Motion detection apparatus having the ability to determine the direction of motion and range of a moving object

Claim 2

In a motion detection system for detecting movement of an object within a predetermined area, Doppler radar means for generating frequency signals for radiation into said area to produce Doppler frequency signals whenever the frequency signals radiated into said area are reflected off said object, said Doppler radar means being operable to radiate signals alternately at least at first and second frequencies into said area to thereby produce at least a pair of discrete Doppler frequency signals including first and second Doppler frequency signals having a relative phase relationship which is indicative of the range and direction of movement of said object relative to said Doppler radar means, phase detecting means responsive to said first and second Doppler frequency signal for providing first and second output pulses having a relative pulse width relationship that is indicative of the phase difference between said first and second Doppler signals, and output means including first and second pulse width detecting means responsive to said first and second output pulses, respectively, to enable an output to be provided over said output means that is indicative of the direction of movement of said object relative to said Doppler radar means.

Claim 3

A motion detection system as set forth in claim 1 wherein said Doppler radar means includes oscillator-mixer means operable to generate said frequency signals for radiation into said area and for receiving signals reflected back to said Doppler radar means from said area, including reflected signals at said first and second frequencies and said first and second Doppler frequency signals, said oscillator-mixer means being further operable to mix signals at said first and second frequencies with said reflected signals to permit said first and second Doppler frequency signals to be recovered from said reflected signals.

Claim 4

A motion detection system as set forth in claim 2 wherein said oscillator-mixer means includes diode means and control means for controlling said diode means to be operable to generate said frequency signals alternately at said first and second frequencies, whereby said first Doppler frequency signals are produced whenever signals at said first frequency are radiated into said area and said second Doppler frequency signals are produced whenever signals at said second frequency are radiated into said area.

Claim 5

A motion detection system as set forth in claim 3 wherein said control means includes modulating means for providing first and second modulating signals for said diode means, said modulating means having timing means for enabling signals at said first frequency to be generated for radiation into said area for a time sufficient to permit the first Doppler signals corresponding to radiated signals at said first frequency to be received by said diode means while signals at said first frequency are being generated to thereby enable said first Doppler frequency signals to be recovered from reflected signals, and for thereafter enabling signals at said second frequency to be generated for radiation into said area for a time sufficient to permit the second Doppler frequency signals corresponding to radiated signals at said second frequency to be received by said diode means while signals at said second frequency are being generated to thereby enable said second Doppler signals to be recovered from said reflected signals.

Claim 6

A motion detection system as set forth in claim 3 which includes Doppler signal separation means connected to an output of said oscillator-mixer means and controlled by said control means in synchronism with the generation of signals at said first and second frequencies to pass said first Doppler frequency signals to a first input of said phase detecting means and to pass said second Doppler frequency signals to a second input of said phase detecting means.

Claim 7

A motion detection system as set forth in claim 1 wherein said Doppler radar means includes oscillator means for generating said frequency signals for radiation into said area and separate mixer means for receiving reflected signals, including signals at said first and second frequencies and Doppler frequency signals, said mixer means being operable to mix said reflected signals with signals at said first and second frequencies to permit said Doppler frequency signals to be recovered from said reflected signals.

Claim 8

A motion detection system as set forth in claim 6 wherein said oscillator means includes diode means and modulating means for controlling said diode means to generate said frequency siGnals alternately at first and second frequencies, whereby said first Doppler frequency signals are produced whenever signals at said first frequency are radiated into said area and said second Doppler frequency signals are produced whenever signals at said second frequency are radiated into said area.

Claim 9

A motion detection system as set forth in claim 7 wherein said mixer means includes further diode means for receiving said reflected signals and for mixing said reflected signals with signals at said first and second frequencies coupled from said oscillator means to said further diode means to enable said first and second Doppler frequency signals to be recovered from said reflected signals.

Claim 10

A motion detection system as set forth in claim 8 which includes signal separation means connected to an output of said mixer means and controlled by said modulating means to pass said first Doppler frequency signals to a first input of said phase detecting means and to pass said second Doppler frequency signals to a second input of said phase detecting means.

