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Article
Publication date: 11 June 2018

Saadi Djidel, Mohamed Bouamar and Djamel Khedrouche

Modern wireless communication application requires an antenna system to meet the requirements of miniaturization and wideband characteristic. In recent years, several…

Abstract

Purpose

Modern wireless communication application requires an antenna system to meet the requirements of miniaturization and wideband characteristic. In recent years, several antenna designs, that meet these requirements, have been proposed in the literature. In this context, the purpose of this paper is to design a new microstrip monopole antenna with a bandwidth enhancement and size reduction for ultra wideband application.

Design/methodology/approach

The patch, of leaf of a plant shape, the feed line and the ground plane are printed on the inexpensive FR4 substrate material with permittivity 4.4 and loss tangent 0.02. To obtain optimal dimensions, a parametric study is conducted through numerical computations by using electromagnetic simulators HFSS and CST. A prototype of the optimized antenna is fabricated and subjected to a series of simulations and measurements.

Findings

The measurement results show a −10 dB impedance bandwidth of 6.7 GHz (3.5 GHz-10.2 GHz) which can cover the whole bandwidth requirements of an ultra wideband application. The designed antenna exhibits nearly symmetric and omnidirectional radiations patterns over the operating band, which is a sought-after behavior in microstrip patch antennas and has overall size of 35 × 31 mm2.

Originality/value

The proposed microstrip monopole antenna is very useful for modern wireless communications systems because of its compact size, its capability of covering the whole ultra wideband frequency band and its good radiation characteristics.

Details

World Journal of Engineering, vol. 15 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 17 June 2021

Lalitha Bhavani Konkyana and Sudhakar Alapati

This paper aims to state the configuration of the proposed antenna which is competent to many networks such as LTE and X band applications. The experimental study…

Abstract

Purpose

This paper aims to state the configuration of the proposed antenna which is competent to many networks such as LTE and X band applications. The experimental study encountered the significance of the proposed antenna.

Design/methodology/approach

A novel compact Kuznets curve with parabola-shaped quad-band notched antenna is demonstrated in this paper. The presented prototype is ascertained on a composite material composed of woven fiberglass cloth with an epoxy resin binder. The resulting ultra-wideband antenna ranges 3.1–3.54 GHz, 5.17–5.51 GHz, 5.74–6.43 GHz and 6.79–7.60 GHz. To avoid the frequency bands which cause UWB interference,the projected antenna has been incorporated with slotted patch. The proposed antenna design is attained in four steps. The simple circular patch antenna model with defected ground plane is subjected to stepwise progression by including parabola-shaped slot and U shaped slot on the patch to attain four notched bands.

Findings

This projected antenna possesses an optimal bond among simulated and measured outcomes,which is more suitable for the quad notched band applications. Substrate analysis is done by varying substrate material, and notch behavior is presented. The proposed method’s optimum performance in metrics such as return loss, voltage standing wave ratio and radiation pattern varies its frequency range from 2.56 to 7.6 GHz.

Originality/value

The antenna adaptation of the defected ground plane has achieved through the quad notched band with operating frequency ranges 2.56 to 7.6 GHz and with eliminated frequency ranges 3.55–5.16 GHz, 5.52–5.73 GHz, 6.44–6.78 GHz and 7.66–10.6 GHz.

Details

International Journal of Pervasive Computing and Communications, vol. 17 no. 3
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 2 March 2015

Łukasz Januszkiewicz and Sławomir Hausman

The purpose of this paper is to compare the properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to…

Abstract

Purpose

The purpose of this paper is to compare the properties of simplified physical and corresponding numerical human body models (phantoms) and verify their applicability to path loss modeling in narrowband and ultra-wideband on-body wireless body area networks (WBANs). One of the models has been proposed by the authors.

Design/methodology/approach

Two simplified numerical and two physical phantoms for body area network on-body channel computer simulation and field measurement results are presented and compared.

Findings

Computer simulations and measurements which were carried out for the proposed simplified six-cylinder model with various antenna locations lead to the general conclusion that the proposed phantom can be successfully used for experimental investigation and testing of on-body WBANs both in ISM and UWB IEEE 802.15.6 frequency bands.

Research limitations/implications

Usage of the proposed phantoms for the simulation/measurement of the specific absorption rate and for off-body channels are not within the scope of this paper.

