Research And Design Of Ka Band Limiting Low Noise Amplifiers

As semiconductor process technology and high-speed wireless communication technology have developed rapidly,millimeter wave technology has become increasingly mature.In addition,millimeter-wave communication technology has also had a significant impact on a wide variety of fields in recent years.A low-noise amplifier(LNA)plays a very important role in wireless communication millimeter-wave transmitters,whose key performance parameters include noise figure,chip area,operating bandwidth,gain etc.A low-noise amplifier’s active devices,at present,tend to have low power resistance.The transmitter power is usually extremely high.Due to the proximity of the transmitter and receiver band frequencies,some transmitters will couple their high-power signal to the receiver.However,it is still fatal for the receiver even if this part of the signal accounts for only a small portion of the overall signal from the transmitter.A low-noise amplifier should therefore be designed with a limiter at the front end..A detailed study of the low-noise amplifier with amplitude limitation is presented in the paper,as well as the design of two ka-band amplifiers.The following content summarizes the main work of the research:1)First,conduct in-depth research on the basic theory of designing a limited-range low-noise amplifier,including the relevant theory of limiters,circuit matching methods,design ideas for low-noise amplifiers,etc.This will lay the foundation for the subsequent design of a limited-range low-noise amplifier.2)Second,a limiting LNA design method is discussed in detail,and a PIN/0.15μm-Ga As-p HEMT limiting LNA is designed.A two-stage PIN-diode limiter and a three-stage robust common source(CS)LNA are codesigned and properly matched.The operating frequency ranges between 30 and 36 GHz.Over the entire frequency range,the noise figure is 1.8-2.5 dB,the small-signal gain is 18.5 ± 0.5 dB,and the DC power is 72 m W.Limiting LNAs have a chip size of only 2.1 mm × 1.0 mm,which makes them suitable for use in phased array radar systems.3)Last,a limiting LNA based on PIN/0.15μm-Ga As-p HEMT technology has been designed.To improve the noise performance and the input-matching of the limiter-LNA,a novel limiter design method with the modified lossy TL model is presented.The design can be used in millimeter-wave radar systems operating at frequencies between 27 GHz and 35 GHz.This circuit has a measured noise figure of less than 2.4 dB,an OP1 dB greater than 12 dB,an average gain of 20 dB,and a gain flatness of ±0.7 dB.