M. N. Salimi

Dual frequencies of half-monopole antenna for WiMAX and Wi-Fi application

This paper discuss about designing a dual frequencies monopole antenna with side feed. The antenna is required to operate at a frequency of 2.3 GHz and 2.45 GHz simultaneously. This proposed antenna is designed based on T-Slot antenna. With combination of stub at the left, it is observed that the capabilities of dual band frequencies have been successfully achieved. Moreover, HPBW of 160.3° with gain of 2.12 dB extends its capability in providing a wider coverage for Wimax and Wi-Fi applications.

2.3 GHz – 2.45 GHz circular polarization U-slot patch antenna

A single-coaxial feed circularly polarized (CP) patch antenna is designed using the U-slot patch technique. With the presence of U-slot, the antenna patch on 3 layers of FR-4 substrate (dielectric constant = 4.7), is able to cover the range of frequency of 2.28 to 2.58 GHz. The size of patch 0.21λ X 0.21λ, while the ground is 0.39λ X 0.39λ, and the thickness of substrate is 0.038λ. The measured gain is 4.232dBi and S11 bandwidth is about 300 kHz. The proposed antenna is suited for the Wimax and Wi-Fi application.

Effects of parasitic ring on the performance of an elliptical shaped antenna

This paper introduces the performance of an elliptical shaped antenna with random slots with the use of parasitic element and compares the results between the original patch and the patch with parasitic ring mounted on foam. 5.8GHz is the reference or desired frequency set for measuring the performance of this antenna. The purpose of using parasitic element is to optimize the gain and radiation efficiency of this antenna since microstrip antennas has weaknesses in gain and efficiency. Three elliptical shaped slots with different dimensions are designed and connected to each other to allow equal surface current distribution throughout the radiating patch. In addition, 14 cylindrical dots with different radius were designed at the left most center of the patch, making it as a part of the antenna. The parasitic ring element will be supported by 2 different forms of substrate which is foam and a high dielectric constant material. However it is tested one at a time. Adopting the parasitic element method has provided outstanding effects on the antennas gain and efficiency. The antenna manages to radiate a maximum gain of 4.714dB. The radiation efficiency and total efficiency of the antenna has improved significantly with the usage of parasitic ring. The proposed antenna can be used for point to point communication and other applications under the same frequency range if the research done is considered successful.

Elliptical shape microstrip patch antenna without dots

This paper introduces the performance of an elliptical shaped antenna with random slots and compares the results between the original patch and the patch without dots. 5.8GHz is the reference or desired frequency set for measuring the performance of this antenna. For the design, three elliptical shaped slots with different dimensions are deployed and connected to each other acting as a main radiating element with coaxial feeding as the excitation method. While, 14 cylindrical dots with different radius are positioned at the left most center of the smallest elliptical slot. An additional slot is created for the coaxial feed point at the center of the radiating patch to allow equal surface current distribution. The antenna is capable of functioning with a maximum directivity of 6.948dBi with a return loss of -22.87dB. Moreover, the proposed antenna radiates in an elliptical polarization pattern where the axial ratio measured is more than 1. The antenna is proficient to be applied in modern communication systems especially point to point communication where it functions at the same bandwidth range.

2.45 GHz of elliptical shape patch antenna

This paper describes the design of multiple element of co-polarization elliptical patch antenna operating at 2.45GHz. Computer Simulation Technology (CST) Microwave Studio is used as an effective tool for 3D electromagnetic simulation of high frequency design. In this paper, different dimensions with three elliptical shaped slots are implemented and attached with main radiating element while power has been excited from coaxial feeding. Radius of 14 different cylindrical dots are located at the left most center of the smallest elliptical slot. The analysis on performance will be based on the obtained result especially in radiation pattern, bandwidth and return loss. The antenna is capable of functioning with a maximum directivity of 6.948dBi and a return loss of -22.87dB.

Dual-frequencies of co-polarization circular antenna for GPS and WiMax application with corporate feeding technique

A circular polarization corporate feed antenna with dual frequencies of 1.575 GHz and 2.3 GHz is presented in this research. The antenna consists of 2 circular radiating patches with the transmission line are divided into two branches. Two different circular patches are able to produce two different frequencies with circular polarization (CP) capacity. With gain of 4.108 dB and 4.23 dB, return loss of -11.58 dB and -18.34dB, the proposed antenna is fully capable to provide the coverage of GPS and WiMax application in the future.

