2.4GHz CMOS Design And Simulation Of Mixer

Recently, with the continual progress in CMOS process and an explosive growth in wireless communications, it has made the research on RFIC become the hotspot. Mixer is one of the most important modules in RF transceiver and is used to transform the frequency. It affects the whole performance of the transceiver.This thesis makes a brief introduction to the structures of the transceivers and analyzes the two important indexes that affect the performance of the transceivers. Meanwhile it provides the formulas of noise and linearity for cascode system and aquires some guides based on this. The design mainly focuses on the performance of devices and then it introduces the performance of inductors, capacitors and transistors and its fabrication in CMOS RFIC. Also the analysis of mixer is undertaken. First of all, the principle of mixers and its performance index including linearity, gain, noise figure as well as resistance matching is listed. Linearity is a crucial index that may influence dynamic scope of the receivers. Hence analysis on non-linearity distortion of typical Gilbert mixers is achieved. Accordingly a method optimizing the linearity is proposed and an improved structure of mixer is presented. Under the method, linearity improves when other indexes keep the same. In order to illustrate the optimizations it is well deduced. ADS has enabled the simulation of the structure and two important indexes such as third-order intercept point and 1dB compression point are satisfying. Finally layout design is done.Due to the limit on the classical Gilbert mixers it is not a good choice for low voltage application. Therefore, the last chapter proposes a novel improved even-harmonic mixer. Such folded-cascode mixer can act in low voltage application and current reuse can achieve amazing gain and linearity. The simulation is satisfying.