Considerations for Accurately Measuring Pulsed Active Devices

摘要

Understanding device behavior under desired operating conditions is a critical step in the design of any high performance active RF device (e.g., an amplifier or converter). If the component operates in continuous-wave (CW) mode, that characterization can be as simple as measuring its S-parameters using a vector network analyzer (VNA). When it operates in pulsed mode, however, characterization is not so simple. In addition to S-parameters, many other active parameters must be measured in pulse mode. In the case of an amplifier, those parameters include the 1 dB compression (PldB), intermodulation distortion (IMD) and third-order intercept point (IP3). The amplifier's noise figure, higher-order distortion products and harmonics, among other things, may also be characterized depending on its intended application. Because these active parameters are power-dependent, additional considerations are needed to ensure precise characterization. Understanding the changes required to the VNA to support these measurements is also critical.