Analysis and Optimization of RF Front-End for MICS Band Receiver

An optimized receiver RF front-end, including inductorless Balun LNA and voltage driven double balanced passive mixer for medical implant communication service (MICS) is presented. The system operates in the 402-405 MHz MICS band. Balanced output, noise and distortion canceling were used in LNA design to achieve 29.26 dB of gain and 2.9 dB of NF. A 25% duty cycle, fully-differential voltage driven double balanced passive mixer is used. With this duty cycle the mixer is less sensitive to LO rise and fall time which will enhance noise figure and linearity. Simulated in 0.18 μm CMOS process, the front-end achieves a gain of 22dB, a NF of 3.05dB, a good linearity demonstrated by the P_-ldBof - 14.3dBm, IIP3 of 3.74dBm and IIP2 >50dBm. The front-end consumes 7.2mW from 1.8V power supply.