A Ka-Band CMOS Wilkinson Power Divider Using Synthetic Quasi-TEM Transmission Lines

This work presents a Ka-band two-way 3 dB Wilkinson power divider using synthetic quasi-transverse electromagnetic (TEM) transmission lines (TLs). The synthetic quasi-TEM TL, also called complementary-conducting-strip TL (CCS TL), is theoretically analyzed. The equivalent TL model, whose production is based on the extracted results, is applied to the power divider design. The prototype is fabricated by the standard 0.18 mum 1P6M CMOS technology, showing the circuit size of 210.0 mumtimes390.0 mum without contact pads. The measurement results, which match the 50 Omega system, reveal perfect agreements with those of the simulations. The comparison reveals the following characteristics. The divider exhibits an equal power-split with the insertion losses (S
₂₁
and S
₃₁
) of 3.65 dB. The return losses (S
₁₁
, S
₂₂
and S
₃₃
) of the prototype are higher than 10.0 dB from 30.0 to 40.0 GHz.