Now showing 1 - 5 of 5
  • Publication
    Compact low pass filter with deep and wide stopband using H-shaped defected microstrip structure
    A deep attenuation level and wide stopband bandwidth, sharp roll-off and low insertion loss in the passband using H-shaped defected microstrip structure (DMS) at open circuit stub resonator (OCSR) of the stepped-impedance low pass filter (SILPF) is presented in this paper. The proposed filter consists of H-shaped that is etching at the microstrip line of OCSR. The OCSR is embedded in the middle of high impedance line of the SILPF. The effect of the applying H-shaped DMS is investigated through parametric studies by comparing H-shaped with Y-shaped and U-shaped. It is observed that the comparison with conventional SILPF shows that the proposed modification filter exhibit a deep and large rejected band of 27 dB attenuation level from 8.21 GHz to 23.16 GHz up to 3 fc. The proposed filter also offers sharp roll-off at 7.31 GHz cut-off frequency and maximum ripple value in the range of DC to 6 GHz is less than 0.35 dB.
  • Publication
    Tuneable dual-mode narrowband bandstop filter using loaded microstrip resonator
    Novel tuneable dual-mode narrowband bandstop filter using loaded microstrip resonator is presented. The filter is designed by using coupled line coupling with the microstrip resonator. There is two different pair of loaded resonator that produces a dual band bandstop filter. The dual band bandstop resonance frequency can be tuned independently by adjusting the resonator width and length. To achieve high selectivity of the bandstop filter response, defected ground structure (DGS) is applied in the filter layout. The tapped lines structure (TLS) are used to suppress second harmonic frequency. The dual band bandstop filter is resonant at 2.4 GHz with 200 MHz of bandwidth and 5.8 GHz with 300 MHz of bandwidth. The bandstop filter layout is fabricated on RO 4003C with 0.508 mm of substrate thickness. It is compact dimension with 19.6mm × 38.8mm. The advantages of this bandstop filter are simple layout and it can be tuned to the specified frequencies.
  • Publication
    SWIPT in Rician MIMO Interference Channels with Spatial Antenna Correlation
    In this paper, we investigate simultaneous wireless information and power transfer (SWIPT) under spatial correlation in multiuser multiple-input-multiple-output (MU-MIMO) fading channels where the line-of-sight (LOS) path between the transmitter and the receiver is present. While the energy receiving terminals are harvesting energy, the information receiving terminals are receiving their desired signal-to-interference-plus-noise ratio (SINR) under the total power constraint at the transmitting terminal of the proposed SWIPT system. We use the Kronecker model to study the impact of MIMO antenna correlation and the Rician K-factor as the main parameter to set up the different fading conditions. We use semi-definite programming (SDP) to formulate the proposed SWIPT system. Our numerical results confirm that the performance of the proposed design improves in the absence of LOS component, i.e., with a zero K-factor or pure Rayleigh fading channel, and deteriorates as the LOS channel component grows. We show that the total harvested energy monotonically decreases as the Rician K-factor increases.
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  • Publication
    Optimization of Beamforming Matrix Design for Multi-Cell MIMO with SWIPT Systems
    Energy harvesting is emerging as a promising new solution to provide continuous energy supplies to wireless rechargeable devices. This paper investigates wireless information and energy transfer in multi-cell multiple-input-multiple-output (MIMO) systems. An optimisation problem that designs the beamforming matrix is introduced to maximise the sum of total harvested energy collected from all energy receiving terminals while guaranteeing the desired data rate for each information receiving terminal remains above a certain level. Total power constraint at each transmitting terminal that was generated from the renewable energy and purchased from the grid is also considered. The channel capacity that requires the use of slower and less reliable CVX's successive approximation heuristic is formulated, and then, the non-convex problem is transformed into a convex problem form modelled by a semidefinite relaxation (SDR). The results show the effectiveness of the multiple antennas used in all cells provide better performance and also maximise the total harvested energy at all energy receiving terminals.
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  • Publication
    Parametric analysis on the effect of open circuit stub resonator towards the performance of ultra-wideband stepped impedance low pass filter
    This paper presents the parametric studies on the effect of open circuit stub resonator (OCSR) towards the performance of Chebyshev Ultra-Wideband Stepped Impedance Low Pass Filter (SILPF). The SILPF is realized by loading OCSR to the high impedance line of the main design in order to overcome the drawback of conventional SILPF. The filter can produce sharp transition band and also wide stopband bandwidth. The design of SILPF is based on 5th order Chebyshev with 0.1 dB ripple. The filter is designed to operate at cut-off frequency 7.30 GHz. By investigating the effect of varying dimension of OSCR’s selected parameters, this paper is able to highlight the susceptibility of modifying cut-off frequency, fc and also transmission zeroes frequency, fz in order to be used for different applications. Thus, the combination of SILPF and OCSR and also rectangular patch combined feed-line structure exhibits wide rejection bandwidth better than −20 dB from 8.20 GHz up to 23.38 GHz. The filter design is simulated on Roger 4003 with relative dielectric constant, εr of 3.38 and also the substrate thickness, h of 0.508. This proposed simulated filter design has shown promising result and could be further analyzed for experimental works and fabrication. Therefore, the filter is beneficial for communication and radar systems particularly to avoid the interference and harmonic as well as the spurious response signals.