Small-Size Coupled-Fed Antenna With Two Printed Distributed Inductors for Seven-Band WWAN/LTE Mobile Handset

A compact small-size coupled-fed antenna with two symmetrical printed meandered inductive strips as two distributed inductors for seven-band operation covering the GSM850/900/1800//1900/UMTS2100/LTE2300/2500 bands in the internal mobile handset application is proposed. Wideband operation is achieved by incorporating a feeding strip and two radiating strips of different lengths, which are both disposed on the no-ground board space of the proposed antenna. The desired lower bands of GSM850/900 operation can be achieved by the two radiating strips of different lengths, which provide a quarter-wavelength dual-resonance mode at 810 and 962 MHz. While the feeding strip can provide a quarter-wavelength resonant mode at around 1.78 GHz, and other resonant modes at 2.45 GHz are contributed by the higher-order resonant modes of the two radiating strips, covering the desired upper bands of DCS1800/PCS1900/UMTS2100/LTE2300/2500 operation. In addition, the proposed antenna only occupies a planar size of 15×30 mm2 and is easily printed on one surface of a FR4 substrate, which makes it suitable for practical mobile applications. Detailed considerations of the design and main parameters are studied in this communication and the proposed antenna is successfully simulated, fabricated, and measured.