Coupled-fed shorted strip antenna with an inductively coupled branch strip for low-profile, small-size LTE/WWAN tablet computer antenna

A low-profile, small-size (10 × 40 mm2 on a thin dielectric substrate) planar LTE/WWAN antenna suitable for slim tablet computer application is presented. The antenna is formed by a coupled-fed shorted strip antenna and an inductively coupled branch strip, with a chip inductor of 22 nH connected therebetween. At higher frequencies, owing to the high inductive reactance provided by the chip inductor, the branch strip will have very small effects on the antenna performances, and the coupled-fed shorted strip antenna alone can provide a high-band operation of 1710–2690 MHz. At lower frequencies, the embedded chip inductor can decrease the antenna's required resonant length, and the coupling feed can greatly widen the bandwidth of the excited resonant mode such that the antenna can cover a low-band operation of 704–960 MHz. Good radiation characteristics of the antenna in the low-band and high-band operations are also obtained. Details of the proposed antenna and its experimental and simulated results are presented. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1041–1046, 2014