Research And Development Of The 800MHz Radio Frequency Power Amplifier

Radio frequency power amplifier (PA) is one of the vital parts in the communication system, its performance has a great influence on the whole system. As the rapid development of communication system in every area, the research and development of the radio frequency power amplifier has been progressing greatly.In the paper, a radio frequency power amplifier is designed, which has a centre frequency 800 MHz, bandwidth 20 MHz, I/O VSWR less than 1.5, output power 1 Watt and gain 10 dB.(1) Transistor is modeled and simulated using ADS simulation software, and the simulation solves the problem that S parameter don' t describe its properties when transistor is on the large-signal. This method reduces plenty of computation and shortens time of design.(2) We analysis the stability of transistor and the matching between input and output, this analysis provides theory foundation for practices.(3) The loss of circuit is reduced by the means of both power synthesis and circuit symmetry(4) Considering the circuit parasitics, proper circuit layout is used for the improvement of the power amplifier stability.Finally, the radio frequency power amplifier designed is made, and then it is debugged and tested. From the testing result, we draw the conclusion that the power amplifier designed reaches expectant design requirement.