A Miniaturized GPS Antenna for Limited Space

In this paper, a miniaturized global positioning system (GPS) antenna is proposed inside a terminal device with limited space. The size of the terminal device is approximated to be 0.3 λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf> × 0.1 λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf> × 0.03 λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf> and contains many metal elements that affect the bandwidth of the antenna such as battery and metal coils. The circular polarization was formed by using the the inverted-F antenna(IFA) and the edge of the ground next to it, and miniaturization was achieved by introducing L-shaped folded branches at the ground. By utilizing the metal ground, the folded branch, and the IFA, miniaturization and circular polarization are achieved in the special scenario with high radiation efficiency. The designed antenna operates in the GPS L1 band and is suitable for small tracking and positioning devices.