Reconfigurable antenna

Abstract: Microstrip Radiators: Various Microstrip Antenna Configurations. Feeding Techniques and Modeling. Applications. Radiation Field. Surface Waves and Photonic Band-Gap Structures. Analytical Models for Microstrip Antennas: Transmission Line Model. Cavity Model. Generalized Cavity Model. Multi-port Network Model (MNM). Radiation Fields. Aperture Admittance. Mutual Admittance. Model for Coaxial Probe in Microstrip Antennas. Comparison of Analytical Models. Full-Wave Analysis of Microstrip Antennas: Spectral Domain Full-Wave Analysis. Mixed-Potential Integral Equation Analysis. Finite-Difference Time Domain Analysis.Rectangular Microstrip Antenna: Models for Rectangular Patch Antenna. Design Considerations for Rectangular Patch Antennas. Tolerance Analysis of Rectangular Microstrip Antennas. Mechanical Tuning of Patch Antennas. Quarter-wave Rectangular Patch Antenna. Circular Disk and Ring Antennas: Analysis of a Circular Disk Microstrip Antenna. Design Considerations for Circular Disk Antennas. Semicircular Disk and Circular Sector Microstrip Antennas. Comparison Of Rectangular And Circular Disk Microstrip Antennas. Circular Ring or Annular Ring Microstrip Antenna. Circular Sector Microstrip Ring Antenna. Microstrip Ring Antennas of Non-Circular Shapes. Dipoles and Triangular Patch Antennas: Microstrip Dipole and Center-Fed Dipoles. Triangular Microstrip Patch Antenna. Design of an Equilateral Triangular Patch Antenna. Microstrip Slot Antennas: Microstrip-Fed Rectangular Slot Antennas. CPW-Fed Slot Antennas. Annular Slot Antennas. Tapered Slot Antennas (TSA). Comparison of Slot Antennas with Microstrip Antennas. Circularly Polarized Microstrip Antennas and Techniques: Various Types of Circularly Polarized Microstrip Antennas. Singly-Fed Circularly Polarized Microstrip Antennas. Dual-Orthagonal Feed Circularly Polarized Microstrip Antennas. Circularly Polarized Traveling-Wave Microstrip-Line Arrays. Bandwidth Enhancement Techniques. Sequentially Rotated Arrays. Broad-Banding of Microstrip Antennas: Effect of Substrate Parameters on Bandwidth. Selection of Suitable Patch Shape. Selection of Suitable Feeding Technique. Multi-Moding Techniques. Other Broadbanding Techniques. Multifrequency Operation. Loaded Microstrip Antennas and Applications: Polarization Diversity Using Microstrip Antennas. Frequency Agile Microstrip Antennas. Radiation Pattern Control of Microstrip Antennas. Loading Effect of a Short. Compact Patch Antennas. Planar Inverted F Antenna. Dual-Frequency Microstrip Antennas. Dual-Frequency Compact Microstrip Antennas. Active Integrated Microstrip Antennas: Classification of Active Integrated Microstrip Antennas. Theory and Design of Active Integrated Microstrip Antenna Oscillators. Theory and Design of Active Integrated Microstrip Antenna Amplifiers. Frequency Conversion Active Integrated Microstrip Antenna Theory and Design. Design and Analysis of Microstrip Antenna Arrays: Parallel and Series Feed Systems. Mutual Coupling. Design of Linear Arrays. Design of Planar Arrays. Monolithic Integrated Phased Arrays.

Abstract: The conditions for antenna diversity action are investigated. In terms of the fields, a condition is shown to be that the incident field and the far field of the diversity antenna should obey (or nearly obey) an orthogonality relationship. The role of mutual coupling is central, and it is different from that in a conventional array antenna. In terms of antenna parameters, a sufficient condition for diversity action for a certain class of high gain antennas at the mobile, which approximates most practical mobile antennas, is shown to be zero (or low) mutual resistance between elements. This is not the case at the base station, where the condition is necessary only. The mutual resistance condition offers a powerful design tool, and examples of new mobile diversity antennas are discussed along with some existing designs.

Abstract: Multiple-antenna systems, also known as multiple-input multiple-output radio, can improve the capacity and reliability of radio communication. However, the multiple RF chains associated with multiple antennas are costly in terms of size, power, and hardware. Antenna selection is a low-cost low-complexity alternative to capture many of the advantages of MIMO systems. This article reviews classic results on selection diversity, followed by a discussion of antenna selection algorithms at the transmit and receive sides. Extensions of classical results to antenna subset selection are presented. Finally, several open problems in this area are pointed out.

Abstract: Preface. 1. Properties of Antennas. 2. Radiation Structures and Numerical Methods. 3. Arrays. 4. Aperture Distributions and Arrays Synthesis. 5. Dipoles, Slots, and Loops. 6. Microstrip Antennas. 7. Horn Antennas. 8. Reflector Antennas. 9. Lens Antennas. 10. Traveling Wave Antennas. 11. Frequency-Independent Antennas. 12. Phased Arrays. Index.

Abstract: Multiple-input-multiple-output (MIMO) wireless systems use multiple antenna elements at transmit and receive to offer improved capacity over single antenna topologies in multipath channels In such systems, the antenna properties as well as the multipath channel characteristics play a key role in determining communication performance This paper reviews recent research findings concerning antennas and propagation in MIMO systems Issues considered include channel capacity computation, channel measurement and modeling approaches, and the impact of antenna element properties and array configuration on system performance Throughout the discussion, outstanding research questions in these areas are highlighted