A concurrent dual-band mixer for 900-MHz/1.8GHz RF front-ends

A concurrent dual-band mixer is introduced that is capable of simultaneous operation in the 900MHz and 1800MHz frequency bands. A general description of the mixer implementation is provided with analysis of the dual-band matching network that achieves simultaneous narrow band matching in the two frequency bands of interest. The mixer is implemented in a 0.8 /spl mu/m SiGe BICMOS technology with f/sub T/ of 35 GHz. The mixer consumes 7.4 mA of current and achieves power conversion gain of 10.5 dB and 10.1 dB, input return losses of 15 dB and 10 dB, noise figure of 12.6 dB and 13 dB, and IIP3 of 2.6 dBm and 0.8 dBm in the two bands, respectively.