초록 ▼

A speed detecting device comprises a comparing circuit for comparing the amplitude of a Doppler signal with a reference amplitude value, and an excluding circuit for excluding a speed signal corresponding to the Doppler signal of the amplitude smaller than the reference amplitude value, whereby the

A speed detecting device comprises a comparing circuit for comparing the amplitude of a Doppler signal with a reference amplitude value, and an excluding circuit for excluding a speed signal corresponding to the Doppler signal of the amplitude smaller than the reference amplitude value, whereby the speed signal corresponding to the Doppler signal of the amplitude larger than a predetermined value. One embodiment of the device further comprises a circuit for selecting and outputting a Doppler signal of the largest amplitude, thereby detecting a vehicle speed based on the Doppler signal of the largest amplitude. Another embodiment of the device comprises a modulator for sequentially changing transmitting frequency of the Doppler radar into a plurality of frequencies at a predetermined period, a detector circuit for detecting each Doppler signal from the Doppler radar in synchronism with the change of the transmitting frequency, a signal processing circuit for forming a Doppler signal corresponding to the transmitting frequency, and a selecting circuit for selecting a Doppler signal of the largest amplitude.

대표청구항 ▼

A speed detecting device having converting means for converting a Doppler signal obtained from a Doppler radar into a corresponding speed indicating signal, comprising: reference signal setting means for setting a reference amplitude value; amplitude detecting means for detecting the amplitude of sa

A speed detecting device having converting means for converting a Doppler signal obtained from a Doppler radar into a corresponding speed indicating signal, comprising: reference signal setting means for setting a reference amplitude value; amplitude detecting means for detecting the amplitude of said Doppler signal; comparing means for comparing said reference amplitude value with the detected amplitude of said Doppler signal in order to identify as a comparison result those portions of said Doppler signal which are detected to be smaller in amplitude than said reference amplitude value; and excluding means for excluding from said speed indicating signal corresponding to said Doppler signal those portions of said Doppler signal which are identified as said comparison result; and wherein said setting means includes means for setting said reference amplitude value based on the relationship between a amplitude of the Doppler signal and the variance of a speed detection error.