Apparatus for detecting relative velocity

An apparatus for producing velocity signals in accordance with the relative velocity between a first and second unit, while both are moving relative to a surface, comprising:

• a radar frequency oscillator for producing output radar frequency signals;
• a horn connected to the oscillator for directing the output radar frequency signals and for receiving return radar frequency signals;
• a return signal splitter connected to the horn for splitting the return signals into two paths;
• a phase shifter connected to the splitter for phase shifting the return signals to sine and cosine signals;
• sine and cosine amplifiers respectively connected to sine and cosine signals for amplifying the sine and cosine signals;
• first and second programmable low-pass filters respectively connected to the sine and cosine amplifiers;
• a velocity determiner connected to one of the amplifiers;
• a threshold circuit connected to the velocity determiner, the threshold circuit having an output;
• a phase detector connected to the first and second programmable low-pass filters;
• first and second outputs connected to the phase detector;
• an analog-to-digital converter connected to the output of the first programmable low-pass filter;
• a dual port RAM connected to an output of the analog-to-digital converter;
• a fast Fourier transform processor connected to the RAM;
• a timing and control unit connected to the converter and to the RAM;
• an address generator connected to the timing and control unit;
• a demultiplexer logic circuit connected to the address generator and to the RAM and to the phase detector;
• and
• an indicator connected to the demultiplexer logic circuit.

An apparatus for producing velocity signals in accordance with the relative velocity between a first and second unit, while both are moving in the same direction relative to a surface, comprising:

• a dual sensing channel Doppler module having a continuous wave signal transmitter and a Schottky barrier mixer cavity which is attached to the first unit and targets the second unit for receiving return signals and removing the continuous wave signals;
• a splitter and phase shifter connected to the mixer cavity for producing first and second phase displaced Doppler signals;
• a velocity determiner connected to one of the Doppler signals;
• a signal processor receiving the first and second phase displaced Doppler signals, the signal Processor having first and second continuously programmable low-pass filters having control inputs connected to the velocity determiner for separately producing first and low-pass second outputs;
• said signal processor being equipped by the velocity determiner for removing around speed Doppler signal and for analyzing the remaining Doppler signal frequency spectrum and producing relative velocity signals from frequencies preselected by the continuously programmable low-pass filter within the Doppler signal frequency spectrum, which preselected frequencies lie outside the range of frequencies corresponding to the velocity of the first unit moving relative to the surface, wherein
• the filtering means are programmable filtering means having a variable frequency limit;
• the signal-processor further contains velocity-determining means for supplying a signal dependent upon the velocity of the first unit moving relative to the surface;
• and
• control means for controlling the frequency limit of the filtering means is controlled in response to the signal dependent upon the velocity of the first unit moving relative to the surface, wherein the velocity-determining means are connected for receiving the Doppler signals and generating therefrom the signal dependent upon the velocity of the first unit moving relative to the surface, wherein
• the signal processor has a plurality of frequency comparison means responsive to a plurality of preselected frequencies below the range of frequencies corresponding to the velocity of the first unit moving relative to the surface;
• and
• an indicator is connected to be triggered by output signals of the frequency comparison means for indicating the Doppler frequency range and conjointly therewith the classification of the velocity at which the first unit approaches the second unit, and wherein the frequency comparison means are phase locked loops.

An apparatus for producing velocity signals in accordance with the relative velocity between a first and second unit, while both are moving in the same direction relative to a surface, comprising a dual sensing channel Doppler module having a radar frequency generator which is attached to the first unit and targets the second unit, the Doppler module having a horn for transmitting an unmodulated continuous wave signal and for receiving the continuous wave signal returning from the targeted second unit with Doppler shift, a splitter and a phase shifter connected to the horn for providing base band phase related Doppler signals, a base band signal processor for receiving the phase related Doppler signals from the Doppler module, wherein the signal processor contains parallel programmable low-pass filters for separately filtering the phase related Doppler signals and for separately passing the base band phase related Doppler signals only up to a frequency limit below a range of frequencies corresponding to velocity of the first unit moving relative to the surface, and wherein the parallel programmable filtering means are parallel programmable filtering means having variable frequency limits, a velocity indicator connected to one of the Doppler signals and to the low-pass filters for supplying a signal dependent upon the velocity of the first unit moving relative to the surface, and control means connected to the means for supplying and connected to the parallel programmable filtering means for controlling the base band frequency limit of the parallel programmable filtering means in response to the signal dependent upon the velocity of the first unit moving relative to the surface, wherein the signal processor contains phase detector direction-sensitive means for detection of phase shift and for producing output signals indicative of whether the targeted second unit approaches or moves away from the first unit, wherein the signal processor further contains means responsive to changes in frequency of the Doppler signal in the aforementioned frequency range, wherein the signal processor further comprises velocity-determining means connected for receiving the Doppler signals and generating therefrom the signal dependent upon the velocity of the first unit moving relative to the surface, wherein the signal processor has a plurality of frequency comparison means responsive to a plurality of preselected frequencies below the range of frequencies corresponding to the velocity of the first unit moving relative to the surface, and an indicator is connected to be triggered by output signals of the frequency comparison means for indicating the Doppler frequency range and conjointly therewith the classification of the velocity at which the first unit approaches the second unit, and wherein the frequency comparison means are phase locked loops.