[[File:Z Antennas at UHF Frequencies.jpg|thumb|Denne Z-antenne testet ved [[National Institute of Standards and Technology]] er mindre end en standardantenne med sammenlignelige egenskaber. Dens høje [[effektivitet]] fås fra "Z-elementet" i firkanten som virker som et [[metamateriale]], hvilket hjælper med at udstråle radiobølger. Firkantens sider er hver 30 millimeter og frekvensen er 570,4MHz (bølgelængde i vakuum: ca. 526 mm).<ref>[https://www.researchgate.net/publication/224088745_Experimental_Verification_of_Z_Antennas_at_UHF_Frequencies researchgate.net: Ziolkowski, R.W. & Jin, Peng & Nielsen, J.A. & Tanielian, M.H. & Holloway, Christopher. (2009). Experimental Verification of Z Antennas at UHF Frequencies. Antennas and Wireless Propagation Letters, IEEE. 8. 1329 - 1333. 10.1109/LAWP.2009.2038180]</ref>]]
'''Metamaterialeantenner''' er en klasse af [[radioantenne]]r, som anvender [[metamateriale]]r til at forbedre eller øge ydelsen af et [[radioantenne|antennesystem]].<ref name=Directive-emission>{{cite journal| last = Enoch| first = Stefan| format = Free PDF download. Cited by 248.| title = A Metamaterial for Directive Emission| journal = [[Phys. Rev. Lett.]]| volume = 89| issue = 21| pages = 213902| date = 2002-11-04| url = https://tayeb.fr/fac/PRL-Metamaterial-2002.pdf| doi = 10.1103/PhysRevLett.89.213902| accessdate = 2009-09-16| pmid = 12443413| last2 = Tayeb| first2 = G| last3 = Sabouroux| first3 = P| last4 = Guérin| first4 = N| last5 = Vincent| first5 = P| archive-date = 10. maj 2019| archive-url = https://web.archive.org/web/20190510224804/https://tayeb.fr/fac/PRL-Metamaterial-2002.pdf| url-status = unfit}}, </ref><ref name=neg-group-vel-1>{{cite journal| last =Omar F.| first =Siddiqui|author2 = Mo Mojahedi, George V. Eleftheriades|title =Periodically LTL With Effective NRI and Negative Group Velocity|journal =IEEE Transactions on Antennas and Propagation| volume =51 part 1 |issue =10| pages = 2619–2625| publisher =IEEE| location =Univ. of Toronto, Ont., Canada |date = 2003-10-14|doi =10.1109/TAP.2003.817556}}</ref> 
Anvendelsen af metamaterialer til at øge ydelsen af antenner har vundet stor interesse. Demonstrationer har vist at metamaterialer kan forbedre den udstrålede effekt af en antenne.<ref name=radiation-properties>{{cite journal| last =Kamil| first =Boratay Alici| author2 =Ekmel Özbay| title =Radiation properties of a split ring resonator and monopole composite| journal =Phys. Stat. Sol. (b)| volume =244| issue =4| pages =1192–1196| date =2007-03-22| url =http://www.fen.bilkent.edu.tr/~ozbay/Papers/154-07-bora-pssb.pdf| doi =10.1002/pssb.200674505| accessdate =2009-09-17| archive-date = 3. marts 2016| archive-url =https://web.archive.org/web/20160303173946/http://www.fen.bilkent.edu.tr/~ozbay/Papers/154-07-bora-pssb.pdf| url-status =unfit}},  Citat: "...The application of metamaterials to increase antenna performance is of great interest. It was shown that introducing metamaterials could enhance the radiated power of the antenna [8]. Moreover, negative magnetic permeability materials are a candidate for obtaining properties such as an electrically small antenna size [9–14], high directivity [15, 16], and tunable operational frequency [13, 17]..."</ref>
<ref name=Antenna-substrate>{{cite journal| last =Wu| first =B.-I.| author2 =W. Wang, J. Pacheco, X. Chen, T. Grzegorczyk and J. A. Kong| title =A Study of Using Metamaterials as Antenna Substrate to Ehance Gain| journal =Progress in Electromagnetics Research| volume =51| pages =295–328 (34 pages)| publisher =EMW Publishing| location =[[MIT]],Cambridge,MA,USA| year =2005| url =http://ceta.mit.edu/pier/pier51/17.0407071.Wu.WPCGK.pdf| doi =10.2528/PIER04070701| accessdate =2009-09-21| archive-date = 3. juli 2010| archive-url =https://web.archive.org/web/20100703073253/http://ceta.mit.edu/pier/pier51/17.0407071.Wu.WPCGK.pdf| url-status =bot: unknown}}</ref> Materialer som kan give negativ [[magnetisk permeabilitet]] kan f.eks. tilbyde egenskaber såsom små antenner på brøkdele af en bølgelængde, høj retningsbestemthed – og afstembar arbejdsfrekvens, inklusiv et system af antenner. Ydermere har metamateriale baserede antenner demonstreret forbedret effektivitet-båndbredde ydelse.<ref name=radiation-properties/>
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