A Concurrent $Ku/K/Ka$ Tri-Band Distributed Power Amplifier With Negative-Resistance Active Notch Using SiGe BiCMOS Process

A new tri-band power amplifier (PA) on a 0.18- μm SiGe BiCMOS process, operating concurrently in Ku-, K-, and Ka-band, is presented. The concurrent tri-band PA design is based on the distributed amplifier structure with capacitive coupling to enable large device size, while maintaining wide bandwidth, gain cells with the enhanced-gain peaking inductor, and negative-resistance active notch filters for improved tri-band gain response. The concurrent tri-band PA exhibits measured small-signal gain around 15.4, 14.7, and 12.3 dB in the low band (10-19 GHz), midband (23-29 GHz), and high band (33-40 GHz), respectively. In the single-band mode, the PA has maximum output powers of 15, 13.3, and 13.8 dBm at 15, 25, and 35 GHz, respectively. When the PA is operated in dual-band mode, it has maximum output powers of 11.4/8.2 dBm at 15/25 GHz, 13.3/3 dBm at 15/35 GHz, and 8.7/6.7 dBm at 25/35 GHz. In the tri-band mode, it exhibits 8.8/5.4/3.8-dBm maximum output power at 15/25/35 GHz. The concurrent tri-band PA exhibits relatively flat responses in gain and output power across its three frequency bands and good matching up to 40 GHz.