Design Of Ka Band Power Amplifier MMIC

In an age of explosive growth of information,communication technology has become increasingly mature,and wireless communication has gradually replaced traditional wired communication.The development of wireless communication is inseparable from spectrum resources,but with the increase of network terminals and the popularity of network applications,low-band resources are becoming increasingly saturated.At this time,the millimeter wave band has become a “prime location” and “highway” for wireless communication with its advantages of wide bandwidth and high speed.The Ka band is located at the low end of the millimeter wave,and the research on the Ka-band wireless communication related technology has great development and application prospects.As the core device in the wireless transceiver system,the power amplifier plays a decisive role in the performance of the entire wireless transceiver system.Therefore,how to design a millimeter wave power amplifier with better performance,smaller size and lower cost is of great significance to high-performance wireless communication systems.As a mature of microwave integrated circuit,microwave monolithic integrated circuit is widely used in the millimeter wave band.Compared with the traditional hybrid microwave integrated circuit,the microwave monolithic integrated circuit integrates active and passive components on a dielectric substrate through a semiconductor process,and has a stable circuit structure,high reliability,and long service life.In addition,microwave monolithic integrated circuits are superior to hybrid integrated circuits in terms of power performance and high frequency performance.However,since the microwave monolithic integrated circuit cannot be modified after tape-out,it is a great challenge for designer.Based on current research hotspots and actual engineering requirements,this thesis explores the basic design theory of Ka-band power amplifiers,including evaluation of transistor performance,optimal impedance traction,and stability measures and the design of the matching networks with the 0.15 μm GaAs pHEMT process.Finally,a 32 GHz ~ 36 GHz power amplifier was designed.The amplifier uses a three-stage cascade topology with an output stage of 16 transistors.The electromagnetic simulation results of the chip layout show that over the band of 32 GHz~36 GHz,the output power of 1 dB compression point reaches two watts,the power added efficiency is 22%,the small signal gain in the band above 22 dB,and the input and output return loss are better than 11 dB and 8 dB,the chip size is 2.75 mm × 2.65 mm.Based on the above design,this paper also continues to synthesize it into a larger output power amplifier through the Lange coupler.The operating frequency band is 32 GHz~36 GHz,the in-band power added efficiency is 19%,the small signal gain is 22 dB,the input and the output return loss is both better than 10 dB.In summary,the Ka-band power amplifier designed in this paper has excellent performance and has broad engineering application prospects.