Automated Microwave Tuner System Simplifies Transistor Characterization

Abstract

A new broadband automated microwave tuner system has been developed which is used to characterize transistor impedance, noise figure, and power output. The repeatability, accuracy, and speed provide a major improvement over manually operated tuners, and the broad 1.8 to 18 GHz bandwidth, low loss, wide matching range, and ability to reset to 50 Ohms provide superior performance over previously reported automated tuners. A GPIB controller allows either manual or automated control of one or two tuners. User friendly application software on HP Series 200/300 or the IBM PC allows the tuner impedance to be measured and stored, so contours of constant power, gain, or noise figure can be quickly determined as a transistor is measured. This satisfies a major industry need for a cost-effective, broadband measurement system.