Claim 11

In a motion detection system, Doppler radar means for generating frequency signals for radiation into a predetermined area to produce Doppler frequency signals whenever the frequency signals radiated into said area are reflected off an object moving within said area, said Doppler radar means being operable to radiate signals alternately at first and second frequencies into said area to thereby produce at least corresponding first and second discrete Doppler frequency signals having a relative phase relationship which is indicative of at least the direction of movement of said object relative to said Doppler radar means, Doppler signal processing means including phase detecting means having bistable switching means responsive to said first and second Doppler frequency signals to provide first and second pulses at first and second outputs thereof, the width of one of said pulses being greater than the width of the other one of said pulses whenever said first Doppler frequency signal phase leads said second Doppler frequency signal and the width of the other one of said pulses being greater than the width of said one pulse whenever said second Doppler frequency signal phase leads said first Doppler frequency signal, and pulse width detecting means responsive to said first and second pulses to provide a first output indicating that the object is moving in a first direction relative to said Doppler radar means whenever the width of said first pulse exceeds a predetermined value and to provide a second output indicating that the object is moving in the opposite direction whenever the width of said second pulse exceeds said predetermined value.

Claim 12

In a motion detection system, Doppler radar means for generating frequency signals for radiation into a predetermined area to produce Doppler frequency signals whenever the frequency signals radiated into said area are reflected off an object moving within said area, said Doppler radar means being operable to radiate signals alternately at first and second frequencies into said area to thereby produce at least corresponding first and second discrete Doppler frequency signals having a relative phase relationship which is indicative of at least the direction of movement of said object relative to said Doppler radar means, Doppler signal processing means including phase detecting means having bistable switching means responsive to said first and second Doppler frequency signals to provide first and second pulses at first and second outputs thereof, the width of one of said pulses being greater than the width of the other one of said pulses whenever said first Doppler frequency signal phase leads said second Doppler frequency signal and the width of the other one of said pulses being greater than the width of said one pulse whenever said second Doppler frequency signal phase leads said first Doppler frequency signal, and pulse width detecting means responsive to said first and second pulses to provide a first output indicating that the object is moving in a first direction relative to said Doppler radar means whenever the width of said first pulse exceeds a predetermined value and to provide a second output indicating that the object is moving in the opposite direction whenever the width of said second pulse exceeds said predetermined value.

Claim 13

A motion detection system as set forth in claim 10 wherein said bistable switching means includes flip flop means, said flip flop means being set responsive to one of said Doppler frequency signals to provide said first pulse and said flip flop means being reset responsive to the other one of said Doppler frequency signals to provide said second pulse.

Claim 14

A motion detection system as set forth in claim 11 wherein said Doppler signal processing means further includes first and second signal circuits responsive to said first and second Doppler frequency signals, respectively, to provide set and reset signals, respectively, for said flip flop means, whereby said flip flop means is first set and thereafter reset whenever said first Doppler frequency signal phase leads said second Doppler frequency signal, and alternatively, said flip flop means is first reset and thereafter set whenever said first Doppler frequency signal phase lags said second Doppler frequency signal.

Claim 15

A motion detection system as set forth in claim 12 wherein said first signal circuit includes first amplitude detecting means, responsive to the first Doppler frequency signals which have at least a predetermined amplitude to provide a control signal For effecting the generation of said set pulse and said second signal circuit includes second amplitude detecting means responsive to the second Doppler frequency signals which have at least a predetermined amplitude to provide a further control signal effecting the generation of said reset signal.

Claim 16

A motion detection system as set forth in claim 13 wherein said Doppler signal processing means further includes gating means for passing said first Doppler frequency signals to an input of said first signal circuit and for passing said second Doppler frequency signals to an input of said second signal circuit.

Claim 17

A motion detection system as set forth in claim 13 wherein said first signal circuit includes first pulse shaping means interposed between said first amplitude detecting means and a set input of said flip flop means and responsive to said control signal to provide said set signal for said flip flop means, and said second signal circuit includes second pulse shaping means interposed between said second amplitude detecting means and a reset input of said flip flop means and responsive to said further control signal to provide said reset signal for said flip flop means.

Claim 18

A motion detection system as set forth in claim 10 wherein said pulse width detecting means includes first means connected to said first output of said bistable switching means and enabled to provide said first output whenever the width of said first pulse exceeds a first preselected pulse width value and second means connected to said second output of said bistable switching means and enabled to provide said second output whenever the width of said second pulse exceeds a second preselected pulse width value.

