fi, WLAN, C-band and Wi-MAX applications is designed and analyzed in current article. This quad band antenna contains a slotted radiating patch on dielectric substrate and defected ground on opposite side. The quad band antenna operates at four distinct frequency bands of 2.41–2.58 GHz, 3.40–3.70 GHz, 3.94–4.62 GHz and 4.97–5.95 GHz respectively. It exhibits adequate return loss and gain over the operating bands. It is fed with microstrip line. The designed quad band antenna is fabricated and also taken measurements to examine its performance. [ABSTRACT FROM AUTHOR]