Mm-wave CMOS Matrix Distributed Amplifier for Ultra-Wideband Applications

This paper presents an mm-wave CMOS matrix distributed amplifier (matrix-DA) exhibiting an ultra-wide bandwidth. The amplifier consists of multi-tiered DAs and an on-chip inductive bias network. The distributed line length is optimized for dealing with a tradeoff between the impedance matching and bandwidth. The output signals from each gain cell are coherently added by adopting the group-delay equalization technique. Peaking lines are inserted at the interstage network to increase the gain-bandwidth product (GBP). The experimental results show that a nominal gain of 6.2 dB and a 3-dB bandwidth of 70 GHz is achieved. The GBP reaches 142.9 GHz. The return loss is higher than 10 dB over the entire 3-dB bandwidth. The chip size is 0.81 mm(2).