A novel active harmonic load-pull setup for on-wafer device linearity characterization

In this paper we present a novel active harmonic load-pull measurement setup devoted to the linearity characterization of on-wafer devices. The proposed setup facilitates independent control of the reflection coefficients at the device under test (DUT) reference planes for the base band (f_IF), fundamental (f₀), and second-order frequency (f_2nd) products. By employing a new concept for the active loads, a small phase variation with frequency of the reflection coefficients at the DUT planes has been achieved. This enables on-wafer device testing with realistic wide-band modulated signals. The applied real-time calibration scheme provides Γ_IN, Γ_S and Γ_L at the DUT for all frequency-mixing products (including base-band). Using the proposed setup, optimum loading conditions for maximum device linearity can be offered on-wafer without any compromise, facilitating a straightforward evaluation of the linearity properties of "new" technology generations.