Low-Profile and Electrically Small Meander-Line Antenna Using a Capacitive Feed Structure

• Published in: IEEE antennas and wireless propagation letters Vol. 11; pp. 1281 - 1284
• Main Authors: Saito, Y., Fukusako, T.
• Format: Journal Article
• Language: English
• Published: New York IEEE 2012; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna feeds; Antenna gain; Antenna measurements; Antennas; capacitive feed structure; Conductors (devices); Forming; Gain; Ground plane; Impedance; Meanders; radiation efficiency; Resonant frequency; small antenna; Wavelengths; Wavenumber
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2012.2226636

An electrically small and low-profile meander-line antenna using a capacitive feed structure is presented. The meander line has a length of one quarter-wavelength with a shorted end, and the capacitive feed structure is installed at the other end. A back conductor, which works as a ground plane, is located at a distance of 0.01λ 0 to the meander-line element forming in the area of 0.121λ 0 × 0.075λ 0 , which satisfies the condition of electrically small antennas (ka = 0.435 <; 0.5, wavenumber k, radius a of a sphere surrounding the antenna, and wavelength λ 0 at the resonance frequency). The fabricated antenna has successfully achieved a peak gain of 0.62 dBi and exhibits a higher radiation efficiency of more than 30% compared to an inverted-F antenna of the same dimension.