The Optimization And Verification In Design Of SSB (Single Side Band) Mixers

Wireless communication is the most rapid development of the national pillar industry in recent years,as the core module of the wireless transceiver system,the design of the mixer and the poly-phase filter has always become a focus of present study.The Process dimension of CMOS continuously decreases scaled,at the same time,the performance of transistor has been greatly improved,making the realization of Wireless Transceiver RF fore-end integrated become possible.With the development of wireless communication standards and the increase the frequency of the wireless communication,the more high-performance RF front-end transceiver is required.Mixers,which plays an important role in RF front-end transmitter,its performance determines the power and cost of the RF transmitter.This paper introduces the basic knowledge of RF circuit,including the simulation algorithm RF circuit of the RF circuit ? matching network ? nonlinear effects of RF MOS model and so on.Because of the professional particularity,this article focuses on the simulation algorithm to do a detailed introduction.Cadence is known for its full custom IC design ability,which includes tools such as Virtuoso Schematic Composer,Affirma Analog Design Environment,Virtuoso Layout Editor,Affirma Spectra,Virtuoso Layout Synthesizer,Assura Verification Environment,and Dracula and so on.The Mixer measurements described in paper are calculated using Spectre RF in the Analog Design Environment.we can calculate the voltage convergence gain by Using a two-tone large-signal QPSS analysis which is more time-consuming.The power convergence gain,in general,requires that you run the two-tone large-signal QPSS analysis.In this paper,a new-type mixer based on the traditional Gilbert mixer structure,which can operate at frequency 911 MHz & 900 MHz and 1.8V supply voltages is designed,and the mixer is made up of switching ? trans-conductance and load transistors.In the new-type mixer,the stacked structure is replaced by the folding structure between switching and trans-conductance,so that it can work in the condition of low voltage;The Current-reuse Bleeding Technique is used to improve the conversion gain in trans-conductance;The LC resonating network ? self-biasing circuit is used to improve linearity;And the three improvement measures mentioned above are also beneficial to noise.This design is based on 0.18?m CMOS technology of GSMC,the Spectre RF tools of Cadence to simulate the mixer.The simulation results show that the conversion gain of the mixer is 13.8d B,l d B compression point is about-4.3d Bm,the input power of third-order intercept point is 4.8d Bm.At intermediate frequency11 MHz,the SSB(single side-band)noise figure is 9.1d B,the power consumption is22 m W,it meets requirements of the mixer.