On-wafer differential noise figure and large signal measurements of low-noise amplifier

An on-wafer measurement technique is proposed to characterize the differential noise figure (NF), 1-dB compression point (P
1dB
) and input third order intercept point (IP3) of low-noise amplifier (LNA). This work successfully extends Friis equation to the generalized two-port case by introducing true differential mode concept. The correlated differential NF is accurately obtained after de-embedding the noise contribution from the interconnections and external components. Details of equations and measurement procedure are reported in this work. A 2.6 GHz differential LNA was tested to demonstrate the feasibility of measurement and showed precise NF compared with other methods. A large signal measurement based on true differential mode stimulus with the same test bench was also performed and presented accurate results.