What is "zero-order hold"

n. (context mathematics English) A mathematical model of the practical signal reconstruction done by a conventional digital-to-analog converter, describing the effect of converting a discrete-time signal to a continuous-time signal by holding each sample value for one sample interval.

The zero-order hold (ZOH) is a mathematical model of the practical signal reconstruction done by a conventional digital-to-analog converter (DAC). That is, it describes the effect of converting a discrete-time signal to a continuous-time signal by holding each sample value for one sample interval. It has several applications in electrical communication.