An 18–40 GHz Wideband Millimeter-wave Front-end in 0.13-\mu \text{mSiGe}$ BiCMOS with > 30\%$ Peak PAE

In this paper, we present a broadband millimeter-wave (mm-wave) front end (FE) based on an asymmetric switch and bi-directional impedance matching network. To realize high efficiency over a wide bandwidth, the switch between the power amplifier (P A) and the antenna is substituted by the bi-directional matching network, which can transform the load impedance to the desired impedance of the amplifier in transmit mode as well as to transform the turn-off impedance at the root of the amplifier transistor to a high resistance region in receive mode. The broadband FE is implemented using 0.13 $\mu\mathrm{m}\text{SiGe}$ BiCMOS technology, with a size of 945 $\mu \mathrm{m}\times 916\mu \mathrm{m}$. In the TX-mode, the small signal 3-dB gain bandwidth of the FE covers from 20 to 40.5 GHz, with a maximum gain of 19.1 dB. The FE achieves a saturated output power of 19.1 - 20.3 dBm for large signals in the 18 - 40 GHz bandwidth, with peak efficiencies exceeding 30%. In the RX-mode, the FE achieves a 95.8% 3-dB small-signal gain fractional bandwidth, which covers 15.5 to 44 GHz. It achieves a noise figure (NF) of 6.35 - 7.56 dB over the frequency range of 18 - 40 GHz.