Tunable Low Noise Amplifier by Active Inductance Loading for Zigbee 2.4 GHz Band

Narrow band Low Noise Amplifiers (LNA) use inductors for band selection and input matching to reduce power consumption and reduce thermal noise generation. The LNA amplifies all signals within its fixed band, including blocking signals. This requires a larger dynamic range from the rest of the front end (mixers and analog to digital converters (ADC)). This paper presents a solid state active inductor tunable loading LNA in 0.18 micro m technology that reduces the complexity of the ADC and the baseband digital circuit area in a radio frequency integrated circuit (RFIC), specifically, the LNA is designed for the Zigbee 802.15.4 2.4 GHz PHY band around 2.4GHz. The proposed tunable LNA, consumes 3.9 mW, and provides a gain of 40 dB, with a tunable selectivity around 12 dB. Key-Words: Active tuned inductor, Low Noise Amplifiers, RFIC, Zigbee, 802.15.4, low power, ADC.