60 GHz mixed signal active load-pull system for millimeter wave devices characterization

In this work we present an active load-pull system dedicated to the characterization of mm-wave devices and integrated circuits operating in the frequency band 50-65 GHz, which enables the use of ultra-broadband modulated signals, up to 1 GHz. The system operation is based on the mixed-signal concept and its test-set and up-conversion/down-conversion signal paths are implemented entirely using WR-15 waveguides, providing high accuracy and system stability in the active load-pull configuration. The proposed system allows for real-time CW and modulated signal (i.e., up to 100 MHz) source and load-pull for model validation and linearity characterization, in the entire system bandwidth. Moreover, through the use of a wide-band arbitrary waveform generator and external wideband oscilloscope the system provides the capability for accurate inband signal characterization of integrated circuits with a modulation bandwidth up to 1 GHz. A preliminary set of measurements are presented reporting the capability of the proposed signal to properly control the load reflection coefficient, on a calibration thru, for power levels up to 11dBm in the entire frequency band. Moreover the broadband capability of the system in both up and down conversion is reported by showing the spectrum and time domain signal of a 1 GHz QPSK signal.