Simple Technique Employs Vector Network Analyzer to Broadband High Power Amplifiers in Situ

A relatively simple test set-up assists in the broadband tuning of circuits operating at high power levels (i.e. 30 Watts). This procedure also employs a fairly common equipment set. With this method it is possible to optimize Гin (reflection coefficient) as well as Gp (power gain) across the frequency band of interest. This technique employs a network analyzer, which displays Гin or Gp, allowing the effects of circuit tuning to be observed in real time. This dramatically reduces the time it takes to optimize circuit performance. Гin data includes phase information, which can reduce circuit losses seen when transforming past 50 Ohms. This method also allows the user to extend the measurement reference plane into the input matching network.