| The RF mixer circuit is a key component in a wireless transceiver system. The main objective of a mixer circuit is to provide frequency conversion, allowing signals to be processed effectively. The theory, design, simulation, layout and testing of a 1.2V Gilbert Cell mixer is presented in this thesis. The mixer was designed for application in the wireless sensor network being designed by the MSCAD team at the University of Arkansas, and it functioned as a down-converter, using an RF input signal of 440 MHz and a LO signal of 430 MHz. It was designed to achieve high gain and linearity using the current bleeding and source degeneration techniques. The circuit was fabricated in a 130 nm process and tested on a designed PCB test board. The mixer proved to have functional operation as an up and down-converter. The voltage gain was measured as -4 dB and the 1 dB compression point at -8 dBm. Techniques to further improve the operation of the mixer are given in the conclusion of this work. |