Claim 19

A motion detection system as set forth in claim 16 wherein said pulse width detecting means further includes means for controlling said first and second means to preselect said first and second pulse width values.

Claim 20

In a motion detection system, Doppler radar means for generating frequency signals for radiation into a predetermined area to effect the generation of Doppler frequency signals whenever the frequency signals radiated into said area are reflected off an object moving within said area, said Doppler radar means being operable to radiate signals of at least first and second frequencies alternately in pairs into said area to thereby produce corresponding pairs of first and second Doppler frequency signals, the Doppler frequency signals of each pair having a phase relationship indicative of at least the direction of motion of said object relative to said Doppler radar means, Doppler signal processing means responsive to each pair of first and second Doppler frequency signals to provide a first output signal whenever the first Doppler frequency signal phase leads the second Doppler frequency signal by a predetermined amount and a second output signal whenever the first Doppler frequency signal phase lags the second Doppler frequency signal by at least said predetermined amount, and output means including first indicator means and first signal counting means responsive to a predetermined number of successive ones of first output signals to enable said first indicator means to provide a first indication whenever said object is moving in a first direction relative to said Doppler radar means, and second indicator means and second signal counting measn responsive to a predetermined number of successive ones of second output signals to enable said second indicator means to provide a second indication whenever said object is moving in the opposite direction.

Claim 21

In a motion detection system, Doppler radar means for generating frequency signals for radiation into a predetermined area to effect the generation of Doppler frequency signals whenever the frequency signals radiated into said area are reflected off an object moving within said area, said Doppler radar means being operable to radiate signals of at least first and second frequencies alternately in pairs into said area to thereby produce corresponding pairs of first and second Doppler frequency signals, the Doppler frequency signals of each pair having a phase relationship indicative of at least the direction of motion of said object relative to said Doppler radar means, Doppler signal processing means responsive to each pair of first and second Doppler frequency signals to provide a first output signal whenever the first Doppler frequency signal phase leads the second Doppler frequency signal by a predetermined amount and a second output signal whenever the first Doppler frequency signal phase lags the second Doppler frequency signal by at least said predetermined amount, and output means including first indicator means and first signal counting means responsive to a predetermined number of successive ones of first output signals to enable said first indicator means to provide a first indication whenever said object is moving in a first direction relative to said Doppler radar means, and second indicator means and second signal counting measn responsive to a predetermined number of successive ones of second output signals to enable said second indicator means to provide a second indication whenever said object is moving in the opposite direction.

Claim 22

A motion detection system as set forth in claim 18 wherein said output means further includes first reset means responsive to each of said first output signals to effect the reset of said second signal counting means and second reset means responsive to each of said second output signals to effect the reset of said first counting means.

Claim 23

In an intrusion alarm system fOr detecting movement of an intruder within a predetermined area, Doppler radar means for producing a plurality of pairs of first and second discrete Doppler frequency signals, the Doppler frequency signals of each pair having a relative phase relationship indicative of the range and direction of motion of movement of said intruder relative to said Doppler radar means, phase detecting means responsive to each pair of Doppler frequency signals to provide at least one output pulse having a width proportional to the difference in phase between the first and second Doppler frequency signals of a given pair, pulse width detecting means responsive to the output pulse provided by said phase detecting means to provide a first output whenever the first Doppler frequency signal of a given pair phase leads the second Doppler frequency signal of said given pair by at least a predetermined amount and a second output whenever the first Doppler frequency signal of said given pair phase lags the second Doppler frequency signal of said given pair by at least said predetermined amount, and means responsive to a plurality of successive first output signals to provide an alarm indicating that said intruder is moving in a first direction relative to said Doppler radar means and responsive to a plurality of successive second output signals to provide an alarm indicating that said intruder is moving in the opposite direction.

Claim 24

In an intrusion alarm system fOr detecting movement of an intruder within a predetermined area, Doppler radar means for producing a plurality of pairs of first and second discrete Doppler frequency signals, the Doppler frequency signals of each pair having a relative phase relationship indicative of the range and direction of motion of movement of said intruder relative to said Doppler radar means, phase detecting means responsive to each pair of Doppler frequency signals to provide at least one output pulse having a width proportional to the difference in phase between the first and second Doppler frequency signals of a given pair, pulse width detecting means responsive to the output pulse provided by said phase detecting means to provide a first output whenever the first Doppler frequency signal of a given pair phase leads the second Doppler frequency signal of said given pair by at least a predetermined amount and a second output whenever the first Doppler frequency signal of said given pair phase lags the second Doppler frequency signal of said given pair by at least said predetermined amount, and means responsive to a plurality of successive first output signals to provide an alarm indicating that said intruder is moving in a first direction relative to said Doppler radar means and responsive to a plurality of successive second output signals to provide an alarm indicating that said intruder is moving in the opposite direction.

