A quad-band front-end module for Wi-Fi and WiMAX applications using FBAR and LTCC technologies

In this paper, a compact Wi-Fi/WiMAX RF quad-band front-end module (FEM) is designed and implemented in order to meet this multi-mode trend. A quad-band FEM consists of 2- and 5-GHz Wi-Fi bandpass filters (BPFs), a 3-GHz WiMAX BPF, and two diplexers based on LTCC technology. In addition, a 5-GHz film bulk acoustic wave resonator (FBAR) filter, a single pole double throw (SPDT), and a single pole 4 throw (SP4T) are placed on top of the LTCC substrate. By taking advantage of three-dimensional design flexibility, the overall size of the module is less than 6.0 mm x 4.0 mm with an LTCC substrate thickness of 0.53 mm. The possible block diagram of the Wi-Fi/WiMAX FEM.