A low power variable gain wideband low noise amplifier

A low power variable gain wideband low noise amplifier (LPVG-LNA) was designed in this paper by using active inductor and multiple current reuse circuit structures. At the input stage of LPVG-LNA, a noise canceling structure and an active inductor were employed to reduce noise figure and to realize input matching and gain tuning respectively. At the middle stage, three common-emitter amplifier was utilized to realize high gain. Furthermore, current reuse technique is used at input stage and middle stage respectively to reduce power consumption. At the output stage, an emitter follower was adopted to achieve output matching. Based on WIN 002μm GaAs HBT technology, the proposed LPVG-LNA was verified. The results show that in the frequency range of 1–3GHz, the LPVG-LNA has the gain (S 21 ) of over 37.56dB, the maximum gain tuning range of 4.22dB, the input return loss (S 11 ) of less than −7.06dB, the output return loss (S 22 ) of less than −18.52dB, the noise figure (NF) of less than 4.6dB, the stability factor (k) of over 10.68. The static power dissipation of the LPVG-LNA is less than 35mW under the operation voltage of 5V.