.225 Mhz-512mhz80w The Development Of The Linear Power Amplifier

In modern microwave wireless communication system, the process of information transmission is fleetly developing towards multi-carrier, large capacity and high-speed direction. The higher linearity of radio frequency component is demanded in communication system. Especially the power amplifier, linear level will directly affect the performance of the system.This paper introduced the operating principle of the power amplifier with the working frequency from 225MHz to 512MHz. Advanced Design System(ADS) simulation software helped complete the system simulation and the index allocation of each component. According to the index of components, the product were designed, manufactured and tested. Due to the high power output, wide working band, little fluctuation of the gaining and the high linearization of the power amplifier, it was difficult to design. In this paper, the wideband match, power backspace, degenerative feedback and other technology were used to design. At last, the demand index was obtained.Chapter 1 introduced the feature and application of linear power amplifier, as well as in the actual process of the general use of the indicator.Chapter 2 introduced the basic principle of linear power amplifier, the specific needs assessment indicators, power amplifier classification, as well as the basic principle of design.Chapter 3 discussed the linear power amplifier technology, as in the large-signal conditions, the linear power amplifier indicators, as the paper consider the third-order intermodulation distortion of power amplifier, which is an important indicator, also the difficulty in the design process of linear power amplifier. Then some common and contemporary methods, such as degenerate feedback, predistortion and feed-forward technology that used in designing linear amplifier were introduced.Chapter 4 introduced the simulation and certification process.According to the remand index, before producing the linear power amplifier, ADS simulation software was used to simulate system, allocate index and prove the feasibility of the design.Chapter 5 was the focal point of the paper. This chapter presented the scheme, the function and the index of each module on the basis of mastering the front knowledge. Also the worthy attending problem was described. At the end of this chapter, the tested result and photos were obtained.