Small microstrip helical antenna

A new design of a miniaturized microstrip helical antenna is proposed and presented for mobile communication. The antenna-size reduction is achieved by folding the simple microstrip line around a substrate. The measured data shows that this microstrip antenna provides wide bandwidth and the multiband characteristics. The bandwidth at 1.8 GHz is approximately 140 MHz. The co-polarized far-field radiation pattern of this antenna is quasi-omnidirectional. Details of the antenna design and experimental results are described and discussed.