Reconfigurable antenna

Last updated
Reconfigurable antenna using a pixel architecture capable of reconfiguring dynamically its frequency of operation, radiation pattern and polarization. Reconfigurable pixel antenna.jpg
Reconfigurable antenna using a pixel architecture capable of reconfiguring dynamically its frequency of operation, radiation pattern and polarization.

A reconfigurable antenna is an antenna capable of modifying its frequency and radiation properties dynamically, in a controlled and reversible manner. [2] In order to provide a dynamic response, reconfigurable antennas integrate an inner mechanism (such as RF switches, varactors, mechanical actuators or tunable materials) that enable the intentional redistribution of the RF currents over the antenna surface and produce reversible modifications of its properties. Reconfigurable antennas differ from smart antennas because the reconfiguration mechanism lies inside the antenna, rather than in an external beamforming network. The reconfiguration capability of reconfigurable antennas is used to maximize the antenna performance in a changing scenario or to satisfy changing operating requirements.

Contents

Types of antenna reconfiguration

Reconfigurable antennas can be classified according to the antenna parameter that is dynamically adjusted, typically the frequency of operation, radiation pattern or polarization. [3]

Frequency reconfiguration

Frequency reconfigurable antennas can adjust their frequency of operation dynamically. They are particularly useful in situations where several communications systems converge because the multiple antennas required can be replaced by a single reconfigurable antenna. Frequency reconfiguration is generally achieved by physical or electrical modifications to the antenna dimensions using RF-switches, [4] impedance loading [5] or tunable materials. [6]

Radiation pattern reconfiguration

Radiation pattern reconfigurability is based on the intentional modification of the spherical distribution of the radiation pattern. Beam steering is the most extended application and consists of steering the direction of maximum radiation to maximize the antenna gain in a link with mobile devices. Pattern reconfigurable antennas are usually designed using movable/rotatable structures [7] [8] or switchable and reactively-loaded parasitic elements. [9] [10] [11] In the last 10 years, metamaterial-based reconfigurable antennas have gained attention due their small form factor, wide beam steering range and wireless applications. [12] [13] Plasma antennas have also been investigated as alternatives with tunable directivities. [14] [15] [16]

Polarization reconfiguration

Polarization reconfigurable antennas are capable of switching between different polarization modes. The capability of switching between horizontal, vertical and circular polarizations can be used to reduce polarization mismatch losses in portable devices. Polarization reconfigurability can be provided by changing the balance between the different modes of a multimode structure. [17]

Compound reconfiguration

Compound reconfiguration is the capability of simultaneously tuning several antenna parameters, for instance frequency and radiation pattern. The most common application of compound reconfiguration is the combination of frequency agility and beam-scanning to provide improved spectral efficiencies. Compound reconfigurability is achieved by combining in the same structure different single-parameter reconfiguration techniques [18] [19] or by reshaping dynamically a pixel surface. [1] [20]

Reconfiguration techniques

There are different types of reconfiguration techniques for antennas. Mainly they are electrical [4] (for example using RF-MEMS, PIN diodes, or varactors), optical, physical (mainly mechanical), [7] [8] and using materials. For the reconfiguration techniques using materials, the materials could be solid, liquid crystal, liquids (dielectric liquid [21] or liquid metal).

See also

Related Research Articles

Microelectromechanical systems Very small devices that incorporate moving components

Microelectromechanical systems (MEMS), also written as micro-electro-mechanical systems and the related micromechatronics and microsystems constitute the technology of microscopic devices, particularly those with moving parts. They merge at the nanoscale into nanoelectromechanical systems (NEMS) and nanotechnology. MEMS are also referred to as micromachines in Japan and microsystem technology (MST) in Europe.

A cryptosystem is considered to have information-theoretic security if the system is secure against adversaries with unlimited computing resources and time. In contrast, a system which depends on the computational cost of cryptanalysis to be secure is called computationally, or conditionally, secure.

Metamaterial Materials engineered to have properties that have not yet been found in nature

A metamaterial is any material engineered to have a property that is not found in naturally occurring materials. They are made from assemblies of multiple elements fashioned from composite materials such as metals and plastics. The materials are usually arranged in repeating patterns, at scales that are smaller than the wavelengths of the phenomena they influence. Metamaterials derive their properties not from the properties of the base materials, but from their newly designed structures. Their precise shape, geometry, size, orientation and arrangement gives them their smart properties capable of manipulating electromagnetic waves: by blocking, absorbing, enhancing, or bending waves, to achieve benefits that go beyond what is possible with conventional materials.

