Design of miniaturized ultra ppt
- 1. DESIGN OF MINIATURIZED ULTRA- WIDEBAND CONICAL SPIRAL ANTENNA USING HFSS Under Guidance of T Anusha Lalitha Assistant Prof. TCE, BMSCE By Sandeep Kumar P 1BM11TE045 Satish Kumar T V 1BM11TE048 Sharath Chandran C K 1BM11TE406 Santosh Patil 1BM12TE409
- 2. Introduction • What is an ANTENNA ???
- 3. Antenna Characteristics An antenna is a device that is made to efficiently radiate and receive radiated electromagnetic waves. There are several important antenna characteristics that should be considered when choosing an antenna for your application as follows: • Antenna radiation patterns • Power Gain • Directivity • Polarization
- 4. Conical Spiral Antennas High data rate and wider bandwidth requirements for datavideo transfer and growth in number of users lead to increase operating frequencies of these systems to microwave and millimeter-wave frequencies. Spiral antennas are one of frequency independent antennas with wide bandwidth and good pattern efficiency in compare with other antennas. Desirable radiation characteristics can be achieved by changing circular radius r, number of turns N and the width of them W.
- 5. Types of conical spiral antenna Log Spiral Antenna Archimedean Spiral Antenna Sinuous Spiral Antenna
- 6. ConstructionofSpiralAntenna Creating First Arm The second arm is constructed by Rotating the first arm by π radians
- 7. Log Spiral Antenna Parameters Where ro = inner radius a = Ln( ExpansionRatio)/2pi The pitch angle Ψ related to expansion coefficient a by tan Ψ = r/(da/dΦ) = 1/a the design ratio τ is defined to be less than 1 and is given by this is ratio of OA/OB of the figure and is the ratio of the radii for one turn of the log spiral curve.
- 8. ConicalArchimedean Antenna Parameters The centerline of the antenna is defined by ρ = aφ The first arm, which begins along the x-axis in this example, is defined by the edges
- 9. ConicalSinuousAntenna Parameters where Φ and r are polar coordinates p is cell number and τ is growth rate the design parameters may be independent of p to form a LP structure that is periodic function of logarithm of radius r .
- 11. HFSS….??? Uses Finite Element Method to solve Electromagnetic structure Used for antenna design and design of complex RF electronic circuit elements including filters, transmission lines, etc. HFSS is essential for designing high-frequency and/or high-speed components used in modern electronics devices
- 12. Features Powerful drawing capabilities to simplify design entry Computes s-parameters and 3D passive structures Advanced materials Model Library-including spiral inductor Calculate far-field patterns Wideband fast frequency sweep Create parameterized cross section models- 2D models
- 13. HFSS Analysis Design Flowchart Construct Geometry (User Input) Define Volume Conditions (User Input) Define Surface Conditions (User Input) 2D Excitation Solution (Automatic) 3D Mesh Generation (AutomatIc) Solve 3D Matrix (Automatic) View/Plot S-Parameters (User Input) View/Plot Fields (User Input) PRE-PROCESSING SOLUTION POST-PROCESSING Define Solution Requirements (User Input)
- 14. Applications Antennas Microwave transitions Waveguide components RF filters Three-dimensional discontinuities Passive circuit elements
- 15. RESULTS
- 17. INPUT IMPEDENCE LOG SPIRAL ARCHIMEDEAN
- 18. Z PARAMETERS
- 19. 3D GAIN OF RHCP LOG SPIRAL ARCHIMEDEAN SINUOUS
- 20. 3D GAIN OF LHCP LOG SPIRAL ARCHIMEDEAN SINUOUS
- 21. 2D GAIN OF RHCP LOG SPIRAL ARCHIMEDEAN
- 22. SINUOUS SPIRAL
- 23. 2D GAIN IN LHCP LOG SPIRAL ARCHIMEDEAN
- 24. SINUOUS
- 25. Features of Conical Spiral Antenna • Conical spiral antennas are true frequency independent antennas Cover the required 6.5 : 1 frequency range • Relatively constant beam characteristics (beamwidth, polarization, ...) • Usefully wide beamwidth while maintaining other desirable properties • Low ellipticity (axial ratio) • Good polarization purity (wide band) • Low mutual coupling in array
- 26. In additionto the aboveperformance requirements,the antennawouldbe versatile in the followingways: • Inexpensive • High power levels (100 W) as sensor • CW and Pulse Applications • Use in confined spaces • Provides Circular Polarization
- 27. Antenna characteristics with frequency • Nearly constant beam pattern • Low back-lobe at all but lowest frequency • Relatively small, smooth impedance variation • Good axial ratio maintained • Spiral features 1. Low mutual coupling 2. Polarisation purity 3. Good isolation
- 28. Applications • Measurement of electromagnetic (EM) Shielding Effectiveness in confined spaces. • As facility-embedded EM sensors for receive antennas. • Wideband communications. • Monitoring of the frequency spectrum.
- 29. Applications(contd.) • A pair of spiral antennas are used in this application, having identical parameters except the polarization, which is opposite (one is right-hand, the other left-hand oriented). • Spiral antennas are useful for microwave direction-finding.
- 30. CONCLUSION : The main goal is to UWB conical log spiral antenna is to transmit data at very high data rates by sending pulses of energy rather than using a narrow band frequency carrier. The main objective was to get information of the near- and far-field characteristics and on the input impedance for a wide range of parameters is presented in a form suitable for use in the design of practical antennas.