Measurement of RF Peak-Pulse Power by a Sampling-Comparison Method

A method is described whereby RF peak-pulse power may be measured by comparison with CW power at the same frequency. Comparison is made by first sampling the power in a small portion of the RF pulse width and subsequently sampling the same portion of the CW signal whose power level is accurately known. Sampling is accomplished with a fast SPDT coaxial solid-state switch synchronized with the RF pulse. A time delay network allows the sample to be taken anywhere along the RF pulse width. Estimated maximum error for peak power levels to 10 kw is 3 per cent. High CW levels are not necessary since the switch is used in conjunction with directional couplers to cover the power ranges of interest.