Practical implications

The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies. The model is most suitable for wearable antenna radiation pattern simulation and measurement.

Social implications

Presented results facilitate applications of WBANs in medicine and health monitoring.

Originality/value

A new six-cylinder phantom has been proposed. The proposed simplified phantom can be easily made with a low cost in other laboratories and be used both for research and development of WBAN technologies.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 6 February 2009

Xia Zhang, Johan Liu, Camilla Kärnfelt, Shiwei Ma, Xu Wang, Linqin Meng and Herbert Zirath

Liquid Crystal Polymer (LCP) materials are considered to be promising substrates for wireless applications because of their excellent properties. The purpose of this paper…

Abstract

Purpose

Liquid Crystal Polymer (LCP) materials are considered to be promising substrates for wireless applications because of their excellent properties. The purpose of this paper is to describe now a novel and compact microstrip ultra‐wideband bandpass filter (UWB BPF) with ultra‐fine conductor traces working over 22 to 29 GHz is fabricated on LCP substrates.

Design/methodology/approach

Using standard processing technology, such as photolithography, plasma pretreatment, sputter deposition and wet etching, a microstrip UWB BPF is fabricated on LCP substrates. In order to obtain better adhesion between LCP substrate and copper, the oxygen plasma pretreatment of the LCP substrate surface and a thin titanium adhesion layer are introduced before a copper layer is sputter‐deposited onto the substrate.

Findings

The measured and the simulated results agree well. The measured insertion loss is about 8 dB in the passband of the bandpass filter, which is a little high compared to the simulated result (∼5 dB). The out of band performance at both the high frequency and low frequency is very good, almost higher than 35 dB.

Originality/value

This paper presents the realization of (UWB BPF) working over 22 to 29 GHz based on an LCP substrate, which demonstrates the feasibility of the application of the LCP substrate in RF wireless systems and also gives some useful information for later research.

Details

Circuit World, vol. 35 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 5 December 2019

Bo Cao, Shibo Wang, Shirong Ge, Wanli Liu, Shijia Wang and Shixue Yi

Wireless network localization technology is very popular in recent years and has attracted worldwide attention. The purpose of this paper is to improve the localization…

Abstract

Purpose

Wireless network localization technology is very popular in recent years and has attracted worldwide attention. The purpose of this paper is to improve the localization accuracy of ultra-wideband (UWB) with lower localization error taking into consideration the special real environment with the closed long and narrow space.

Design/methodology/approach

The principle of multidimensional scaling (MDS), particle swarm optimization (PSO) and Taylor series expansion algorithm (Taylor-D) were introduced. A novel positioning algorithm, MDS-PSO-Taylor was proposed to minimize the localization error. MDS-PSO algorithm provided a more accurate preliminary coordinate by applying the PSO algorithm so that the Taylor-D was used for further enhancing the localization accuracy.

Findings

Experimental results manifested that the proposed algorithm, providing small localization error value and higher positioning accuracy, can effectively reduce errors and achieve better performance in terms of the considerable improvement of localization accuracy.

Originality/value

The presented study with the real environment test attempts to demonstrate the proposed algorithm is hopeful to be applied to the underground environment for in the future.

Details

Sensor Review, vol. 40 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 13 June 2016

Slawomir Koziel and Adrian Bekasiewicz

– The purpose of this paper is to investigate strategies and algorithms for expedited design optimization and explicit size reduction of compact ultra-wideband (UWB) antennas.

Abstract

Purpose

The purpose of this paper is to investigate strategies and algorithms for expedited design optimization and explicit size reduction of compact ultra-wideband (UWB) antennas.

Design/methodology/approach

Formulation of the compact antenna design problem aiming at explicit size reduction while maintaining acceptable electrical performance is presented. Algorithmic frameworks are described suitable for handling various design situations and involving simulation models without and with response gradients available. Numerical and experimental case studies are provided demonstrating feasibility of solving real-world miniaturized antenna design tasks.

Findings

It is possible, through appropriate combination of the global and local optimization methods, surrogate modeling techniques and response correction methods, to find optimum dimensions of antenna structures that minimize antenna size while maintaining acceptable electrical performance. Design optimization can be performed at practically feasible computational costs.

