Radiator-Shared Self-Decoupled Antennas Designed for Adjacent Frequency Bands

A novel self-decoupled antenna pair for adjacent frequency bands using a shared strip-like patch is proposed in this paper. Two distinct planar inverted-L antennas (PILAs) are placed in a back-to-back arrangement to excite the same strip patch, forming two integrated antennas, one working in the 2.45 GHz WiFi band (2400 - 2483.5 MHz) and the other in the N41 band (2496 – 2690 MHz). By controlling the relative distance between two PILAs and the relative height of the patch, the coupled energy from two coupling paths is regulated to mitigate with each other at the passive antenna, showing a naturally self-decoupling performance. In the proposed scheme, no additional decoupling structure is introduced and the high isolation is realized between the antennas just simply integrating three resonators, showing a simple structure. The designed antenna can achieve an improvement in isolation from 7 dB to above 20 dB in the adjacent band of 2.45 - 2.55 GHz.