采用可调谐有源电感的多频段低噪声放大器

A Multiband Low Noise Amplifier Based on Tunable Active Inductor

设计了一种采用可调谐有源电感(TAI)的多频段低噪声放大器(MBLNA)。在放大级中,由电感值及Q值可多重调谐的TAI与电容值可调谐的变容二极管构成选频网络,并结合共射-共基放大电路,实现对不同频段信号进行选择放大。输入级采用带有输入串联电感与发射极电感负反馈的共射放大电路,实现了MBLNA输入阻抗的宽带匹配。输出级采用共射放大电路,在满足输出匹配的同时,再次对信号进行放大,保证了MBLNA的高增益,同时输出级与放大级构成电流复用结构,降低了整体电路功耗。基于WIN 0.2μm GaAs HBT工艺库,利用ADS对MBLNA的主要性能参数进行验证。结果表明,该MBLNA可以在1.9 GHz、2.4 GHz、3.4 GHz、5.2 GHz等多个频段下工作;电压增益S21分别为27.2 dB、25.5 dB、21.6 dB、17.4 dB;噪声系数NF在1.3 dB~5.2 dB之间;输入和输出匹配良好;电路总功耗仅为17.5 mW。

A multiband low noise amplifier(MBLNA) based on high performance tunable active inductor(TAI) was studied. At amplifier stage, the frequency selection network was constructed by the TAIs with tunable inductance and Q value, and by the variodes with tunable capacitance. It could selectively amplify the signals in different frequency bands in conjunction with common-emitter common-base amplifier circuit. At input stage, the common-emitter amplifier circuit with input inductor in series and emitter inductor negative feedback was employed to realize the broadband input matching. At output stage, the common-emitter amplifier circuit was used to meet output matching and high gain of MBLNA. Furthermore, the current reuse of output stage and amplifier stage reduced power consumption of LNA. Based on WIN 0.2 μm GaAs HBT process library, the performance of MBLNA was verified by ADS. The results indicated that the MBLNA could operate at 1.9 GHz, 2.4 GHz, 3.4 GHz and 5.2 GHz, the voltage gain S21 at above bands reached 27.2 dB, 25.5 dB, 21.6 dB and 17.4 dB respectively, the noise figures(NF) were in the range of 1.3 dB~5.2 dB, the good input and output matching was achieved, and the power consumption was only 17.5 mW.