A new method for improving sampling bandwidth of power analyzer

In recent years, increasing energy efficiency has garnered attention worldwide, due to its significant role in several domains. Power analyzers are widely used for power-related parameter calculation and real-time waveform display. However, the sampling rate of the power analyzer is normally relative low. As we know, for some high-frequency signals, if the sampling rate of the power analyzer does not satisfy the Nyquist sampling frequency, it will cause a waste of the analog channel bandwidth resources. Therefore, it is necessary to increase the power analyzer's sampling rate. Equivalent sampling technology can greatly improve the equivalent sampling rate, but there also exist some problems, such as high sampling error and low refresh rate of waveform. In this paper, we describe a new equivalent sampling architecture which is suitable for power analyzer. It can increase the sampling rate of power analyzer to 100MSPS and the sampling bandwidth to 20MHz. What's more, the effect of sampling delay error on waveform distortion can drastically reduced by averaging the multi-frame waveform. For a 20MHz sinusoidal input signal, when we set the average times as 256, then THD+Noise can be reduced to 0.75%, and the ENOB of the sampling system is only 10 bits.