Amor Smida^1,2,*

CMC-Computers, Materials & Continua, Vol.71, No.1, pp. 1613-1623, 2022, DOI:10.32604/cmc.2022.022289 - 03 November 2021

Abstract High gain antennas are highly desirable for long-range wireless communication systems. In this paper, a compact, low profile, and high gain dielectric resonator antenna is proposed, fabricated, experimentally tested, and verified. The proposed antenna system has a cylindrical dielectric resonator antenna with a height of 9 mm and a radius of 6.35 mm as a radiating element. The proposed dielectric resonator antenna is sourced with a slot while the slot is excited with a rectangular microstrip transmission line. The microstrip transmission line is designed for a 50 Ω impedance to provide maximum power to the… More >

Abdelhameed Ibrahim^1,*, Hattan F. Abutarboush², Ali Wagdy Mohamed^3,4, Mohamad Fouad¹, El-Sayed M. El-kenawy^5,6

CMC-Computers, Materials & Continua, Vol.71, No.1, pp. 199-213, 2022, DOI:10.32604/cmc.2022.021886 - 03 November 2021

Abstract Metamaterial Antenna is a special class of antennas that uses metamaterial to enhance their performance. Antenna size affects the quality factor and the radiation loss of the antenna. Metamaterial antennas can overcome the limitation of bandwidth for small antennas. Machine learning (ML) model is recently applied to predict antenna parameters. ML can be used as an alternative approach to the trial-and-error process of finding proper parameters of the simulated antenna. The accuracy of the prediction depends mainly on the selected model. Ensemble models combine two or more base models to produce a better-enhanced model. In… More >

Imran Khan¹, Fahd N. Al-Wesabi², Marwa Obayya³, Anwer Mustafa Hilal⁴, Manar Ahmed Hamza⁴, Mohammed Rizwanullah⁴, Fahad Ahmed Al-Zahrani⁵, Hirofumi Amano⁶, Samih M. Mostafa^7,*

CMC-Computers, Materials & Continua, Vol.71, No.1, pp. 697-715, 2022, DOI:10.32604/cmc.2022.021847 - 03 November 2021

Abstract With the rapid development of wireless communication technology, the spectrum resources are increasingly strained which needs optimal solutions. Cognitive radio (CR) is one of the key technologies to solve this problem. Spectrum sensing not only includes the precise detection of the communication signal of the primary user (PU), but also the precise identification of its modulation type, which can then determine the a priori information such as the PU’ service category, so as to use this information to make the cognitive user (CU) aware to discover and use the idle spectrum more effectively, and improve the… More >

Shahid Habib¹, Ghaffer Iqbal Kiani², Muhammad Fasih Uddin Butt^1,3,*, Syed Muzahir Abbas^4,5, Abdulah Jeza Aljohani², Soon Xin Ng³

CMC-Computers, Materials & Continua, Vol.70, No.3, pp. 6177-6187, 2022, DOI:10.32604/cmc.2022.021644 - 11 October 2021

Abstract A low-profile ultra-wideband (UWB) band-stop frequency selective surface (FSS) is designed for S-, C-, X- and Ku-bands communication applications. The FSS is constructed by using square and circular loop elements printed on the top and bottom sides of the RO3210 substrate. The FSS has been designed to reduce the electromagnetic interference (EMI) as well as to mitigate the harmful effects of electromagnetic radiation on the human body caused by different radio devices. The dimension and size of the UWB FSS have been reduced to 0.12 λ × 0.12 λ and 90%, respectively, as compared to More >

Mosleh M. Abualhaj^*, Abdelrahman H. Hussein, Qasem M. Kharma, Qusai Y. Shambour, Sumaya N. Al-Khatib

Intelligent Automation & Soft Computing, Vol.31, No.3, pp. 1971-1980, 2022, DOI:10.32604/iasc.2022.021458 - 09 October 2021

Abstract IPv6 protocol is the future of IP networks due to its large IP address capacity. One of the key consequences of this large capacity is that the IP protocol header has enlarged from 20-byte in IPv4 to 40-byte in IPv6. This will consume a considerable share of the bandwidth (BW) for VoIP applications, which produce small packets in tens of bytes only. To handle this issue, we have introduced an efficient technique to use the superfluous fields in the VoIP packet header, including the IPv6 header, to hold the voice data of the packet. This… More >

D. Kothandaraman¹, A. Balasundaram^2,*, R. Dhanalakshmi³, Arun Kumar Sivaraman⁴, S. Ashokkumar⁵, Rajiv Vincent⁴, M. Rajesh⁴

CMC-Computers, Materials & Continua, Vol.70, No.2, pp. 3875-3890, 2022, DOI:10.32604/cmc.2022.020744 - 27 September 2021

Abstract Internet of Things (IoT) is becoming popular nowadays for collecting and sharing the data from the nodes and among the nodes using internet links. Particularly, some of the nodes in IoT are mobile and dynamic in nature. Hence maintaining the link among the nodes, efficient bandwidth of the links among the mobile nodes with increased life time is a big challenge in IoT as it integrates mobile nodes with static nodes for data processing. In such networks, many routing-problems arise due to difficulties in energy and bandwidth based quality of service. Due to the mobility… More >

Qasem M. Kharma^*, Abdelrahman H. Hussein, Faris M. Taweel, Mosleh M. Abualhaj, Qusai Y. Shambour

Intelligent Automation & Soft Computing, Vol.31, No.2, pp. 869-883, 2022, DOI:10.32604/iasc.2022.020415 - 22 September 2021

Abstract The widespread and desirable features of IP and IEEE 802.11 networks have made these technologies a suitable medium for carrying voice over IP (VoIP). However, a bandwidth (BW) exploitation obstacle emerges when 802.11 networks are used to carry VoIP traffic. This BW exploitation obstacle is caused by the large 80-byte preamble size of the VoIP packet and a waiting time of 765 μs for each layer 2 VoIP frame. As a solution, IEEE 802.11n was consequently designed with a built-in layer 2 frame aggregation feature, but the adverse impact on the VoIP performance still needed More >

Junxiang Jiang^1,2, Shaogang Liu^1,*, Lifeng Feng³

Energy Engineering, Vol.118, No.5, pp. 1287-1303, 2021, DOI:10.32604/EE.2021.015354 - 16 July 2021

Abstract This paper presents a 2DOF nonlinear piezoelectric energy harvester for improving the efficiency of energy harvesting in low frequency range. The device consisted of an L-shaped piezoelectric cantilever with a magnet at the tip of the first beam and two external magnets on the pedestal. The distance between the magnets which generated nonlinear magnetic attraction was adjusted such that the system can exhibit monostable or bistable characteristics. First, the model of this piezoelectric energy harvester was established and the dynamic equation was derived based on the magnetic attractive force. Then, the nonlinear dynamic responses of 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 >

Mosleh M. Abualhaj^*, Qusai Y. Shambour, Abdelrahman H. Hussein, Qasem M. Kharma

CMC-Computers, Materials & Continua, Vol.68, No.1, pp. 1271-1283, 2021, DOI:10.32604/cmc.2021.014928 - 22 March 2021

Abstract Voice over Internet Protocol (VoIP) is widely used by companies, schools, universities, and other institutions. However, VoIP faces many issues that slow down its propagation. An important issue is poor utilization of the VoIP service network bandwidth, which results from the large header of the VoIP packet. The objective of this study is to handle this poor utilization of the network bandwidth. Therefore, this study proposes a novel method to address this large header overhead problem. The proposed method is called zero size payload (ZSP), which aims to reemploy and use the header information (fields) More >