Broadband planar antenna with T‐shaped strip and capacitively coupled shorted strip

This letter describes a broadband planar antenna embedded in LTE700/GSM handheld terminals. The antenna consists of a T‐shaped strip fed by a 50‐Ω coaxial cable and a shorted strip excited by capacitive coupling. The capacitively coupled shorted strip shows the resonance at the lower frequency band, and the T‐shaped strip presents good matching at the higher frequency band, because the characteristics of input impedance are affected by the capacitive coupling. The proposed antenna was simulated and fabricated. The measured bandwidth based on 3:1 VSWR was 0.62–1.53 GHz, which covers the frequencies used for LTE700, GSM800/850/900 mobile communications as well as the military applications. This antenna would be also useful for broadband wireless communications using the technique such as software‐defined radio or cognitive radio.