Automated one-port impedance measurements on SAW devices with RF pulses

A reflectometer-based system controlled by a desk-top computer has been developed for measuring one-port impedances of surface acoustic wave (SAW) devices. Both CW and pulsed RF signals may be used, because the system allows for the gating-out of spurious signals due, for example, to reflections. Measurements made on SAW devices and dummy loads in the 50-500-MHz range are comparable to the same measurements made on a commercially available manually operated RF impedance bridge (General Radio model 1607-A); it has the added advantage of being fully automatic in its operation and capable of faster measurements.