Research limitations/implications

The study summarizes recent advances in miniaturization-oriented design optimization of UWB antennas. The presented techniques reach far beyond the commonly used design approaches based on parameter sweeps and similar hands-on methods, particularly in terms of automation, reliability, and reduction of the computational costs of the design processes.

Originality/value

The proposed design problem formulation and algorithmic frameworks proved useful for rapid design of compact UWB antenna structures, which is extremely challenging when using conventional methods. To the knowledge, this is the first attempt to efficient solving of this type of design problems, especially in the context of explicit antenna size reduction.

Article
Publication date: 9 November 2012

Ademola O. Kaka, Mehmet Toycan, Vali Bashiry and Stuart D. Walker

The purpose of this paper is to describe a modified Hilbert‐based fractal antenna for ultra wideband (UWB) wireless applications. Simulation results show excellent…

Abstract

Purpose

The purpose of this paper is to describe a modified Hilbert‐based fractal antenna for ultra wideband (UWB) wireless applications. Simulation results show excellent multi‐band characteristics for UWB wireless applications.

Design/methodology/approach

A Hilbert curve‐based fractal is optimised for self‐replicating, space‐filling and self‐avoiding properties. In the proposed design, the Hilbert curve is applied to a rectangle as an initial iteration and maintained for the later iterations. Additionally, a Yagi‐like strip is removed from the second iteration of the Hilbert patch and a hexagonal portion is removed from the substrate to achieve good optimization. The antenna feed is created through a micro‐strip line with a feeding section. Finally, a partial ground plane technique is used for improved impedance matching characteristics. A finite element method (FEM) is used to simulate the modified Hilbert model with commercially available Ansoft HFSS software.

Findings

The proposed antenna is miniaturized (39 mm length×30 mm width) and has multi‐band characteristics. The simulation results show that the antenna has a reflection coefficient characteristic of <−10 dB, a linear phase reflection coefficient, better than 65 percent radiation efficiency, 2.2‐4 dBi antenna gain and nearly omni‐directional radiation pattern properties over the UWB bandwidth (3.1‐10.6 GHz).

Originality/value

The antenna shows promising characteristics for the full 7.5 GHz UWB bandwidth. In addition, the performance is achieved by using laceration techniques on the Hilbert patch and substrate, respectively. A partial ground plane ensures impedance matching of 50 over full UWB bandwidth. The simulation analysis of the modified Hilbert fractal antenna design constitutes the main contribution of the paper.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 12 June 2017

Slawomir Koziel and Adrian Bekasiewicz

This paper aims to assess control parameter setup and its effect on computational cost and performance of deterministic procedures for multi-objective design optimization…

Abstract

Purpose

This paper aims to assess control parameter setup and its effect on computational cost and performance of deterministic procedures for multi-objective design optimization of expensive simulation models of antenna structures.

Design/methodology/approach

A deterministic algorithm for cost-efficient multi-objective optimization of antenna structures has been assessed. The algorithm constructs a patch connecting extreme Pareto-optimal designs (obtained by means of separate single-objective optimization runs). Its performance (both cost- and quality-wise) depends on the dimensions of the so-called patch, an elementary region being relocated in the course of the optimization process. The cost/performance trade-offs are studied using two examples of ultra-wideband antenna structures and the optimization results are compared to draw conclusions concerning the algorithm robustness and determine the most advantageous control parameter setups.

Findings

The obtained results indicate that the investigated algorithm is very robust, i.e. its performance is weakly dependent on the control parameters setup. At the same time, it is found that the most suitable setups are those that ensure low computational cost, specifically non-uniform ones generated on the basis of sensitivity analysis.

Research limitations/implications

The study provides recommendations for control parameter setup of deterministic multi-objective optimization procedure for computationally efficient design of antenna structures. This is the first study of this kind for this particular design procedure, which confirms its robustness and determines the most suitable arrangement of the control parameters. Consequently, the presented results permit full automation of the surrogate-assisted multi-objective antenna optimization process while ensuring its lowest possible computational cost.

Originality/value

The work is the first comprehensive validation of the sequential domain patching algorithm under various scenarios of its control parameter setup. The considered design procedure along with the recommended parameter arrangement is a robust and computationally efficient tool for fully automated multi-objective optimization of expensive simulation models of contemporary antenna structures.

