A wide-band RF Front-end module for 5G mMIMO applications

This paper presents a 2-5 GHz mMIMO RF front-end module that includes an RF switch followed by two stages of low-noise amplifiers (LNA). The switch and LNAs are designed in 0.25um GaAs technology as two ICs, placed in a multi-chip module (MCM) and housed in a LGA package. The FEM achieves 47 dBm peak power handling in failsafe (FS)/TX mode, 1.35 dB noise figure, 31.5 dBm OIP3 and 17 dBm P1dB at 3.5 GHz. It also achieves a switching speed of 230 ns when tested with a very low frequency (1 KHz) toggle signal, a typical requirement on these FEMs. The excellent switching speed is accomplished through the use of a new time-adaptive bias technique to overcome interface trap charging inherent to the GaAs substrate. The RX module achieves the lowest reported noise figure & switching time while achieving high peak power handling in the FS mode operation.