Preamplifier effect on the performance of distributed active mixer

In this paper, a new distributed active mixer is presented. The scheme is based on the conventional Gilbert-cell multiplier with complementary transconductance stage. By adding the preamplifier and non-uniform artificial transmission lines on the topology, the new distributed active mixer is obtained. Comparison of the new mixer with the topology in absence of preamplifier shows that it has higher conversion gain and lower noise figure. The proposed mixer is simulated in a 0.18 μm CMOS technology, with a LO power of 5 dBm and IF frequency of 70 MHz. The simulated circuit has a conversion gain of 12 dB over -3dB bandwidth and an average input third-order intercept point (IIP3) of -3 dBm within the entire frequency range. It consumes a dc power of 64 mW from a 2 V supply voltage.