The study and exploration of massive multiple-input multiple-output (MMIMO) and millimeter-wave wireless access technology has been spurred by a shortage of bandwidth in the wireless communication sector. Massive MIMO, which combines antennas at the transmitter and receiver, is a key enabler technology for next-generation networks to enable exceptional spectrum and energy efficiency with simple processing techniques. For massive MIMOs, the lower band microwave or millimeter-wave band and the antenna are impeccably combined with RF transceivers. As a result, the 5G wireless communication antenna differs from traditional antennas in many ways. A new concept of the MIMO tri-band hexagonal antenna array is being introduced for next-generation cellular networks. With a total scaling dimension of 150 × 75 mm2, the structure consists of multiple hexagonal fractal antenna components at different corners of the patch. The radiating patch resonates at 2.55–2.75, 3.45–3.7, and 5.65–6.05 GHz (FR1 band) for better return loss (S11) of more than 15 dB in all three operating bands. The coplanar waveguide (CPW) feeding technique and defective ground structure in the ground plane have been employed for effective impedance matching. The deviation of the main lobe of the radiation pattern is achieved using a two-element microstrip Taylor antenna array with series feeding, which also boosts the antenna array’s bandwidth and minimizes sidelobe. The proposed antenna is designed, simulated, and tested in far-field radiating conditions and generates tri-band S-parameters with sufficient separation and high-quality double-polarized radiation. The fabrication and testing of MIMO antennas were completed, where the measurement results matched the simulation results. In addition, the 5G smartphone antenna system requires a new, lightweight phased microwave antenna (μ-wave) with wide bandwidth and a fire extender. Because of its decent performance and compact architectures, the proposed smartphone antenna array architecture is a better entrant for upcoming 5G cellular implementations.

A Novel Approach of Design and Analysis of a Hexagonal Fractal Antenna Array (HFAA) for Next-Generation Wireless Communication

Mobile Ad hoc Network (MANET) is a type of wireless networks that provides numerous applications in different areas Security of MANET had become one of the hottest topics in networks fields MANET is vulnerable to different types of attacks that affect its functionality and connectivity The black-hole attack is considered one of the most widespread active attacks that degrade the performance and reliability of the network as a result of dropping all incoming packets by the malicious node Black-hole node aims to fool every node in the network that wants to communicate with another node by pretending that it always has the best path to the destination node AODV is a reactive routing protocol that has no techniques to detect and neutralize the black-hole node in the network In this research, we enhanced AODV by integrating a new lightweight technique that uses timers and baiting in order to detect and isolate single and cooperative black-hole attacks During the dynamic topology changing the suggested technique enables the MANET nodes to detect and isolate the black-hole nodes in the network The implementation of the proposed technique is performed by using NS-235 simulation tools The results of the suggested technique in terms of Throughput, End-to-End Delay, and Packet Delivery Ratio are very close to the native AODV without black holes

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Detecting and Isolating Black-Hole Attacks in MANET Using Timer Based Baited Technique

This paper premeditates an optimal design of fractal antenna with modified ground structure for wideband applications. The proposed antenna has been designed by taking numerous iterations started from 0th to 3rd. To attain the wideband characteristics, the partial ground plane has been introduced in the 3rd iteration, and the length of the ground plane has been varied to enhance the bandwidth. The maximum value of bandwidth has been adorned in the final iteration as 1.88 and 0.20 GHz. Further, this bandwidth has been improved and embellished as 2.48 GHz within the frequency range of 3–6 GHz by employing horizontal and vertical extensions in the partial ground plane. Antenna is simulated by using HFSS and performance parameters of antenna like return loss (S11 ≤ − 10 dB), gain and radiation efficiency are in the acceptable limits. The maximum value of gain is reported as 5.1 dB and radiation pattern is also omnidirectional. The proposed antenna is useful for the wireless applications as WiMAX (3.4–3.69 GHz) and WLAN (5.15–5.35 and 5.72–5.82 GHz) Simulated and experimental results are also juxtaposed and found in good agreement with each other.

An Optimal Design of Fractal Antenna with Modified Ground Structure for Wideband Applications

Compact high gain UWB antenna using fractal geometry and UWB‐AMC

An asymmetrically CPW-fed octagonal Sierpinski fractal antenna is designed for ultrawideband applications. It comprises of a second iterative fractal radiating patch, microstrip feedline and asymmetrical coplanar waveguide ground planes. An impedance bandwidth of 3.73 GHz to more than 20 GHz is achieved. Stable radiation patterns and desirable gain characteristics are observed. The simulated and experimental results are found to be in good agreement. The designed antenna structure has advantages of wide bandwidth and miniaturized dimensions over already reported UWB antenna structures. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1738–1745, 2016

