Non-destructive measurement method of anchor stock length based on electricity standing wave

For common non-destructive measurement methods of anchor stock have problem that vibration wave ca't couple well with the anchor stock, the paper proposed a new non-destructive measurement method of anchor stock legth based on electricity standing wave. The method is based on equivalent principle between transmission line and antenna, and uses standing wave theory of transmission line to measure length of metal anchor stock, that is, scan input signal frequency, when the first minimum voltage of the anchor stock appears, the corresponding signal wavelength is 4 times of anchor stock length, and the anchor stock length can be calculated. The measured result shows that the method has convenient coupling and good measurement result.