A tri-band MIMO transceiver for mobile WiMAX with an image rejection ratio tunable SSB mixer

We fabricated a multiband transceiver for mobile WiMAX in 90-nm CMOS technology. It operates at three RF bands (2.3/2.5/3.5 GHz) with a large dynamic range. We adopted a double conversion receiver that can switch lower and upper local modes. An image rejection ratio (IRR) tunable single side-band (SSB) mixer was used to achieve over 50 dB IRR. The RCE for 2.5 GHz at -71.5 dBm input was -28.7 dB and maximum input level up to -20 dBm was achieved using variable gain LNAs and mixers. The transmitter had a dynamic range of over 56 dB.