This paper presents a type of antenna structure

in which a Γ structure is fed by monopole through electromagnetic coupling.Simulation and experimental results show that

compared to the general monopole antenna

the height of this antenna can be cut in half

the relative bandwidth can be broadened to 66%.So this structure achieves miniaturization and broadband of antenna.Signal radiated by this antenna has a linear phase-frequency character and small distortion

so it can be used to send broadband signals.By special designing

we can improve matching and the gain.The VSWR(Voltage Standing Wave Ratio) is less than 2 in the whole working bandwidth

while the gain increases about 2 dBi at the low frequency of the working bandwidth and 1 dBi at the high frequency.