Designing Of RF Transmitter Front-end For P Band And L Band

With the continuous development and maturity of active electronically scanned array?AESA?,phased array is gradually becoming the mainstream architecture of modern radar.At the same time,the continuous improvement of IC technology has provided a feasible solution for the integration of RF power circuit and other RF circuit.Typically,a phased array radar contains several AESAs,and each AESA is made up of hundreds of transmit/receive?T/R?components,and the performance of the T/R component will have a significant impact on the overall system performance.Therefore,the research on the RF front-end of broadband T/R components with high linearity is the key to improve the performance and reliability of phased array radar.In this paper,the status quo of RF front-end research is reviewed,and several architectures,including super heterodyne,zero IF and digital conversion architecture and their derivatives are analyzed and the indexes that affect the system performance are introduced.An improved quadrature IF upconversion scheme is proposed,and the method of link budget allocation is described in detail.A fully integrated RF front-end transmitter based on TSMC 0.18?m RFCMOS process is proposed for P band and L band?405M².2GHz?applications.The system which consists of single-to-double balun,mixer,variable-gain amplifier and driver amplifier,is based on improved quadrature IF upconversion architecture.A single-to-double balun with noise canceling,distortion canceling and wideband impedance matching is adopted in IF and LO port.Mixer is based on quadrature double balanced Gilbert architecture.A variable-gm cascode structure is used in variable-gain amplifier.A push-pull structure with high linearity and wideband matching character is adopted in driver amplifier.The post-layout simulation results indicate that under 3.3V supply voltage,the transmitter front-end obtains a current consumption of 94mA,layout area of3.0mm×2.4mm,voltage gain spanning from 10dB to 30dB,P_out-1dB>10dBm,NF<8dB when IF frequency above 25MHz,and reflection coefficient of IF ports below-20dB,LO ports and RF port below-15dB.