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

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 simulation modeling shows that… 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

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 same antenna covers… 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

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 switching operations. The novel compact… 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

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 in literature, in which the… 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

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 range, spatial reuse and high… 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

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 >

Kaisarul Islam¹, Tabia Hossain¹, Mohammad Monirujjaman Khan^1,*, Mehedi Masud², Roobaea Alroobaea²

Computer Systems Science and Engineering, Vol.37, No.1, pp. 19-32, 2021, DOI:10.32604/csse.2021.015528

Abstract In this paper performance of three different designs of a 60 GHz high gain antenna for body-centric communication has been evaluated. The basic structure of the antenna is a slotted patch consisting of a rectangular ring radiator with passive radiators inside. The variation of the design was done by changing the shape of these passive radiators. For free space performance, two types of excitations were used—waveguide port and a coaxial probe. The coaxial probe significantly improved both the bandwidth and radiation efficiency. The center frequency of all the designs was close to 60 GHz with a bandwidth of more than… More >

Amir Haider¹, MuhibUr Rahman², Hamza Ahmad³, Mahdi NaghshvarianJahromi⁴, Muhammad Tabish Niaz¹, Hyung Seok Kim^1,*

CMC-Computers, Materials & Continua, Vol.67, No.2, pp. 2243-2254, 2021, DOI:10.32604/cmc.2021.015613

Abstract This paper introduces a compact dual notched UWB antenna with an independently controllable WLAN notched band integrated with fixed WiMAX band-notch. The proposed antenna utilizes a slot resonator placed in the main radiator of the antenna for fixed WiMAX band notch, while an inverted L-shaped resonator in the partial ground plane for achieving frequency agility within WLAN notched band. The inverted L-shaped resonator is also loaded with fixed and variable capacitors to control and adjust the WLAN notch. The WLAN notched band can be controlled independently with a wide range of tunability without disturbing the WiMAX band-notch performance. Step by… More >

Omar A. Saraereh^*

CMC-Computers, Materials & Continua, Vol.67, No.1, pp. 1121-1136, 2021, DOI:10.32604/cmc.2021.015066

Abstract Wireless communication is one of the rapidly-growing fields of the communication industry. This continuous growth motivates the antenna community to design new radiating structures to meet the needs of the market. The 5G wireless communication has received a lot of attention from both academia and industry and significant efforts have been made to improve different aspects, such as data rate, latency, mobility, reliability and QoS. Antenna design has received renewed attention in the last decade due to its potential applications in 5G, IoT, mmWave, and massive MIMO. This paper proposes a novel design of broadband antenna for 5G mmWave and… More >

Amir Haider¹, Tayyaba Khan², MuhibUr Rahman³, Byung Moo Lee¹, Hyung Seok Kim^1,*

CMC-Computers, Materials & Continua, Vol.66, No.3, pp. 2241-2251, 2021, DOI:10.32604/cmc.2021.013908

Abstract A coplanar waveguide-fed quintuple band antenna with a slotted circular-shaped radiator for wireless applications with a high isolation between adjacent bands is presented in this paper. The proposed antenna resonates at multiple frequencies with corresponding center frequencies of 2.35, 4.92, 5.75, 6.52, and 8.46 GHz. The intended functionality is achieved by introducing a circular disc radiator with five slots and a U-shaped slot in the feed. The proposed antenna exhibits coverage of the maximum set of wireless applications, such as satellite communication, worldwide interoperability for microwave access, wireless local area network (WLAN), long-distance radio telecommunications, and X-band/Satcom wireless applications. The… More >