Design Of RF Broadband Low Noise Amplifier

The continuous development of informatization has raised the people’s demand for wireless communication systems,resulting in higher requirements for the performance and frequency bands of RF front-end chips.The development of wireless communication systems currently involves multiple frequency bands,such as L（1-2GHz）,X（2-4GHz）,C（4-8GHz）,and the currently popular K（18-26.5GHz）and Ka（26.5-40GHz）bands.As a key component of the RF front-end receiver,the research and design of wideband low-noise amplifiers is crucial.This thesis aims to study the design of high-performance low-noise amplifiers covering multiple frequency bands in wireless commun-ication systems,and makes the following contributions to the design challenges of wide bandwidth,low noise coefficient,and high gain:1.Starting with the design requirements of low noise figure and wideband low noise amplifier,a0.1-8.5GHz wideband low-noise amplifier was designed based on the 0.25μm Ga As p HEMT process.To achieve high gain,wide bandwidth band and good return loss performance,a single-stage cascode structure and parallel resistor negative feedback technology were used.In order to compensate for the gain reduction at high frequencies,the peaking inductance gain enhancement technology was used to further expand the bandwidth.The layout simulation results show that within a relative fractional bandwidth of 195%,the highest gain in-band reaches 22d B,with the gain fluctuation not exceeding1d B,the noise figure not exceeding 1.32d B,and the average in-band S₁₁ and S₂₂ less than-14d B.The range of the output 1d B compression point is 15.3-17.8d Bm,and the output third-order interm-odulation point is between 25.5-29.3d Bm.2.In response to the problem that wideband matching is difficult in millimeter-wave band,a low-noise amplifier with the frequency range of 18-40GHz was designed based on 0.13μm Si Ge Bi CMOS process.The low-noise amplifier adopted two-stage differential cascode,and the trans-formers were designed to achieve wideband matching;the bandwidth was extended using an RC negative feedback structure.The layout simulation results show that the average small-signal gain in-band is 21d B,the noise figure is less than 5d B,the average in-band S₁₁ and S₂₂ is-13d B,the output 1d B compression point range is 0-4d Bm,and the power consumption is 80m W.3.In response to the high power consumption and noise coefficient of the previous differential low-noise amplifier,optimization and improvement were made.The low-noise amplifier adopted a single-ended cascode structure,and input matching was achieved using source degeneration induc-tance and T-type matching network to reduce noise coefficient;gain flatness was achieved and power loss was reduced by using a high-pass filtering circuit for inter-stage matching.The layout simulation results show that within the bandwidth of 17-42GHz,the highest gain in-band is 22d B,the noise figure is not exceed 4.3d B,which is optimized by 0.7d B;the range of the output 1d B compression point is4.7-6.6d Bm,which is increased by about 3d Bm;and the power consumption is 22.6m W,which is reduced by nearly 3 times.