Noise Analysis of CMOS Common-Source/Drain Active Balun

Common-source/drain active balun circuit is composed of just single transistor M1 as shown in Fig. 1, designed in complementary metal-oxide semiconductor (CMOS) technology. This active balun circuit is considered as the simplest topology amongst other active balun configurations. The input signal is fed into the gate of the transistor, and normal operation results in an inverted output signal at RFout2 and a non-inverted signal at RFout1. Ideally, the two outputs would have the same amplitude with a phase shift or difference of 180º. Load resistors R1 and R2 determine the output voltages as well as the voltage gains of the two output signals with respect to the input signa