A Novel CMOS 24-GHz In-Phase Power Divider Using Synthetic Coupled Lines

A novel in-phase power divider using two synthetic coupled lines (CLs) and one isolation resistor is presented. The synthetic transmission lines (TLs) so-called the complementary-conducting-strip CL consists of periodical structures. By adopting the meandered and edge-coupled TLs the design reveals a two-way power divider and features a wideband behavior with a compact chip size. Moreover, the power divider also provides a 0° phase difference between input and output ports at 24 GHz. The chip is fabricated in a standard 0.18-μm CMOS technology with a core area of 30 μm × 30 μm. Measurements show that the minimum insertion losses (|S21| and |S31|) of the power divider are 5.38 and 5.43 dB at 23.5 GHz, respectively. Moreover, the power divider can operate from 15 to 28 GHz with superior RF performances on return losses and isolation.