Small GPS antenna with lumped elements and interdigital structure

In this paper, a miniaturized global positioning system (GPS) antenna embedded in a printed circuit board (PCB) is presented. The proposed antenna employs lumped elements and an interdigital structure to reduce an operating frequency and to achieve good input matching. Furthermore, the system ground plane is included to work out a radiator. The size of the proposed antenna is 8 mm × 4.5 mm. The bandwidth under VSWR of 2∶1 is 20 MHz from 1561 MHz to 1581 MHz. The measured antenna gain and the efficiency are 1 dBi and 40% at 1575 GHz, respectively.