Finite-difference time-domain method

Finite-difference time-domain (FDTD) or Yee's method is a numerical analysis technique used for modeling computational electrodynamics. Since it is a time-domain method, FDTD solutions can cover a wide frequency range with a single simulation run, and treat nonlinear material properties in a natural way.

Physical optics Branch of optics

In physics, physical optics, or wave optics, is the branch of optics that studies interference, diffraction, polarization, and other phenomena for which the ray approximation of geometric optics is not valid. This usage tends not to include effects such as quantum noise in optical communication, which is studied in the sub-branch of coherence theory.

Characteristic modes (CM) form a set of functions which, under specific boundary conditions, diagonalizes operator relating field and induced sources. Under certain conditions, the set of the CM is unique and complete and thereby capable of describing the behavior of a studied object in full.

Radio-frequency microelectromechanical system

A radio-frequency microelectromechanical system is a microelectromechanical system with electronic components comprising moving sub-millimeter-sized parts that provide radio-frequency (RF) functionality. RF functionality can be implemented using a variety of RF technologies. Besides RF MEMS technology, III-V compound semiconductor, ferrite, ferroelectric, silicon-based semiconductor, and vacuum tube technology are available to the RF designer. Each of the RF technologies offers a distinct trade-off between cost, frequency, gain, large-scale integration, lifetime, linearity, noise figure, packaging, power handling, power consumption, reliability, ruggedness, size, supply voltage, switching time and weight.

Vivaldi antenna Type of broadband antenna

A Vivaldi antenna or Vivaldi aerial or tapered slot antenna is a co-planar broadband-antenna, which can be made from a solid piece of sheet metal, a printed circuit board, or from a dielectric plate metalized on one or both sides.

A dielectric resonator antenna (DRA) is a radio antenna mostly used at microwave frequencies and higher, that consists of a block of ceramic material of various shapes, the dielectric resonator, mounted on a metal surface, a ground plane. Radio waves are introduced into the inside of the resonator material from the transmitter circuit and bounce back and forth between the resonator walls, forming standing waves. The walls of the resonator are partially transparent to radio waves, allowing the radio power to radiate into space.

Linda Katehi Greek-American engineer and university administrator

Linda Pisti Basile Katehi-Tseregounis is a Greek-American engineering professor and former university administrator.

Metamaterial antenna

Metamaterial antennas are a class of antennas which use metamaterials to increase performance of miniaturized antenna systems. Their purpose, as with any electromagnetic antenna, is to launch energy into free space. However, this class of antenna incorporates metamaterials, which are materials engineered with novel, often microscopic, structures to produce unusual physical properties. Antenna designs incorporating metamaterials can step-up the antenna's radiated power.

Tunable metamaterial

A tunable metamaterial is a metamaterial with a variable response to an incident electromagnetic wave. This includes remotely controlling how an incident electromagnetic wave interacts with a metamaterial. This translates into the capability to determine whether the EM wave is transmitted, reflected, or absorbed. In general, the lattice structure of the tunable metamaterial is adjustable in real time, making it possible to reconfigure a metamaterial device during operation. It encompasses developments beyond the bandwidth limitations in left-handed materials by constructing various types of metamaterials. The ongoing research in this domain includes electromagnetic materials that are very meta which mean good and has a band gap metamaterials (EBG), also known as photonic band gap (PBG), and negative refractive index material (NIM).

C-Band All Sky Survey

The C-Band All Sky Survey (C-BASS) is a radio astronomy project that aims to map the entire sky in the C Band (5 GHz). It has been conducted on two radio telescopes, one operating in the Karoo in South Africa, the other at Owens Valley Radio Observatory in California.

An electromagnetic metasurface refers to a kind of artificial sheet material with sub-wavelength thickness. Metasurfaces can be either structured or unstructured with subwavelength-scaled patterns in the horizontal dimensions.

Debatosh Guha is an Indian Antenna Researcher and a Professor in the Institute of Radio Physics and Electronics at the Rajabazar Science College, University of Calcutta. He also served Indian Institute of Technology Kharagpur as a HAL Chair Professor for a period during 2015-2016.

