Design of CMOS based reconfigurable LNA at millimeter wave frequency using active load

Due to increased commercial and scientific applications in millimeter wave (mm wave) band, the development of mm wave transceivers is considered as prominent phase in RFIC design cycle. This paper proposes the design of reconfigurable low noise amplifier (LNA) working at 60 GHz using active load transistor. A single stage source degenerated LNA has been designed to achieve a gain of 8.38 dB and noise figure (NF) of 2.92 dB. The frequency of operation is tuned from 57 to 64 GHz i.e. at millimeter wave. Variation in gain and noise figure are achieved through the design of active load using NMOS transistor. This active load works as reconfiguration network which is subjected to proper bias voltage that yields the highest gain of 8.41 dB and the lower possible gain of 6.9 dB. Similarly the results of NF reaching 2.92 dB as minimum value and on the other end reaching 3.3 dB are observed and presented. That is, reconfigurable performance parameters are gain and NF whose variability is observed to be 17.66 % and 13% respectively. Proper bias voltage is extracted using DC characteristics of load transistor and their results are presented. Design parameter of LNA at millimeter wave frequencies, consideration of noise sources and its equivalent noise voltages, device modeling considering the parasitic effect and choice of LNA configuration have also been discussed.