A Wideband Co-Linearly Polarized Full-Duplex Antenna-in-Package With High Isolation for Integrated Sensing and Communication

In this letter, a novel co-linearly polarized full-duplex antenna-in-package (AiP) with high Tx/Rx isolation and wide decoupled bandwidth is proposed for integrated sensing and communication (ISAC). Fan-out wafer-level packaging technology is employed, and the preparation process is discussed in details. To improve Tx/Rx isolation, the current direction of the patch elements is orthogonal to that of the feeding ports. Two identical 1 × 2 patch antenna arrays are used as Tx and Rx antennas, respectively. To further suppress mutual coupling, a decoupling loop is proposed to enhance Tx/Rx isolation. In addition, a wideband full-duplex AiP with high isolation and wide decoupled bandwidth is also proposed by using the parasitic technique and the proposed decoupling method. Prototypes are fabricated and measured to verify the proposed AiPs. The measurement results demonstrate that the proposed AiP possesses the merits of high Tx/Rx isolation (up to 53 dB), wide isolation bandwidth (up to 9.2%) and low cost, providing a foundation for chip-level applications in ISAC.