Mirrored parallel Hammerstein predistortion for multitone generation

The paper discusses the approach tested for digital pre-distortion of radio frequency vector signal generators, where joint mitigation of impairments is considered stemming from the inphase/quadrature modulator, local oscillator, and power amplifier. A predistorter structure, linear in its parameters, was taken and the parameters were estimated by the least-squares method. The proposed method is validated by demonstrating improvement in the performance of the Rohde & Schwarz SMU200 by about 8 dB reduction in mirror-frequency interference, 17 dB reduction in leakage from the local oscillator, and 6 dB improvement in inter-modulation products. Thus, the tested approach is considered useful for several instrumentation and measurement applications.