An X-band four-way combined GaN solid-state power amplifier

• Published in: Journal of semiconductors Vol. 31; no. 1; pp. 58 - 64
• Main Author: 陈炽 郝跃 冯辉 谷文萍 李志明 胡仕刚 马腾
• Format: Journal Article
• Language: English
• Published: IOP Publishing 2010
• Subjects: AlGaN; HEMT器件; X波段; 功率放大器模块; 固态功率放大器; 氮化镓; 混合动力车; 直流偏置电路
• DOI: 10.1088/1674-4926/31/1/015003
• ISSN: 1674-4926

An X-band four-way combined GaN solid-state power amplifier module is fabricated based on a self- developed AlGaN/GaN HEMT with 2.5-mm gate width technology on SiC substrate. The module consists of an Al- GaN/GaN HEMT, Wilkinson power hybrids, a DC-bias circuit and microstrip matching circuits. For the stability of the amplifier module, special RC networks at the input and output, a resistor between the DC power supply and a transistor gate at the input and 3λ/4 Wilkinson power hybrids are used for the cancellation of low frequency self-oscillation and crosstalk of each amplifier. Under Vds = 27 V, Vgs = -4.0 V, CW operating conditions at 8 GHz, the amplifier module exhibits a line gain of 5 dB with a power added efficiency of 17.9%, and an output power of 42.93 dBm; the power gain compression is 2 dB. For a four-way combined solid-state amplifier, the power combining efficiency is 67.5%. It is concluded that the reduction in combining efficiency results from the non-identical GaN HMET, the loss of the hybrid coupler and the circuit fabricating errors of each one-way amplifier.