Guided wave radar liquid indicator

The invention provides a guided wave radar liquid indicator. Two ways of pulse signals are generated through a control and signal processing module, one way pulse signals are converted into narrow pulse signals in an emission signal and sampling signal generating circuit, and act as emission signals and are converted into emission pulse signals in a signal receiving and dispatching module and is transmitted to the liquid surface of tested liquid level through a coaxial cable and a guided wave rod to generate echo signals. The other way pulse signals increase delta t step by step in each narrow pulse signals period in an echo signals sampling time range, step by step delayed sampling signals are obtained and transmitted to the signal receiving and dispatching module, under control of sampling signals, sampling is conducted on the echo signals, due to the fact that the sampling signals and the emission pulse signals have identical frequency, but periods increase step by step, and a maximum time interval between the echo signals and the emission signals is covered, equivalent sampling is achieved to conduct time expansion on the echo signals, and high measurement accuracy can be achieved with low sampling frequency.