现在的射频功率计和早期的大有不同。举例来说,热电偶技术的新发展已使功率测量的误差显著降低.要辨别功率计测量和测量仪准确度之间的差别,就要了解功率计器件及其测量技术。因此,先回顾传统的射频功率测量方法是有益处的。首先,热敏电阻是对温度敏感的元件,其阻抗随温度而变。早期的功率计把热敏电阻作为电阻负载来使用。如图1所示,热敏电阻用作惠斯登电桥的一个臂。 The current RF power meter and early different. For example, new developments in thermocouple technology have resulted in significant reductions in power measurement errors, and to discern the differences between power meter measurements and meter accuracy, it is important to understand power meter devices and their measurement techniques. Therefore, it is beneficial to review the traditional RF power measurement methods first. First, a thermistor is a temperature-sensitive component whose impedance varies with temperature. Early power meters used thermistors as resistive loads. As shown in Figure 1, a thermistor is used as one arm of a Wheatstone bridge.