Hussain Askari, Niamat Hussain, Domin Choi, Md. Abu Sufian, Anees Abbas, Nam Kim^*

CMC-Computers, Materials & Continua, Vol.69, No.3, pp. 2997-3013, 2021, DOI:10.32604/cmc.2021.018855 - 24 August 2021

Abstract This paper presents an AMC (artificial magnetic conductor)-based wideband circularly polarized printed monopole antenna for unidirectional radiation. The antenna includes an AMC reflector, a coplanar waveguide (CPW) feed structure to excite the antenna, a ground plane with a rectangular slot on the left side of feedline, and an asymmetrical ground plane on its right side. The induced surface currents on CWP feedline, rectangularly slotted, and asymmetrical ground planes cause circularly polarized radiations. The AMC reflector consisting periodic metallic square patches is used instead of the conventional PEC (perfect electric conductor) reflector, the distance between the More >

T. Prabhu^1,*, S. Chenthur Pandian²

CMC-Computers, Materials & Continua, Vol.69, No.2, pp. 2549-2562, 2021, DOI:10.32604/cmc.2021.018793 - 21 July 2021

Abstract This paper proposes, demonstrates, and describes a basic T-shaped Multi-Input and Multi-Output (MIMO) antenna with a resonant frequency of 3.1 to 10.6 GHz. Compared with the U-shaped antenna, the mutual coupling is minimized by using a T-shaped patch antenna. The T-shaped patch antenna shapes filter properties are tested to achieve separation over the 3.1 to 10.6 GHz frequency range. The parametric analysis, including width, duration, and spacing, is designed in the MIMO applications for good isolation. On the FR4 substratum, the configuration of MIMO is simulated. The appropriate dielectric material ɛ_r = 4.4 is introduced using More >

Fahd N. Al-Wesabi^1,2,*, Murad A. A. Almekhlafi³, Huda G. Iskandar^2,4, Adnan Zain⁵, Saleh Alzahrani⁶, Mohammed Alamgeer⁶, Nadhem Nemri⁶, Sami Dhabi⁶, Mohammad Medani⁶, Ali. M. Al-Sharafi^2,7

CMC-Computers, Materials & Continua, Vol.69, No.2, pp. 1979-1994, 2021, DOI:10.32604/cmc.2021.018390 - 21 July 2021

Abstract In recent years, there has been an increasing demand to improve cellular communication services in several aspects. The aspect that received the most attention is improving the quality of coverage through using smart antennas which consist of array antennas. this paper investigates the main characteristics and design of the three types of array antennas of the base station for better coverage through simulation (MATLAB) which provides field and strength patterns measured in polar and rectangular coordinates for a variety of conditions including broadsides, ordinary End-fire, and increasing directivity End-fire which is typically used in smart More >

Ayman Abdulhadi Althuwayb¹, Fazirulhisyam Hashim², Jiun Terng Liew², Imran Khan³, Jeong Woo Lee⁴, Emmanuel Ampoma Affum⁵, Abdeldjalil Ouahabi^6,7,*, Sébastien Jacques⁸

CMC-Computers, Materials & Continua, Vol.69, No.1, pp. 679-694, 2021, DOI:10.32604/cmc.2021.015421 - 04 June 2021

Abstract With the rapid development of the mobile internet and the internet of things (IoT), the fifth generation (5G) mobile communication system is seeing explosive growth in data traffic. In addition, low-frequency spectrum resources are becoming increasingly scarce and there is now an urgent need to switch to higher frequency bands. Millimeter wave (mmWave) technology has several outstanding features—it is one of the most well-known 5G technologies and has the capacity to fulfil many of the requirements of future wireless networks. Importantly, it has an abundant resource spectrum, which can significantly increase the communication rate of… More >

Shakir Ullah¹, Sadiq Ullah¹, Inzamam Ahmad¹, Wasi Ur Rehman Khan¹, Toufeeq Ahmad¹, Usman Habib², Mahmoud A. Albreem³, Mohammed H. Alsharif⁴, Peerapong Uthansakul^5,*

CMC-Computers, Materials & Continua, Vol.68, No.3, pp. 3015-3027, 2021, DOI:10.32604/cmc.2021.015549 - 06 May 2021

