To solve the mis-action problem of a certain frequency modulation（FM） fuze

we developed an experiment system for ultra-wide band（UWB） irradiation

and performed fuze experiments. Moreover

we analyzed the security effect of UWB on FM fuze

and confirmed the failure mechanism. Theoretical analysis and experimental results show that UWB can make the FM fuze mis-action. The higher the repetition frequency is

the stronger the interference ability of UWB will be. At 100 k V/m field strength

the firing rates of the repetition frequency in single

10 Hz

20 Hz and 50 Hz states are 20%

30%

50% and 80%

respectively. The failure mechanism is that the energy of UWB couples in the antenna and the shielding column directly

leading to the voltage fluctuation of the commonality ground. The changing voltage

which has a higher voltage changing rate value than the critical value of silicon controlled rectifier（SCR）

will transmit to the power supply port of the executing circuit

making the mis-working of SCR

then the fuze will mis-act.