Reconfigurable Concurrent Dual-Band Low Noise Amplifier for Noninvasive Vital Sign Detection Applications

Concurrent dual-band reconfigurable low noise amplifier (LNA) for noninvasive detection of human vital signs has been reported in this paper. The reconfigurable output matching network used in this LNA (PHEMT ATF-36163) consists of two shunt stubs terminated by varactor diodes (SMV1232-079LF); while the matching network at input side of the LNA has been designed for fixed dual band operation. The measured characteristics of the fabricated prototype shows that the gain of the LNA varies from 3 dB to 12.2 dB in the frequency range of 2.3-2.5 GHz; while it varies from 9.5dB to 12.9 dB in the frequency range of 4.2-4.6 GHz for a variation in varactor voltages from 0-10V. The simulated value of the Noise Figure of the amplifier is similar to 0.5 dB and 2.5 dB at the centre frequency of the corresponding frequency bands.