Thelaha Masri

Left Handed Metamaterial Design for Microstrip Antenna Application

This paper describes the design and simulation of the left-handed metamaterial structure incorporated with a single microstrip patch antenna. The combination of the modified square rectangular split ring (SRR) and the capacitance loaded strip (CLS) was used to obtain the negative value of permeability, mur and the negative permittivity, epsivr. From the simulation done, the gain of the antenna has been increased up to 4 dB. This had proven that the LH MTM can enhance the gain of the antenna.

Microstrip Patch Antenna Array at 5.8 GHz for Point to Point Communication

This paper described the design of microstrip patch array antenna with operating frequency at 5.8GHz for point to point communication. The array of four microstrip rectangular patch antennas with inset feed based on quarter-wave impedance matching technique were designed, simulated, fabricated and measured with the aid of microwave office software. The simulation and measurement result met the IEEE 802.11a standard and able to operate in upper UNII band for point to point communication. The 4times4 array has a return loss of -30.42 dB with 15% bandwidth. The gain obtained from simulation is 16 dB with 9deg half power beamwidth (HPBW)

A dual band gap slotted patch electromagnetic band gap for dual band microstrip antenna

This paper described the design of the dual band gap slotted patch EBG structure. By introducing double L slot into each EBG patch, a smaller rectangular patch has been introduced in each EBG patch resulting to the achievement of the second stop band frequency. The comparison between mushroom EBG structures has been investigated. The parametric study has been done involve the analysis of patch width effect of EBG and gap effects between elements in the EBG. The operating frequencies are 2.4 GHz ISM and 5.8 GHz UNI band. The slotted patch EBG structure and mushroom EBG structure have been simulated by using 3D simulation CST software. The design is based on FR4 board with has relative permittivity 4.7 and tangent loss 0.019.

Planar Dipole Antenna with and without Circular Parasitic Element

This paper describe the design of planar dipole antenna with circular parasitic element. The comparison between the planar dipole antenna with and without parasitic element has been presented followed by a discussion of the design. The simulation process was carried out using microwave office and CST software. These antennas were fabricated using inexpensive Fire Retardant-4 (FR4) board, using wet etching techniques. The S11 result shows the operating frequency is between 2.08 GHz and 3.48 GHz for planar dipole antenna with parasitic element. For planar dipole antenna without parasitic element, two ranges of operating frequency is between and 2.1 GHz and 3.08 GHz and another one operational frequency was found at 4.04 GHz and 4.98 GHz.

Analysis of Fractal Koch Dipole Antenna for UHF band application

The fractal Koch curve is certainly one of the most popular and well known fractals. This paper discussed the analysis of the fractal Koch dipole array antenna (FKDA). The primary goals of this project is to proof of the concept of fractal Koch dipole array using log periodic technique to reduce the antenna size. This antenna is operating at ultra high frequency (UHF) band frequency from 300 MHz to 3 GHz. The analysis is based on the number of elements, degree of flare angle, current distribution, radiation pattern and gain of the antennas. The antenna has been simulated using Computer Simulation Technology CST 2008. The performance of the antennas has been observe and discussed in this paper.

Antenna array at 2.4 GHz for wireless LAN system using point to point communication

This paper described the design of microstrip patch antenna array operating at 2.4 GHz for Wireless Video using point to point communication system. The array of four by four microstrip square patch antennas with inset feed technique were designed, simulated, fabricated and measured with the aid of microwave office software. The simulation and measurement results are able to operate in ISM band for point to point communication system. The four by four arrays had a return loss of -8 dB with 16% bandwidth. The gain obtained from measurement is 14 dBi with 30deg half power beamwidth (HPBW) for H plane and 28deg for E Plane.

Electromagnetic Band Gap Structure for Planar Ultra Wide Band Antenna

An innovative technique involving the usage of a mushroom Electromagnetic Band Gap (mEBG) structure with an ultra wideband (UWB) antenna is reported in this work. A single unit of mEBG lattice is incorporated within a novel UWB antenna to perform the band rejection operation. The antenna can be fixed to reject or reduce the transmit power for any band within the UWB spectrums of frequencies through a careful design of this mEBG structure, thus solving the problems concerning interference and reducing the requirements for complex filtering electronics within the UWB devices.

Microstrip antenna incorporated with left-handed metamaterial at 2.7 GHz

The scope of this project was to design and simulate left-handed metamaterial structure incorporated with a single microstrip patch antenna at 2.7 GHz. The combination of the modified square rectangular split ring (SRR) and the capacitance loaded strip (CLS) was used to obtain the negative value of permeability, μ and the negative permittivity, ε. From the simulation and fabrication done, the gain of the antenna has been increased up to 4 dB. This had proven that the LH MTM can enhance the gain of the antenna.

Circular Polarization Array Antenna

A 4 by 4 circular polarization microstrip square patch array antennas based on quarter-wave impedance matching and T-junction power divider were designed, simulated, fabricated and measured. The patch type used to generate circular polarization is corner-truncated square microstrip antenna. All the designs met the WLAN circular polarization point to point application set by IEEE802.11b standard and operates in ISM band at 2.4 GHz. Analysis shows that larger arrays provide better return loss, more bandwidth, smaller beam width and higher gain comparing with single element antenna as a reference. A 4 by 4 circular polarization square patch arrays have a side lobe IEEE802.11b standardes. This is due to mutual coupling effects occurred in arrays. All the measurement results show a good return loss more than -15dB. These indicate a good impedance matching is achieved in designing the patches and feeds.

Dual band Electromagnetic Band Gap (EBG) structure

In this paper, a 3 by 3 dual band electromagnetic band gap (EBG) structure has been designed to cover the two frequency of unlicensed Band at 2.4 GHz and 5.2 GHz. The characteristic of the EBG structure is investigated by measuring the forward transmission coefficient, S21. The discussion of the design and the evaluation of the structure itself have been made. The simulation process was carried out using microwave office software. This structure has been designed using 1.6 mm Fire Retardant-4 (FR4) board which has relative permittivity of 4.9 and loss tangent of 0.019. The simulated result for S21 shows the band gap frequencies measured are found to be between 2.037 GHz and 2.609 GHz with cover 2.4 GHz ISM band GHz and between 4.738 GHz and 5.492 GHz which cover 5.2 GHz UNI band.