Research On Power Amplifier And Frequency Multiplier For Wireless Communication System

With the rapid progress of wireless communication technologies,the wireless communication systems are developing towards multi-band,ultra-high speed and miniaturization.There are higher requirements for the performance of the radio frequency(RF)front-end circuit of the communication system.Power amplifier(PA)and signal source,as the key modules of RF front-end circuit,are supposed to comply with these requirements.Therefore,in this thesis,the broadband high-efficiency PA and millimeter-wave signal source are studied in depth.Firstly,the current status of research on broadband high-efficiency PAs and millimeter-wave monolithic integrated frequency multipliers(FMs)in the last decade or so is summarized in detail,and the shortcomings of these PA and FM circuits are also investigated.Then,a new method is used to design and fabricate a PA covering multiple frequency bands,and two different methods are employed to design two distinct high performance FMs.(1)In order to simplify the design of broadband high-efficiency PAs,this thesis proposes a mixed design strategy.This mixed design strategy is the combination of theory of mixed continuous mode PAs and new method of realizing circuits that satisfy these theoretical impedances.This new method involves impedance frequency modulation which is realized through a one-stage coupler with modified terminals.The mixed design strategy can effectively reduce the complexity and occupation area of the mixed continuous mode class design.Measured results indicate that the implemented PA can deliver saturated output power of 40.2-42.7 d Bm across the frequency range0.4-3.0 GHz,with drain efficiency of between 60.4%and 74.5%and an area of48.3×24.6 mm~2.(2)To address the problems of narrow output bandwidth and poor harmonic suppression of the traditional FM,a single-tube structure with 6-stage cascade is used to achieve a wide bandwidth by applying the quantitative interleaved tuning technique,and the LC resonant network is introduced to improve the circuit harmonic suppression.The joint simulation shows that the eighth harmonic power gain is 12.5-13.5 d B,the1d B bandwidth is 12 GHz,and the harmonic suppression is above 35 d Bc across the output frequency range 94-106 GHz.(3)In view of the complex design of traditional high gain and high harmonic rejection multiplier,the cross-cross type double matching circuit with high harmonic suppression is obtained by simplified real frequency algorithm,which simplifies the design of inter-stage matching circuit without manual tuning to get matching parameters.The SIR open line is introduced to resolve the problem of large capacitance deviation of small capacitors at high frequency.The final output power is increased by using the load-pull technology and a miniaturized power divider is adopted to reduce the layout area.The joint simulation demonstrates that in the input band of 11.5-12.5GHz,the output gain of octapler is 17.2-18 d B,the output gain of doubler is 16.8-17.8d B,and the harmonic suppression of them is above 40 d Bc,and the layout area is2770×1380 um~2.In summary,a mixed design strategy is presented to simplify the design of broadband high-efficiency PAs.The quantitative interleaved tuning technique and LC resonant network are employed to address the problems of narrow output bandwidth and poor harmonic suppression of FMs.The simplified real frequency method is used to simplify the design of high-gain high harmonic suppression FMs.