Evolution and design trade-offs of a high performance, low-voltage downconversion mixer for wireless direct conversion receivers (DCR) are studied in this paper. As a first step, a mixer with active loads and adjustable conversion gain is presented. Then a different mixer topology that provides high conversion gain without deteriorating the linearity and noise performance is discussed. Finally, this topology is found to be well suitable for very low-voltage applications and thus its design and voltage scalability is depicted. The presented mixers are designed using a 0.35-/spl mu/m BiCMOS process and characterized at 2 GHz frequency.
['Kalle Kivekäs', 'Aarno Pärssinen', 'Jarkko Jussila', 'Jussi Ryynanen', 'Kari Halonen']
Design of low-voltage active mixer for direct conversion receivers