Design for a Dual‐Frequency Antenna‐in‐Package

For an antenna‐in‐package (AiP), via holes are used to connect the antenna ground and system ground. In this letter, a dual‐frequency AiP with a U‐slot embedded in the patch is proposed. By properly arranging three via holes under the non‐radiating edge, an AiP with two resonant frequencies is realized. Then a U‐slot is embedded in the patch to further improve the bandwidth of the AiP. To validate the proposed design, an AiP with the bandwidth of 4.49% at 2.45 GHz and 6.02% at 5.32 GHz is achieved and fabricated. The measured results agree with the simulated results.