S-band Solid State Power Amplifier

The thesis aimed at the requirement of telemetric transmitter, then put forward acomplete scheme of S-band solid-state power amplifier (SSPA) design, and validated itto be feasibility through simulation. A microwave PA with bandwidth of 300 MHz hasbeen developed, and fabricate in a microstrip on a RO4003 substrate. The PA has atypical 7 W power output at 1 dB compression and a 9 W saturated power with morethan 43 dB linear gain, with flatness of±1dB and gain stability less than±1.4dB, aswell as low VSWR less than 1.6:1 at the temperature range from -40℃to 60℃, aPAE of 25% is obtained and better than 45 dBc harmonic rejection performance hasbeen achieved at 300MHz bandwidth around the 1 dB compression points with goodoutside band rejection. High reliability and efficiency, good reproducibility, low VSWRand small size prove this design concept to be a good candidate for telemetrictransmitters.The content of this paper is abstracted as following:The evolved history of SSPA is introduced in ChapterⅠ.In ChapterⅡ, some theories and principles used in analysis and design ofmicrowave PAs are presented.Then ChapterⅢintroduces the full design process of the PA. The PA consists ofthree stages and the first stage amplifier is simulated via Advanced Design System(ADS) software, and the driving stage is implemented by use of a high gain monolithicPA module, the power stage is designed and optimized with partly matched andunmatched GaAs FET power transistors, through the use of DC analysis, load-pull andsource-pull simulation, Harmonic Balance and S-parameter optimization. Then the biascircuits and DC source module with time sequence are designed, and the EMCperformance of the PA's structure is simulated and analyzed with HFSS software.The experimental results and conclusions follow in ChaptersⅣandⅤ.