22-27GHz Inductive Feedback Cascode Amplifier With Flat Group Delay Variation

The wideband low noise amplifier as a receiver front-end component of communication,radar,electronic warfare,wireless sensor system,plays a decisive role in the RF small signal processing.It not only has strict requirements on bandwidth,gain,noise figure and power consumption,but also and stringent performance requirements on energy linearity and phase linearity.In OFDM systems,power linearity must meet a stringent requirement for the purpose of suppressing adjacent channel interferences.Simultaneously,good phase linearity is required instead in order to keep the shape of the pulse when receiving RF-signals from an antenna.Therefore,the study of the flat group delay characteristics of wideband low-noise amplifier has broad prospects and very important significance.This thesis proposes a using transmission line as feedback loops to design a cascode extremely small low noise amplifier with high gain and flat group delay in0.13 um CMOS process at 22-27 GHz.And a method of synthesizing group delay is proposed in the thesis.In addition,High characteristic impedance and high slow wave factor condensed complementary-conducting-strip transmission line(CCS TL)based on the CCS TL that has been proposed.The design method is by changing the transmission line width and the spacing between adjacent transmission lines to adjust the characteristic impedance of the transmission line.It can also further improve the circuit integration.To reduce the chip size for systematic integration,the CCS TL was adopted to design the passive elements that are bulky in RF circuits.With the change of frequency,the characteristic impedance and the slow wave factor of the complementary-strip transmission line approximates to constant,which is the main advantage compared with the traditional microstrip line.The CCS TL is useful for minimization of the chip size the mesh ground plane also provides a good isolation between the circuit and the Si substrate.The thesis uses the transmission line to implement the inductive feedback cascode amplifier to achieve 16.9% group delay variation from 22 GHz to 27 GHz.The transfer function of the second-order all-pass network,derived from the two-port Y-parameter,is applied to synthesize the group delay.A prototype,fabricated in the0.13 ?m CMOS technology,is characterized through the on-wafer testing.Themeasurements show a power consumption of 12 mW from 1.2 V,an amplifier gain of11±0.4 dB,a noise figure(NF)of 5.1±0.4 dB and a group delay of 71 picoseconds(ps)with a variation of ±6 ps from 22 GHz to 27 GHz.From 21 GHz to 27 GHz,the measured input 1-dB compression point(IP1dB)and the input third-order intercept point(IIP3)are higher than-9.2 dBm and +4.2 dBm,respectively.