Terahertz Multiplier Phase Measurement and Compensation for Power Combination

The phase of the input signal is one of the most important factors determining the efficiency of power combination. To measure the phase performance of terahertz multiplier used in power combination system, a heterodyne phase measurement system based on an antenna-coupled AlGaN/GaN high-electron-mobility transistor is proposed. The signal phases and their differences of four multiplier chains are measured and calculated by this system at the 340 GHz. Moreover, the four-way power combination efficiency with and without phase compensation are simulated in ADS using the measured data. The combination efficiency is greatly improved after phase compensation.