Triple-frequencies of co-polarization Yagi Patch antenna for 2.3 GHz, 2.4 GHz & 5.8 GHz application

This paper presents a triple-frequencies of co-polarization Yagi Patch antenna dropped at desired frequency 2.3 GHz, 2.4 GHz and 5.8 GHz. Computer Simulation Technology (CST) Microwave Studio will be introduce as an effective tool for 3D electromagnetic simulation of high frequency components. The analysis on performance will be based on the obtained results especially in return loss, bandwidth, surface current and radiation pattern.

Effects of superstrate on the performance of an elliptical shaped antenna without dots

This paper introduces the performance of an elliptical shaped antenna with random slots with the use of superstrate and compares the results between the original patch and the patch with superstrate layer but without dots. 5.8GHz is the reference or desired frequency set for measuring the performance of this antenna. The purpose of using superstrate is to optimize the gain and radiation efficiency for this antenna since microstrip antennas have limitations in gain and efficiency. For the design, three elliptical shaped slots with different dimensions were implemented and are connected to each other to allow current flow via coaxial feeding. Furthermore, 14 cylindrical dots are placed at the left most center of the radiating patch, specifically at the slot with the smallest elliptical dimensions. The usage of a high dielectric constant substrate or superstrate has an outstanding effect on the antennas gain and efficiency. The antenna is capable of producing a maximum gain of 6.340dB with a very much enhanced radiation efficiency of 71.39% and total efficiency 66.61% without the presence of the dots. The presence of superstrate which is stacked above the antenna contributes to a much larger bandwidth of 204.1 MHz, making it applicable to 21st century communication systems. The absence of cylindrical dots from the antenna unexpectedly produces a spectacular range of bandwidth which shows the unpredictable results the dots can have on the radiating patch. The advance in gain and bandwidth makes the antenna a promising candidate to be applied in everyday communication systems and devices.

Foam ring on elliptical shaped antenna without dots element

This paper introduces the performance of an elliptical shaped antenna with random slots with the use of parasitic element and compares the results between the original patch and the patch without dots stacked with parasitic element mounted on foam. 5.8GHz is the reference or desired frequency set for measuring the performance of this antenna. The purpose of using parasitic element is to optimize the gain and radiation efficiency of this antenna since microstrip antennas has weaknesses in gain and efficiency. Three elliptical shaped slots with different dimensions are designed and connected to each other to allow equal surface current distribution throughout the radiating patch. In addition, 14 cylindrical dots with different radius were designed at the left most center of the patch, making it as a part of the antenna. Adopting the parasitic element method has provided outstanding effects on the antennas gain and efficiency. The antenna manages to radiate a maximum gain of 4.206dB. The radiation efficiency and total efficiency of the antenna has improved significantly with the usage of parasitic ring. The proposed antenna can be used for point to point communication and other applications under the same frequency range if the research done is considered successful.

The effects of parasitic superstrate elliptical shaped antenna without dots element

This paper introduces the performance of an elliptical shaped antenna with random slots with the use of parasitic element and compares the results between the original patch and the patch without dots stacked with parasitic element mounted on a high dielectric substrate. 5.8GHz is the reference or desired frequency set for measuring the performance of this antenna. The purpose of using parasitic element is to optimize the gain and radiation efficiency of this antenna since microstrip antennas has weaknesses in gain and efficiency. Three elliptical shaped slots with different dimensions are designed and connected to each other to allow equal surface current distribution throughout the radiating patch. In addition, 14 cylindrical dots with different radius were designed at the left most center of the patch, making it as a part of the antenna. The parasitic ring element will be supported by 2 different forms of substrate which is foam and a high dielectric constant material. However it is tested one at a time and for this paper, the high dielectric substrate is used. Adopting the parasitic element method has provided outstanding effects on the antennas gain and efficiency. The antenna manages to radiate a maximum gain of 5.801dB. The radiation efficiency and total efficiency of the antenna has improved significantly with the usage of parasitic ring. The proposed antenna can be used for point to point communication and other applications under the same frequency range if the research done is considered successful.