| 摘要 |
<p>PURPOSE:To prevent the erroroneous detection of an object caused by spectrum expanse due to a limited number of observations, by determining a threshold value adapted to the spectrum of a received doppler observation signal to discriminate the impulse corresponding to the object. CONSTITUTION:The reflected electric wave modulated by doppler frequency from an object is converted to a complex video signal S(ti) by a receiver 4 to be inputted to a Fourier converting operator 5 and the Fourier conversion spectrum S(f1) from said operator 5 is applied to a threshold value treating device 7 and a discriminator 6. When (i) is 0, 1, 2... and N is a limited number, a threshold value Ti is calculated and determined on the basis of the formula I at every spectrum S(fi) by the processing device 7 and the spectrum S(fi) due to both of an object signal and a noise signal is discriminated on the basis of a min. threshold value T for deciding the noise and the object signals by the discriminator 6, while by spectrum S(fi+1)S(fi-1), it is discriminated whether S(fi) is real object correspondence or the expanse of spectrum due to a limited number of observations. Therefore, error detection caused by spectrum expanse is prevented.</p> |
