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All Journal Bulletin of Electrical Engineering and Informatics Bulletin of Electrical Engineering and Informatics Bulletin of Electrical Engineering and Informatics Indonesian Journal of Electrical Engineering and Computer Science
Azremi Abdullah Al-Hadi
Universiti Malaysia Perlis
Computer Science & IT Electrical & Electronics Engineering Engineering

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Performance evaluation of 2-port MIMO LTE-U terminal antenna with user’s hand effect Ahmed Mohamed Elshirkasi; Azremi Abdullah Al-Hadi; Rizwan Khan; Ping Jack Soh
Bulletin of Electrical Engineering and Informatics Vol 8, No 1: March 2019
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1325.929 KB) | DOI: 10.11591/eei.v8i1.1408

Abstract

This paper presents the performance evaluation of 2-port MIMO antenna for LTE-U sub 6 GHz band. The evaluation focuses on the effect of user’s hand in a uniform environment and the analysis were carried out on simulation and measurement data of antenna ports. Results show that the highest performance of the design is on the frequency range from 4.5 GHz to 5.5 GHz, and the ports have low envelope correlation coefficient (ECC) less than 0.16 in both cases of without and with user’s hand. However, the presence of the user’s hand reduces mean effective gain (MEG) of ports and diversity combining gain by more than 1.6 dB compared with no-hand case. The multiplexing efficiency is around 81% and reduced by the presence of the user’s hand to 55%. Despite this reduction; the design shows high spatial multiplexing capability in both cases. The capacity carried by the second transmission eigenmode is about 39% from the total capacity under water-filling algorithm transmit power allocation.
User’s hand effect on efficiency of 2-port 5 GHZ mobile terminal antennas Che Muhammad Nor Che Isa; Azremi Abdullah Al-Hadi; Saidatul Norlyana Azemi; Rizwan Khan
Bulletin of Electrical Engineering and Informatics Vol 8, No 2: June 2019
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (745.513 KB) | DOI: 10.11591/eei.v8i2.1425

Abstract

In this paper, the influence of user’s hand on mobile terminal antenna when it placed approximately on top of Multiple Input Multiple Output radiating element antennas (PIFAs) is studied extensively. The antenna is designed to operate at 5 GHz with 1.5 GHz of -6 dB bandwidth. The effect of user’s hand with different finger positions are studied at seven positions on slit at the ground plane, seven differences height above the antenna and nine different locations around the radiating element at 2 mm height from antenna. The losses due to presence of hand are studied in terms of scattering parameters, radiation efficiency and matching efficiency. The maximum loss in term of isolation in the presence of user’s hand is found at 6 mm on the slit and it decreased as the hand move away from the slitted area on the ground plane. The maximum efficiency loss is observed when the finger is placed right on top of the radiating element with -5.85 dB compare to antenna without the presence of user’s hand. On the other hand, the result for matching efficiency indicates approximately 0.2 dB losses occurred when the fingers are varied at different height and position.
Structural Health Monitoring Sensor based on A Flexible Microstrip Patch Antenna Hamse Abdillahi Haji Omer; Saidatul Norlyana Azemi; Azremi Abdullah Al-Hadi; Ping Jack Soh; Mohd Faizal Jamlos
Indonesian Journal of Electrical Engineering and Computer Science Vol 10, No 3: June 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v10.i3.pp917-924

Abstract

A microstrip patch antenna strain sensor operating at dual frequencies 1.8GHz and 2.4GHz have been designed based on the relation between the resonant frequency and the strain applied to it. Felt substrate with a height of 3mm and dielectric constant of 1.44 and shield conductor are used for the design of this antenna. Testing results show that the resonant frequency of the microstrip patch antenna is 1.78 GHz and 2.4 GHz, which agrees with the simulation. The resonant frequency of the microstrip patch antenna increases linearly with the increase of the applied strain. This microstrip patch antenna strain sensor can be integrated with other components easily and have a great potential applications in structural health monitoring systems.
Co-Authors Ahmed Mohamed Elshirkasi Che Muhammad Nor Che Isa Hamse Abdillahi Haji Omer Mohd Faizal Jamlos Nur Basyirah A. Rahman Ping Jack Soh Rizwan Khan Saidatul Norlyana Azemi Wai Loon Cheor