Weng Cho Chew Malaysian-American electrical engineer

Weng Cho Chew is a Malaysian-American electrical engineer and applied physicist known for contributions to wave physics, especially computational electromagnetics. He is a Distinguished Professor of Electrical and Computer Engineering at Purdue University.

Transmitarray antenna

A transmitarray antenna is a phase-shifting surface (PSS), a structure capable of focusing electromagnetic radiation from a source antenna to produce a high-gain beam. Transmitarrays consist of an array of unit cells placed above a source (feeding) antenna. Phase shifts are applied to the unit cells, between elements on the receive and transmit surfaces, to focus the incident wavefronts from the feeding antenna. These thin surfaces can be used instead of a dielectric lens. Unlike phased arrays, transmitarrays do not require a feed network, so losses can be greatly reduced. Similarly, they have an advantage over reflectarrays in that feed blockage is avoided.

Yuen Tze Lo was a Chinese American electrical engineer and academician. He was a professor emeritus at the Department of Electrical and Computer Engineering at University of Illinois at Urbana–Champaign. He is best known for his contributions to the theory and design of antennas. He is the editor of the textbook series, Antenna Handbook.

David Michael Pozar is an American electrical engineer, educator and professor emeritus at the Department of Electrical and Computer Engineering at University of Massachusetts Amherst. His research interests concentrate mainly on antenna theory and design. Pozar is also the author of the textbook, Microwave Engineering.

Method of moments (electromagnetics) Numerical method in computational electromagnetics

The method of moments (MoM), also known as the moment method and method of weighted residuals, is a numerical method in computational electromagnetics. It is used in computer programs that simulate the interaction of electromagnetic fields such as radio waves with matter, for example antenna simulation programs like NEC that calculate the radiation pattern of an antenna. Generally being a frequency-domain method, it involves the projection of an integral equation into a system of linear equations by the application of appropriate boundary conditions. This is done by using discrete meshes as in finite difference and finite element methods, often for the surface. The solutions are represented with the linear combination of pre-defined basis functions; generally, the coefficients of these basis functions are the sought unknowns. Green's functions and Galerkin method play a central role in the method of moments.

