Design Power Amplifier of Basestation and Study on Predistortion System
|School||Liaoning Technical University|
|Course||Communication and Information System|
|Keywords||radio frequency power amplifier(RFPA) load-pull power divider digital baseband predistortion|
Radio frequency power amplifier is the most important device in communication system,and it is the key equipment in the base station system. With the continuous promotion of 3G, designing the high efficiency, high power and high linearity base station amplifier to be a challenge. To design the amplifier to meet the performance, this paper studies the RF power amplifier, including its non-linear, memory effects, design method and linearization techniques, and pay more attention on the design of a power amplifier for base station and two novel structures of dual-band equal power divider .Base station power amplifier is consist of the pre-stage, driver stage and final amplifier, pre-stage and driver stage amplifier design with the method of small-signal design methods which have the balance structure, using load-pull large-signal method design the final amplifier. Simulation and test results show that the base station power amplifier has designed fully meet the high efficiency, high power, and high linearity requirements. Based on the traditional transmission line and the generalized transmission line theory, we successfully design two novel dual-band equal power dividers use even mode-odd mode analysis and they have the excellent performance, and then used it to the circuit to achieve a simple verification confirmed of a balance power amplifier and a Doherty power amplifier performance, results show that the improved performance of the novel structure of amplifier. To get the better performance amplifier, this paper analyzes the linear techniques and gives the digital predistortion system circuit diagram, then uses them to design base station power amplifier, which will be able to improve the amplifier performance and the quality of communication base station system very well, and provide a basis underlying security for the putting into use and promotion of 3G and 4G system.