Claim 25

In an intrusion alarm system, Doppler radar means including oscillator means having diode means for generating frequency signals for radiation into a predetermined area to effect the generation of Doppler frequency signals whenever the frequency signals radiated into said area are reflected off an intruder moving within said area, and modulating means for controlling said diode means to generate frequency signals alternately at first and second frequencies for radiation into said area to produce corresponding first and second discrete Doppler frequency signals which have a relative phase relationship which is indicative of at least the direction of movement of said intruder relative to said Doppler radar means, said diode means being further operable to receive signals, including said Doppler frequency signals and signals at said first and second frequencies, reflected back to said Doppler radar means and to mix signals at said first and second frequencies with said reflected signals to permit said first and second Doppler frequency signals to be recovered from said reflected signals, phase detecting means responsive to said recovered Doppler frequency signals to provide first and second pulses at first and second outputs thereof, the width of one of said pulses being greater than the width of the other one of said pulses whenever said first Doppler frequency signal phase leads said second Doppler frequency signal and the width of the other one of said pulses being greater than the width of said one pulse whenever said second Doppler frequency signal phase leads said first Doppler frequency signal, and pulse width detecting means including first means responsive to the first and second output pulses provided by said phase detecting means to provide a first output whenever one of said Doppler frequency signals phase leads the other one of said Doppler frequency signals for indicating that the intruder is moving in a first direction relative to said Doppler radar means and a second means for providing a second output whenever said one Doppler frequency signal phase lags said other Doppler frequency signal to indicate that the intruder is moving in the opposite direction.

Claim 26

In an intrusion alarm system, Doppler radar means including oscillator means having diode means for generating frequency signals for radiation into a predetermined area to effect the generation of Doppler frequency signals whenever the frequency signals radiated into said area are reflected off an intruder moving within said area, and modulating means for controlling said diode means to generate frequency signals alternately at first and second frequencies for radiation into said area to produce corresponding first and second discrete Doppler frequency signals which have a relative phase relationship which is indicative of at least the direction of movement of said intruder relative to said Doppler radar means, said diode means being further operable to receive signals, including said Doppler frequency signals and signals at said first and second frequencies, reflected back to said Doppler radar means and to mix signals at said first and second frequencies with said reflected signals to permit said first and second Doppler frequency signals to be recovered from said reflected signals, phase detecting means responsive to said recovered Doppler frequency signals to provide first and second pulses at first and second outputs thereof, the width of one of said pulses being greater than the width of the other one of said pulses whenever said first Doppler frequency signal phase leads said second Doppler frequency signal and the width of the other one of said pulses being greater than the width of said one pulse whenever said second Doppler frequency signal phase leads said first Doppler frequency signal, and pulse width detecting means including first means responsive to the first and second output pulses provided by said phase detecting means to provide a first output whenever one of said Doppler frequency signals phase leads the other one of said Doppler frequency signals for indicating that the intruder is moving in a first direction relative to said Doppler radar means and a second means for providing a second output whenever said one Doppler frequency signal phase lags said other Doppler frequency signal to indicate that the intruder is moving in the opposite direction.

Claim 27

An intrusion alarm system as set forth in claim 21 wherein said diode means comprises avalanche diode means operable to generate signals of a predetermined frequency and wherein said modulating means includes further diode means and timing means for providing control signals for controlling said further diode means to modulate the frequency of the sIgnals provided by said avalanche diode means to thereby permit frequency signals at said first and second frequencies to be generated for radiation into said area.

Claim 28

A motion detection system as set forth in claim 22 wherein said further diode means comprises varactor diode means and wherein said timing means comprises control signal generating means for providing first and second control signals at a predetermined rate for controlling said varactor diode means to frequency modulate the frequency output of said avalanche diode means at said predetermined rate.

