Design and analysis of various types of Micro Strip Antennas Under esteemed guidence of Mr.J.Lakshmi Narayana M.Tech,Ph.DD.L.Pavan kumarJ.AnushaB.ManikantaK.Vidya raniM.Sampath kumar
Introduction to Micro Strip Antennas In genaral Micro strip antennas are also known as “ PRINTED ANTENNAS ”. These are mostly used at microwave frequencies Because the size of the antenna is directly tied the wavelength at the resonant frequency. Micro strip patch antenna or patch antenna is a narrowband wide-beam antenna. The patch usually fed along the centerline to symmetry and thus minimize exitation of undesirable modes.
Micro strip antennas are easy to fabricate and comfortable on curved surface . The directivity is fairly insensitive to the substrate thickness. Micro strip patch antennas patches are in variety of shapes , such as rectangular , square , triangular and circulator
Aim: The design and analysis of various micro strip patch antennas such as rectangular ,square ,circular and arrays are proposed in this project . An artificial neural network model are to be developed for proposed micro strip antennas . A comparative study on the performance of various micro strip antennas i.e between square , circular,rectangular antennas are observed.
Substrates are: The most commonly used substrates are, 1) Honey comb(dielectric constant=1.07) 2)Duroid(dielectric constant=2.32) 3)Quartz(dielectric constant=3.8) 4)Alumina(dielectric constant=10) A thicker substrate will increase the radiation power , reduce conductor loss and improve Band width.
Among all the feeds most prefarable oneis coaxial feed.Because impedence matching is achivedthrough this feed .This feed is using huygen’s principlemodeled by cylindrical band of electriccurrent.
Comparision of various types of flatprofile printed antennas:Charaterstics Microstrip patch Microstrip slot Printed diploe antenna antenna antennaProfile Thin Thin ThinFabrication Very easy Easy EasyPolarization Both linear& Both linear& Linear circular circularDual freq Possible Possible PossibleoperationShape Any shape Rec &circle Rec &tiangularSpurious radiation Exists Exists exists
Softwares used: For design and simulation we are using ‘MAT LAB’ software For analysis we are using the ‘SONET’ and ‘AN- SOFTWARE. For artificial neural networks model we are using the different simulation softwares.
Advantages: Easy to fabricate on curved surfaces Easily integrated Dual frequency and dual polarization can be easily made. Linear and circular polarization is possible Low cost , Less size Can be integrated in microwave circuits
Disadvantages: Narrow bandwidth associated with Tollerence problem Lower gain(nearly 6db) Large ohmic losses in feed structure of arrays Exitation of surface waves Most microstrip antetnnas radiate into half-space
Remedies: Low power and low gain can overcome by arrays configuration. Surface wave associated limitations such as poor efficiency,increased mutual coupling,reduced gain and radiation pattern can overcome. The band width can increase upto 60% by using some special techniques.
Applications: Used in mobile satellite communication system. Direct broad cast telivision(DBS). Wire less LAN’S. Feed elements in coaxial system GPS system. Missiles and telementry