A low-power 4.5–7.5-GHz low noise amplifier–phase shifter design

Thumbnail Image



Βερροιόπουλος, Δημήτριος-Στυλιανός

Journal Title

Journal ISSN

Volume Title



This thesis presents a low-power RF receiver (Rx) front end that incorporates a low-power Low Noise Ampli er (LNA) and a passive reflection-type Phase Shifter (PS) capable of continuous phase shift, operating in the 4.5–7.5-GHz band. The LNA topology comprises of a cascode stage that increases ampli er gain, while keeping DC power consumption and noise figure (NF) low, followed by an emitter follower which has impedance matching capabilities. The PS consists of two cascaded 3-dB quadrature hybrid couplers with variable LC loads, including, but not limited to varactor diodes. The proposed reflection-type PS load design leads to 360° phase shift range and a maximum insertion loss variation of ±3:3 dB. The LNA consumes 9.6 mW and the overall Rx front end has a gain of 16:25 ± 3:75 dB and noise figure lower than 1.78 dB. The printed circuit board has an area of 21.76 sq cm = 9.42 cm × 2.31 cm.



Low noise amplifier (LNA), Phase shifters, Cascode, Emitter followers, Varactor diode, RF front end, Low power