Safe stopping distance detector, antenna and method

Claim 1

A safe stopping distance detector for a host vehicle, comprising: an oscillator for generating continuous wave electromagnetic radar output signals; a modulator operably coupled to the oscillator to modulate said output signals; a signal processor operably coupled to the modulator to cause the modulator to produce multiple slope output signals from said oscillator, the slopes being produced in multiple pairs, the two slopes in each pair having opposite sign; a transmit antenna adapted to be located for the transmission of radar signals in a predetermined direction; a power splitter electrically connected between the oscillator and the transmit antenna; a receive antenna adapted to be located to receive radar signals emanating from the transmit antenna and reflecting off obstacles; a mixer electrically coupled between the power splitter and the receive antenna for producing a beat frequency for each modulation slope; said signal processor being electrically coupled to the mixer, the signal processor including means for analyzing the beat frequency for each slope to produce a signal for each possible obstacle, mans for matching said signals in successive pairs, means for identifying recurring signals corresponding to real obstacles, means for calculating the distances to said real obstacles, means for determining if said host vehicle can stop within said distances; and means coupled to the signal processor for producing an alarm if the host vehicle cannot stop within said distances.

Claim 16

A method of determining a safe stopping distance between a host vehicle and target objects, the method comprising the steps of: providing a continuous wave, frequency modulated radar device on the host vehicle to transmit and receive radar signals reflected off said objects; modulating said radar signal to produce a plurality of pairs of modulation slopes the two slopes of each pair having opposite sign, and the slopes in successive pairs having different rates in frequency per second; matching the transmitted signal with the received signal to produce beat frequencies for each modulation slope; converting the beat frequencies to digital data; performing a Fast Fourier Transform on the digital data to produce frequency domain data; matching the frequency domain data relating to reach slope to identify recurring frequencies corresponding to target objects; calculating the distances to the target objects and the distance to stop the host vehicle; and emitting an alarm if the distance to a target object is less than the host vehicle stopping distance.

Claim 17

A method of determining a safe stopping distance between a host vehicle and target objects, the method comprising the steps of: providing a continuous wave, frequency modulated radar device on the host vehicle to transmit and receive radar signals reflected off said objects; modulating said radar signal to produce a plurality of pairs of modulation slopes the two slopes of each pair having opposite sign, and the slopes in successive pairs having different rates in frequency per second; matching the transmitted signal with the received signal to produce beat frequencies for each modulation slope; converting the beat frequencies to digital data; performing a Fast Fourier Transform on the digital data to produce frequency domain data; matching the frequency domain data relating to reach slope to identify recurring frequencies corresponding to target objects; calculating the distances to the target objects and the distance to stop the host vehicle; and emitting an alarm if the distance to a target object is less than the host vehicle stopping distance.