Study On The GaN-based Microwave High Efficiency Power Amplifier

As an essential part of the wireless communication system, microwave power amplifier's energy consumption has been widely concerned. During recent years, in order to save energy and reduce the cost of communication, more and more researches have been focusing on improving the efficiency of microwave band amplifier. By the way of harmonic impedance matching, adjusting waveforms of drain current and drain voltage, and suppressing the harmonic power components, the class F and inverse class F have shown great potential in the aspect of improving power amplifiers' efficiency. Compared to other kinds of high efficiency power amplifier, the class F and inverse class F have higher performance and lower requirements for transistors. This is why class F and inverse class F have already become the hotspot in the related research field. Based on the national major special project——research on microwave power amplifier, this paper mainly focuses on microwave band class F/F-1 power amplifier design.The first two chapters described the theories of high efficient class F/F-1 power amplifiers in detail, and also define the significance of the input harmonic control. According to a great number of simulation and design experiences, the author pointed out that for different devices, the best ways of improving the power amplifiers' efficiency are quite different. All these theories provide the basis for design of high efficient power amplifiers.By using the method of input harmonic control, the author designed a 10mm-gate-width C-band power amplifier with high efficiency and high output power, and accomplished the layout level simulation of the power amplifier circuit. The simulation result shows that at the center frequency of 4GHz, the PAE can reach 80%, the peak output power reaches 55 W, the gain is higher than 14 d B, and the PAE maintains 60% above in the 400 MHz frequency range.We also designed and realized an X-band inverse class-F amplifier by using a GaN HEMT device with 1mm gate width and 0.25?m gate length. The layout level simulation of the inverse class-F power amplifier was completed and the results were compared with the traditional class-AB power amplifier——at the expense of a portion of bandwidth, the peak value of PAE was improved by nearly 12 percentage. We also accomplished the manufacturing of the matching microstrip, the assembling and testing of the whole circuit. After tuning, we obtained the 61.7% PAE and 36 d Bm output power at 8.1GHz.