Abstract In this paper, the design and experimental evaluation of a hexagonal-shaped coplanar waveguide (CPW)-feed frequency reconfigurable antenna is presented using flame retardant (FR)-4 substrate with size of 37 × 35 × 1.6 mm³. The antenna is made tunable to three different modes through the status of two pin diodes to operate in four distinct frequency bands, i.e., 2.45 GHz wireless fidelity (Wi-Fi) in MODE 1, 3.3 GHz (5G sub-6 GHz band) in MODE 2, 2.1 GHz (3G Long Term Evolution (LTE)-advanced) and 3.50 GHz Worldwide Interoperability for Microwave Access (WiMAX) in MODE 3. The optimization through… More >

Ikhlas Ahmad¹, Haris Dildar¹, Wasi Ur Rehman Khan¹, Sadiq Ullah¹, Shakir Ullah¹, Mahmoud A. Albreem², Mohammed H. Alsharif³, Peerapong Uthansakul^4,*

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 2563-2578, 2021, DOI:10.32604/cmc.2021.016813 - 13 April 2021

Abstract In this paper, low profile frequency reconfigurable monopole antenna is designed on FR-4 substrate with a compact size of 30 mm³ × 20 mm³ × 1.6 mm³. The antenna is tuned to four different modes through three pin diode switches. In Mode 1 (SW1 to SW3 = OFF), antenna covers a wideband of 3.15–8.51 GHz. For Mode 2 (SW1 = ON, SW2 to SW3 = OFF), the proposed antenna resonates at 3.5 GHz. The antenna shows dual band behavior and covers 2.6 and 6.4 GHz in Mode 3 (SW1 and SW2 = ON, SW3 = OFF). The… More >

Shahid Khan^1,*, Xin Cheng Ren², Haider Ali³, Camel Tanougast¹, Abdul Rauf⁴, Safdar Nawaz Khan Marwat⁵, Muhammad Rizwan Anjum⁶

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 2095-2109, 2021, DOI:10.32604/cmc.2021.016811 - 13 April 2021

Abstract In this work, a novel compact wideband reconfigurable circularly polarised (CP) dielectric resonator antenna (DRA) is presented. The L-shaped Dielectric resonator antenna is excited by an inverted question mark shaped feed. This arrangement of feed-line helps to generate two orthogonal modes inside the DR, which makes the design circularly polarised. A thin micro-strip line placed on the defected ground plane not only helps to generate a wideband response but also assist in the positioning of the two diode switches. These switches located at the left and right of the micro-strip line helps in performing two… More >

Huy Hung Tran^1,2, Khoa Nguyen-Dang^1,2,*, Niamat Hussain³

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 2487-2498, 2021, DOI:10.32604/cmc.2021.016027 - 13 April 2021

Abstract A single-layer design of non-uniform metasurface (MS) based circularly polarized (CP) antenna with wideband operation characteristic is proposed and investigated in this paper. The antenna is excited by a truncated corner squared patch as a primary radiating CP source. Then, a non-uniform MS is placed in the same layer with the driven patch. Besides increasing the impedance bandwidth, the non-uniform MS also generates two additional CP bands in the high frequency band, leading to significantly increase the antenna’s overall performances. The use of non-uniform MS distinguishes our design from the other CP MS based antennas… More >

Muhammad Asghar Khan^1,*, Fazal Noor², Insaf Ullah³, Sajjad ur Rehman⁴, Shibli Nisar⁵, Mohaira Ahmad⁵

Computer Systems Science and Engineering, Vol.38, No.1, pp. 47-63, 2021, DOI:10.32604/csse.2021.016430 - 01 April 2021

Abstract The Flying Ad-hoc Networks (FANETs) is characterized by the transition from a single large Unmanned Aerial Vehicle (UAV) to multiple small UAVs connected in an ad-hoc fashion. Since high mobility is the core feature of such networks, they are prone to route breaks within the links. The issue of connectivity loss can be coped with, to some extent, by making use of omnidirectional antennas. Such modification, however, curtails Quality-of-Service (QoS) requirements of networks in terms of bandwidth, media access delay, coverage and others. Alternately, directional antennas have advantages over omnidirectional antennas such as improved transmission… More >

Zhoulei Cao¹, Qijun Wen¹, Xiaoliang Wang^1,*, Qing Yang¹, Frank Jiang²

Journal on Internet of Things, Vol.3, No.1, pp. 11-17, 2021, DOI:10.32604/jiot.2021.010404 - 16 March 2021

Abstract The miniaturization and endurance of wearable devices have been the research direction for a long time. With the development of nanotechnology and the emergence of microelectronics products, people have explored many new strategies that may be applied to wearable devices. In this overview, we will summarize the recent research of wearable devices in these two directions, and summarize some available related technologies. More >