Automated Impedance Synthesis

Summary

The method of impedance synthesis employed by a load‐pull system plays a central role in establishing its overall performance, particularly the impedance range, operating bandwidth, power capability, harmonic tuning capability, and measurement speed. Active impedance synthesis is based on either the active‐loop or active‐injection architectures. This chapter provides an introductory treatment of automated impedance synthesis methods for load‐pull using including electromechanical passive impedance synthesis and active impedance synthesis, with emphasis placed on internal operation and associated benefits and limitations of each method. Common tuner specifications are introduced, along with associated manifestations of performance impairment. The chapter closes with discussion of advanced methods such as independent harmonic impedance synthesis and sub‐1 Ω impedance synthesis.