Asymmetrically CPW‐fed octagonal sierpinski UWB fractal antenna

This paper presents the hexagonal microstrip fractal antenna (HMSFA) for ultra wideband wireless communication applications. Hexagonal antenna is powered through co-planar waveguide (CPW) feed structure. The stepping fed configuration is used to improve the antenna electrical characteristics at the centre and higher frequencies in the FCC designed UWB frequency range from 3.1 to 10.6 GHz. The proposed antenna uses a fractal technique to analyze its UWB characterization. The hexagon antenna is designed, simulated and fabricated on a polyamide substrate of dielectric constant ɛ r  = 4.3, thickness t  = 1.53 mm, loss tangent tan δ  = 0.004 and lande G factor 2. The operating bandwidth of the proposed fractal antenna is about 9 GHz more than UWB range. The size of the radiating patch is about 26 mm × 30 mm and the sided length s  = 15 mm, achieves good impedance matching, constant gain, steady radiation patterns, multi resonant and constant group delay over an UWB frequency range from 3.1 to 10.6 GHz. This antenna creates the fractal geometry inside the patch with similar in shape but different in sizes. The proposed antenna is fabricated and experimental results are verified in an anechoic chamber of millimetre and antenna lab.

CPW fed hexagonal micro strip fractal antenna for UWB wireless communications

Mobile Ad Hoc NETworks (MANETs) have become eminent resources for providing communication to military and other defence establishments operating in the conventional battlefield scenario in enemy territory or Counter Insurgency/Counter Terrorism operations beyond the reach of a permanent network infrastructure. However, MANET's inherent topology lack in defensive procedures and are thus, vulnerable to security attacks. Single and Cooperative Black hole attacks are one of the prominent security coercions in MANET wherein malicious nodes deceives source node by promoting self-destined routes during the route discovery process and absorbs the packets meant for Destination node. A black hole node might cooperate with other black hole node resulting in a cooperative Black hole Attack. Researchers around the globe have proposed diverse detection techniques and schemes to detect this type of security attack. This paper proposes a hybrid technique to alleviate the effects of Black hole attack keeping the military perspective in mind. Simulations have been done using NS-2 simulator. Metrics used are Delay, throughput and Packet Delivery Ratio.

Mitigating effects of Black hole Attack in Mobile Ad-Hoc NETworks: Military perspective

In order to implement the interweave cognitive radio solutions, the research for finding sparsely utilized spectrum bands has revealed the VHF and UHF television broadcast bands, known as television white spaces (TVWS) as the foremost candidate The TVWS quantification and throughput analysis conducted via several measurement attempts and field trials uncover various facets of the TVWS spectrum measurement Consequently, the conclusions obtained may be processed to get a statistical knowledge about spectrum availability in a particular geographic region and hence utilized for spectrum management This paper explores inherent methodologies used for TVWS assessment and provides a comprehensive overview of the TVWS regulatory norms, results obtained by TVWS measurement campaigns and field trials conducted worldwide In addition, research issues, implementation challenges and future directions for TVWS measurement procedure are highlighted

TV white spaces exploration for cognitive radio: taxonomy and research issues

A novel multiresonance loop shape microstrip antenna (MRLMSA) for ultra wide band wireless communication applications is presented. The designed radiating antenna consists of a two loop shaped ring resonators around the single monopole hexagon patch. This antenna is powered through stepped co-planar waveguide (CPW) fed. The stepping fed is used to improve the antenna electrical characteristics at the centre and at higher frequencies. The stepping fed and ground formation will also provide the impedance matching with the radiating patch. This antenna is used for characterisation in ultra wide band frequency range from 3.1 GHz to 10.6 GHz. The antenna is designed and simulated on an Fr4_epoxy substrate of dimensions (L) × (W) = 72.25 mm × 51 mm having dielectric constant εr = 4.4, relative permeability = 1, thickness t = 1.53 mm, loss tangent tan δ = 0.002 and lande G factor 2. The size of the radiating patch is specified by Length × Width is (L1) × (W1) and edge length is (S1) for impedance matching, constant gain, steady radiation patterns, and constant group delay over the UWB frequency range. The two loop rings are used around the monopole hexagon is to provide the multiresonance radiation characteristics. The speciality of the design and its dimensions is that, within two loop rings and a monopole patch it gives multiresonance response in the UWB frequency range from 3.1 GHz to 10.6 GHz. An optimized MRLMSA is designed and simulated on an Ansoft-HFSS simulation software and a comparative statement of result is also proposed. This antenna is useful in the UWB wireless communication systems i.e. MIMO-Multi-Input Multi-Output UWB system for short range, higher power transmission with higher bandwidth requirement. This antenna is also used in other wireless systems such as WLAN, WiMax etc for notch (filter)applications.

Design of multiresonance loop shape microstrip antenna for ultra wide band wireless communication applications

https://onlinelibrary.wiley.com/doi/pdf/10.1002/spy2.86

C.R. Suthikshn Kumar

Papers

CPW fed hexagonal micro strip fractal antenna for UWB wireless communications

Mitigating effects of Black hole Attack in Mobile Ad-Hoc NETworks: Military perspective

TV white spaces exploration for cognitive radio: taxonomy and research issues

Design of multiresonance loop shape microstrip antenna for ultra wide band wireless communication applications

Classification of malicious process using high‐level activity based dynamic analysis