本篇提出一種針對WiFi應用的高效率並兼具溫度補償之互補式金屬氧化物半導體(CMOS)功率放大器， 藉由控制放大器閘極電壓與場效電晶體(FET)具有正溫度系數與電晶體的輸入電壓上升時，汲極電流上升等特性，吾人設計了一種偏壓控制電路可同時提高功率放大器效率當其操作在低輸出功率區並補償當環境溫度上升時所造成的汲極電流衰退。本文中此功率放大器當操作在1dB壓縮點輸出功率為24dBm以台積電0.18um CMOS製程實現，當操作在輸出功率為1dB壓縮點倒推10d時與傳統固定式功率放大器相較可提升效率100%並同時減少因操作溫度上升所造成的增益下降。

This paper presents a high efficiency and temperature compensated CMOS power amplifier that adopts novel adaptive bias control circuit for WiFi application. The bias control circuit is composed of two FET and three resistors. For proposed design, the characteristics that FET has positive temperature coefficient of drain current and the drain current would increases while input power increases. Therefore, the bias control
circuit could simultaneously improves power added efficiency (PAE) at low output power level and compensates the degradation of drain current as ambient temperature rises up. In this paper, a power amplifier implemented by TSMC 0.18um CMOS technology is presented and exhibits output power more than 24dBm. When this amplifier is operated at backing off 10dB from P1dB, PAE improves 100%. Besides, gain degradation is reduced while operating temperature increases.