Details

Engineering Computations, vol. 34 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 28 November 2018

Qigao Fan, Jie Jia, Peng Pan, Hai Zhang and Yan Sun

The purpose of this paper is to relate to the real-time navigation and tracking of pedestrians in a closed environment. To restrain accumulated error of low-cost…

Abstract

Purpose

The purpose of this paper is to relate to the real-time navigation and tracking of pedestrians in a closed environment. To restrain accumulated error of low-cost microelectromechanical system inertial navigation system and adapt to the real-time navigation of pedestrians at different speeds, the authors proposed an improved inertial navigation system (INS)/pedestrian dead reckoning (PDR)/ultra wideband (UWB) integrated positioning method for indoor foot-mounted pedestrians.

Design/methodology/approach

This paper proposes a self-adaptive integrated positioning algorithm that can recognize multi-gait and realize a high accurate pedestrian multi-gait indoor positioning. First, the corresponding gait method is used to detect different gaits of pedestrians at different velocities; second, the INS/PDR/UWB integrated system is used to get the positioning information. Thus, the INS/UWB integrated system is used when the pedestrian moves at normal speed; the PDR/UWB integrated system is used when the pedestrian moves at rapid speed. Finally, the adaptive Kalman filter correction method is adopted to modify system errors and improve the positioning performance of integrated system.

Findings

The algorithm presented in this paper improves performance of indoor pedestrian integrated positioning system from three aspects: in the view of different pedestrian gaits at different speeds, the zero velocity detection and stride frequency detection are adopted on the integrated positioning system. Further, the accuracy of inertial positioning systems can be improved; the attitude fusion filter is used to obtain the optimal quaternion and improve the accuracy of INS positioning system and PDR positioning system; because of the errors of adaptive integrated positioning system, the adaptive filter is proposed to correct errors and improve integrated positioning accuracy and stability. The adaptive filtering algorithm can effectively restrain the divergence problem caused by outliers. Compared to the KF algorithm, AKF algorithm can better improve the fault tolerance and precision of integrated positioning system.

Originality/value

The INS/PDR/UWB integrated system is built to track pedestrian position and attitude. Finally, an adaptive Kalman filter is used to improve the accuracy and stability of integrated positioning system.

Article
Publication date: 3 January 2017

Sai Krishna Kondoju and V.V. Mani

This paper aims to the increasing need for high-speed low-power data transmissions over frequency-selective fading channels has drawn attention to suggest dual-carrier…

Abstract

Purpose

This paper aims to the increasing need for high-speed low-power data transmissions over frequency-selective fading channels has drawn attention to suggest dual-carrier modulation (DCM) for multiband orthogonal frequency division multiplexing (OFDM) transceivers for ultra wideband (UWB) wireless personal area network (WPAN).

Design/methodology/approach

Under frequency-selective fading channel conditions, the decoder is not sufficient enough to decode the transmission bits of severely attenuated data tones. Hence, the authors suggest DCM for a multiband OFDM transceiver because of its multiple capability of providing both frequency diversity and coding gain. It also resulted in low bit-error-rate (BER) at a given signal- to-noise ratio when compared to conventional multiband OFDM system. To achieve an optimised BER, DCM transforms four re-ordered bits into two quaternary phase shift keying symbols and further transforms to two 16-quadrature amplitude modulation-like (16-QAM) symbols with a suitable mapping technique, and at the receiver end, they are decoded with maximum likelihood decision rule. After performing the transformation, the outage probability and average BER expressions are derived to analyse the system performance.

Findings

DCM is suitable for high data rate transmission and is immune to frequency-selective fading. The outage and BER performance outstands over conventional multiband OFDM transceiver because of the inclusion of DCM mapping.

Practical implications

It is widely used in WPANs such as high definition multimedia interface and wireless universal serial bus.

Originality/value

This paper derives novel closed-form outage probability and a tight upper bound on average BER expressions for DCM-based multiband OFDM UWB transceiver over frequency-selective Nakagami-m fading channels for any arbitrary value of m. For this, moment-generating function of sum of squared, independent and identically distributed (i.i.d.) Nakagami-m random variables are used. Further, the system performance is also validated for the case of exponential decaying power delay profile, and the simulation results are provided to check the accuracy of the derived expressions.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of 166