A novel single‐band RF front‐end module for wireless communication systems

Abstract

In this article, a novel integrated RF front-end module (FEM) for wireless communication system is realized by low temperature co-fired ceramic (LTCC) technology. The proposed RF FEM has four ports and consists of a novel selectable filter, balun, which are fully embedded in the LTCC substrate, and two PIN diodes. This novel selectable filter can be applied for either lowpass filter (LPF) for Tx path or bandpass filter (BPF) for Rx path by simply making output port to be shorted to the ground. The fabricated single-band RF FEM has nine pattern layers including two ground layers and it occupies less than 2.3 Â 4.0 Â 0.44 mm 3 . In case of Tx path, the measured insertion loss at 2-GHz band is less than 2.3 dB and a return loss of more than 16.8 dB. Furthermore, it provide a more than 40.5 dB second harmonic suppression at 2-GHz is obtained. In case of Rx path, the measured insertion loss at 2-GHz band is less than 1.2 dB and a return loss of more than 16.7 dB. The measured results of the implemented RF FEM are in good agreement with the simulated results.