Multi-band planar inverted-F antenna

摘要

A multi-band planar inverted-F antenna includes a radiating unit (2), a ground unit (1) and a feeding unit (3). The radiating unit (2) includes a common radiating element (21), a high-frequency (HF) radiating element (22) and a low-frequency (LF) radiating element (23). A quasi U-shaped slot (233) is defined between the HF radiating element (22) and the LF radiating element (23). The ground unit (1) is electrically connected to one side of the common radiating element (21). The feeding unit (3) includes a strip (31) electrically connected to one side of the HF radiating element (22). The ground unit (1) includes a ground point (11) and an inverted-L short-line (12) connected to the ground point (11) at one end thereof. The inverted-L short-line (12) is also electrically connected to the common radiating element (21) at another end thereof. A loop surface current induced by the inverted-L short-line (12) can advantageously enhance bandwidth of the multi-band planar inverted-F antenna at frequencies of interest.