References

  1. 1 2 Rodrigo, D.; Cetiner, B.A.; Jofre, L. (2014). "Frequency, Radiation Pattern and Polarization Reconfigurable Antenna Using a Parasitic Pixel Layer". IEEE Trans. Antennas Propag. 62 (6): 3422. Bibcode:2014ITAP...62.3422R. doi:10.1109/TAP.2014.2314464. S2CID   22316165.
  2. J.T. Bernhard. (2007). "Reconfigurable Antennas". Synthesis Lectures on Antennas. 2: 1–66. doi:10.2200/S00067ED1V01Y200707ANT004.
  3. G.H. Huff and J.T. Bernhard. (2008). "Reconfigurable Antennas". In C.A. Balanis (ed.). Modern Antenna Handbook. John Wiley & Sons.
  4. 1 2 Panagamuwa, C.J.; Chauraya, A.; Vardaxoglou, J.C. (2006). "Frequency and beam reconfigurable antenna using photoconducting switches". IEEE Trans. Antennas Propag. 54 (2): 449. Bibcode:2006ITAP...54..449P. doi:10.1109/TAP.2005.863393. S2CID   8074147.
  5. Erdil, E; Topalli, K; Unlu, M; Civi, O; Akin, T (2007). "Frequency tunable microstrip patch antenna using RF MEMS technology". IEEE Trans. Antennas Propag. 55 (4): 1193. Bibcode:2007ITAP...55.1193E. doi:10.1109/TAP.2007.893426. S2CID   19335959.
  6. Liu, L.; Langley, R. (2008). "Liquid crystal tunable microstrip patch antenna". Electronics Letters. 44 (20): 1179. Bibcode:2008ElL....44.1179L. doi:10.1049/el:20081995.
  7. 1 2 Chiao, J.C.; Fu, Y.; Chio, I.M.; DeLisio, M.; Li, L.Y. (1999). MEMS reconfigurable vee antenna. IEEE MTT-S International Microwave Symposium. Vol. 4. pp. 1515–1518. doi:10.1109/MWSYM.1999.780242. ISBN   978-0-7803-5135-6. S2CID   7946482.
  8. 1 2 Rodrigo, D.; Jofre, L.; Cetiner, B.A. (2012). "Circular Beam-Steering Reconfigurable Antenna With Liquid Metal Parasitics". IEEE Trans. Antennas Propag. 60 (4): 1796. Bibcode:2012ITAP...60.1796R. doi:10.1109/TAP.2012.2186235. S2CID   36089245.
  9. Aboufoul, T.; Parini, C.; Chen, X.; Alomainy, A. (2013). "Pattern-Reconfigurable Planar Circular Ultra-Wideband Monopole Antenna". IEEE Trans. Antennas Propag. 61 (10): 4973. Bibcode:2013ITAP...61.4973A. doi:10.1109/TAP.2013.2274262. S2CID   9565138.
  10. Harrington, R.F. (1978). "Reactively controlled directive arrays". IEEE Trans. Antennas Propag. 26 (3): 390–395. Bibcode:1978ITAP...26..390H. doi:10.1109/TAP.1978.1141852.
  11. Hum, S.V.; Perruisseau-Carrier, J. (2014). "Reconfigurable Reflectarrays and Array Lenses for Dynamic Antenna Beam Control: A Review". IEEE Trans. Antennas Propag. 62 (1): 183. arXiv: 1308.4593 . Bibcode:2014ITAP...62..183H. doi:10.1109/TAP.2013.2287296. S2CID   32075766.
  12. Mookiah, P.; Dandekar, K.R. (2009). "Metamaterial-substrate antenna array for MIMO communication system". IEEE Transactions on Antennas and Propagation. 57 (10): 3283. Bibcode:2009ITAP...57.3283M. doi:10.1109/TAP.2009.2028638. S2CID   22859024.
  13. Gulati, N.; Dandekar, K.R. (2014). "Learning State Selection for Reconfigurable Antennas: A multi-armed bandit approach". IEEE Transactions on Antennas and Propagation. 62 (3): 1027. Bibcode:2014ITAP...62.1027G. doi:10.1109/TAP.2013.2276414. S2CID   1061713.
  14. Borg, Gerard G.; Harris, Jeffrey H. (24 May 1999). "Application of plasma columns to radiofrequency antennas". Applied Physics Letters . 74 (22): 3272–3274. Bibcode:1999ApPhL..74.3272B. doi:10.1063/1.123317.
  15. Kumar, Rajneesh; Bora, Dhiraj (3 March 2010). "A reconfigurable plasma antenna". Journal of Applied Physics . 107 (5): 053303–053303–9. Bibcode:2010JAP...107e3303K. doi:10.1063/1.3318495.
  16. Alexeff, I.; et al. (18 April 2006). "Experimental and theoretical results with plasma antennas". IEEE Transactions on Plasma Science. 34 (2): 166–172. Bibcode:2006ITPS...34..166A. doi:10.1109/TPS.2006.872180. S2CID   32033839.
  17. Simons, R.N.; Donghoon, C.; Katehi, L.P.B. (2002). Polarization reconfigurable patch antenna using microelectromechanical systems (MEMS) actuators. IEEE Antennas Propag. Soc. Int. Symp. Vol. 2. pp. 6–9. doi:10.1109/APS.2002.1016015. hdl:2060/20020063517. ISBN   978-0-7803-7330-3. S2CID   108547161.
  18. X.S., Yang; Wang, B.Z.; Wu, W.; Xiao, S. (2007). "Yagi Patch Antenna With Dual-Band and Pattern Reconfigurable Characteristics". IEEE Antennas Wirel. Propag. Lett. 6 (11): 168. Bibcode:2007IAWPL...6..168Y. doi:10.1109/LAWP.2007.895292. S2CID   7752473.
  19. Aboufoul, T.; Chen, X.; Parini, C.; Alomainy, A. (2014). "Multiple-parameter reconfiguration in a single planar ultra-wideband antenna for advanced wireless communication systems". IET Microwaves, Antennas & Propagation. 8 (11): 849–857. doi:10.1049/iet-map.2013.0690.
  20. Pringle, L.N.; et al. (2004). "A reconfigurable aperture antenna based on switched links between electrically small metallic patches". IEEE Trans. Antennas Propag. 52 (6): 1434–1445. Bibcode:2004ITAP...52.1434P. doi:10.1109/TAP.2004.825648. S2CID   25035434.
  21. Motovilova, Elizaveta; Huang, Shao Ying (2020). "A Review on Reconfigurable Liquid Dielectric Antennas". Materials. 13 (8): 1863. Bibcode:2020Mate...13.1863M. doi: 10.3390/ma13081863 . PMC   7216238 . PMID   32316173.