A CPW‐fed slot antenna with embedded ring‐type strip for dual‐frequency operation

Abstract

The coplanar waveguide‐fed planar slot antenna with the embedded ring‐type strip for dual‐frequency operation is investigated and experimentally explores in this letter. The prototype, which is implemented on the 0.8‐mm FR‐4 substrate with εr = 4.4, indicates that the embedded ring‐type strip offers extended path for the electric current flow, achieving 45.1% size reduction of the fundamental resonant mode. The ratio of the center frequencies of the first two resonant bands can be tuned within a range wider than 1.81 by increasing the radius and line width of ring‐type strip. Furthermore, the fundamental resonant mode can be shifted to the higher frequency to combine with the second resonant mode of the circular slot, indicating the wideband operation with the bandwidth of 1332 MHz (40.5%). © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2882–2887, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26370

Miniaturised printed slot antenna with multi‐ring technique for dual‐band and broadband operations

“…The differences between [16] and this paper are that a second metallic ring is added in the slot, and an asymmetric shape feeding structure is used. The second metallic ring with radius and width R 11 and g 11 generates a new resonant mode in the high-band, and improves the bandwidth.…”