Design of a millimetre-wave mixer for broadband mobile communications

The design process for a state-of-the-art millimetre-wave down converter from 65.5 GHz to 1.5 GHz is described in detail. The work starts with a short discussion of basic mixer theory and its implications on the performance for any mixer and then moves on to the problem of choosing the correct topology for a given task. Some of the specific problems encountered at millimetre-wave frequencies are discussed and the final chip layout is discussed. The design exhibits a simulated conversion loss of -0.7 dB at 0 dBm LO power and a measured minimum conversion loss of 2 dB at 8 dBm LO power. These results are compliant with current published state of the art.