Analysis of process and temperature variations on a 2.4 GHz RF CMOS down conversion subthreshold mixer

The effect of process and temperature variations are becoming more dominant with technology scaling, especially for RF circuits, wherein even the minute variability in FETs and passive devices have a significant impact on the overall circuit behavior. Due to stringent power and performance specification requirements in the latest Wireless/RF applications, reasonable compensation for the process, voltage and temperature variations, is even more critical. In this paper, the design of a 2.4GHz operated, ultra-low power CMOS down-converting active mixer fabricated in standard 180 nm RF CMOS technology has been presented. The mixer is based on double balanced Gilbert-cell resistor-loaded topology. The effects of process and temperature variations on the designed mixer have been investigated and various compensation techniques relevant to the current design have been analyzed.