Md. Azad Hossain

Design and parametric analysis of a planar array antenna for circular polarization

A new circularly polarized planar array antenna using linearly polarized microstrip patches is designed and optimized for X-band wireless communication applications. Four square patch elements with feed network are used to design the circularly polarized array antenna. The feed network consists of microstrip lines on the obverse side of the dielectric substrate and slot line on the reverse side of the substrate. Both-sided MIC technology is successfully employed to apply its inherent advantages in the design process of the array structure. The unequal feed line is used to create 90° phase difference between the linearly polarized patches. Therefore, the circular polarization is realized by the combination of linearly polarized patches and unequal feed line. Characteristics of the proposed array are investigated by using two electromagnetic (EM) simulators: advanced design system and EMPro. The −10 dB impedance bandwidth of the antenna is around 5%. The 3 dB axial ratio bandwidth of 1.48% is obtained. The design of the proposed antenna along with parametric study is presented and discussed.

Design of a circular polarization array antenna with dual-orthogonal feed circuit

In this paper, the design of a circularly polarized array antenna at 10 GHz frequency is presented. The proposed antenna consists of a 1×2 array antenna with feed circuit. To realize circular polarization, dual-orthogonal feed circuit is used that excites two orthogonal modes with equal amplitude but quadrature in phase. Feed circuit is designed using microstrip lines and slot lines where microstrip lines are placed on the top surface of the substrate and slot lines on the reverse side of the substrate. The feed point is chosen in such a way that it provides the each patch element two RF signals with 90° phase difference. Therefore, the circular polarization is realized by employing microstrip-slot feed circuit. “Both-Sided MIC Technology” is used to design the proposed array antenna as it gives flexibility in the design process. The simulated return loss of the proposed array antenna is less than -45 dB at the design frequency. The 3 dB axial ratio bandwidth of 0.8% is obtained. The structure and the basic behavior along with the simulation results of the proposed circularly polarized array antenna are demonstrated in this paper.

Design of a dual circular polarization microstrip patch array antenna

Design of a microstrip array antenna to achieve dual circular polarization is proposed in this paper. The proposed antenna is a 2×2 array antenna where each patch element is circularly polarized. The feed network has microstrip lines, cross slot lines and air-bridges. The array antenna can excite both right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP) without using any 90° hybrid circuit or PIN diode. “Both-sided MIC Technology” is used to design the feed network as it provides flexibility to place several types of transmission lines on both sides of the dielectric substrate. The design frequency of the proposed array antenna is 10 GHz. The simulated return loss exhibits an impedance bandwidth of greater than 5% and the 3-dB axial ratio bandwidths for both RHCP and LHCP are approximately 1.39%. The structure and the basic operation along with the simulation results of the proposed dual circularly polarized array antenna are demonstrated in this paper.

Design of a circular polarization array antenna using triple feed structure

This paper describes an effort to design and characterize a patch antenna with circular polarization by using a single feeding technique instead of multiple feeding or any switching devices or couplers. Here a single feed is split into three feed lines to ensure orthogonal modes on each radiating patches. Both-sided MIC technology is used to realize the proposed array antenna. The proposed antenna consists of 4 patch elements and microstrip feed lines on the obverse side of the Teflon dielectric substrate. The ground plane and the slot lines are on the reverse side of the substrate. The dielectric constant er is 2.15. The antenna is able to radiate at 10 GHz (X band) which is demonstrated and verified through proper simulation technique.

Design of a circular polarization array antenna using linear polarization patches

This paper presents a new circularly polarized array antenna using linearly polarized microstrip patches with a gain of 7.47 dBi. The array structure consists of four square patch antennas with feed network. The feed network is designed using microstrip lines on the obverse side of the dielectric substrate and slot line on the reverse side of the substrate. The Teflon glass fiber substrate is used with a permittivity of 2.15. The design frequency of the proposed array antenna is 10 GHz where simulated return loss is less than -45dB. The unequal feed line is used in order to realize 90° phase difference between the linearly polarized patches. Therefore, the circular polarization is realized by the combination of linearly polarized patches and unequal feed line. Advanced Design Systems (ADS) by Agilent Technologies is used for the simulation of the proposed array antenna.

Design of an x-band microstrip array antenna for circular polarization

In this paper, the design of a circularly polarized array antenna with 9.56 dBi of gain at 10 GHz frequency is presented. The proposed antenna consists of a 2×2 array antenna with feed network where all microstrip patches are linearly polarized. “Both-Sided MIC Technology” is used to design the proposed array antenna. The simulated return loss of the proposed array antenna is less than -35dB. The 3 dB axial ratio bandwidth of 2.21% is obtained. The unequal feed line is used in order to realize 90° phase difference between the linearly polarized patches. Therefore, the circular polarization is realized by the combination of linearly polarized patches and unequal feed line. The structure and the basic behavior along with the simulation results of the proposed linearly polarized array antenna are demonstrated in this paper.

Wheel therapy chair: A smart system for disabled person with therapy facility

Each and every person in this world has a desire to live a normal human life but accidents, diseases, elder-ship make their desire into disability. Moreover, there are lots of handicaps and elders as well as the number of paralyzed people are increasing day by day. They always need another person in moving and have to go under some physical therapies under the guidance of a therapist to recuperate their strain back. In this paper the proposed system helps them to move freely & safely and also takes the activities of a therapist in a cost effective manner. This system is a combination of different controlling features, has the ability to detect obstacle and provides few kinds of therapies. A smart wheelchair is developed by using voice recognition system to control the movement of wheelchair and also with Arduino interfaced joystick. Besides, an ultrasound system provides the facility of automatic obstacle detection. The aim of research is to compact many facilities in a single wheelchair at low cost.

Design of an orthogonal feed circularly polarized microstrip array antenna suitable for large scale extensible arrays

This paper presents a circularly polarized 1×2 array antenna for X-band applications. Both-sided MIC technology is effectively used to design this array antenna as the array antenna consists of both microstrip lines and slot lines to realize the feed network. Patch elements and microstrip lines are placed on the top surface of the substrate and slot lines on the reverse surface (ground plan) of the substrate. Each of the patches is excited by two orthogonal feed lines. One of the feed lines is ahead by an odd multiple of quarter wavelength than the other feed line. This strategy makes the each patch circularly polarized. The impedance bandwidth is about 630 MHz and the 3-dB axial ratio bandwidth is more than 1%. This array antenna is very suitable to make large scale extensible array antennas by using it as a unit array.