Claim 29

An intrusion alarm system as set forth in claim 23 wherein said control signal generating means includes means for adjusting the rate of generation of said control signals to enable signals at said first frequency to be generated for a time sufficient to permit first Doppler frequency signals corresponding to radiated signals at said first frequency to be received by said avalanche diode means while said signals at said first frequency are being generated to thereby enable said first Doppler frequency signals to be recovered from reflected signals, and to thereafter enable signals at said second frequency to be generated for radiation into said area for a time sufficient to permit said second Doppler frequency signals corresponding to radiated signals at said second frequency to be received by said avalanche diode means while said signals at said second frequency are being generated to thereby enable said second Doppler signals to be recovered from said reflected signals.

Claim 30

A motion detection system as set forth in claim 21 which includes Doppler frequency signal separation means connected to an output of said oscillator means and controlled by said modulating means in synchronism with the generation of signals at said first and second frequencies to extend the first Doppler frequency signals corresponding to said first radiated frequency to a first input of said phase detecting means and to extend the second Doppler frequency signals corresponding to said second radiated frequency to a second input of said phase detecting means.

Claim 31

A motion detecting system as set forth in claim 21 wherein said diode means of said oscillator means comprises avalanche diode means and wherein said modulating means includes bias means for supplying bias current for said avalanche diode means, said avalanche diode means being responsive to the application of a bias current at a predetermined level to generate frequency signals at a predetermined frequency, said modulating means further including means for controlling said bias means to supply bias current at first and second levels to said avalanche diode means to enable said avalanche diode means to generate frequency signals at asid first and second frequencies.

Claim 32

In an intrusion alarm system for detecting movement of an intruder within an area being protected by said system, Doppler radar means for producing a plurality of pairs of Doppler frequency signals, each pair of Doppler frequency signals including first and second discrete Doppler frequency signals which have a relative phase relationship which is indicative of at least the direction of movement of said intruder relative to said Doppler radar means, phase detecting means, signal separation means including first and second signal circuit means and gating means for gating the first Doppler frequency signal of each pair to an input of said first signal circuit means to enable said first signal circuit means to provide a first control signal for said phase detecting means, and for gating the second Doppler frequency signal of each pair to an input of said second signal circuit means to enable said second signal circuit means to provide a second control signal for said phase detecting means, said phase detecting means including flip flop means having a set input connected to an output of said first signal circuit means and a reset input connected to an output of said second sigNal circuit means, said flip flop means being set by the first control pulses provided by said first signal circuit means to provide a first logic 1 level output at a first output thereof, and a first logic 0 level output pulse at a second output thereof, and said flip flop means being reset by the second control pulses provided by said second signal circuit means to provide a second logic 0 level output pulse at said first output and a second logic 1 level output pulse at said second output, the widths of the logic 1 level output pulses provided at said first and second outputs being indicative of the difference in phase between the first and second Doppler frequency signals of a given pair, and output means responsive to the output pulses provided by said flip flop means to provide a first output whenever the first Doppler frequency signal of a given pair phase leads the second Doppler frequency signals of said given pair by at least a predetermined amount to indicate that the intruder is moving in a first direction relative to said Doppler radar means, and to provide a second output whenever the first Doppler frequency signal of a given pair phase lags the second Doppler frequency signal of said given pair by at least said predetermined amount to indicate that the intruder is moving in the opposite direction.

Claim 33

In an intrusion alarm system for detecting movement of an intruder within an area being protected by said system, Doppler radar means for producing a plurality of pairs of Doppler frequency signals, each pair of Doppler frequency signals including first and second discrete Doppler frequency signals which have a relative phase relationship which is indicative of at least the direction of movement of said intruder relative to said Doppler radar means, phase detecting means, signal separation means including first and second signal circuit means and gating means for gating the first Doppler frequency signal of each pair to an input of said first signal circuit means to enable said first signal circuit means to provide a first control signal for said phase detecting means, and for gating the second Doppler frequency signal of each pair to an input of said second signal circuit means to enable said second signal circuit means to provide a second control signal for said phase detecting means, said phase detecting means including flip flop means having a set input connected to an output of said first signal circuit means and a reset input connected to an output of said second sigNal circuit means, said flip flop means being set by the first control pulses provided by said first signal circuit means to provide a first logic 1 level output at a first output thereof, and a first logic 0 level output pulse at a second output thereof, and said flip flop means being reset by the second control pulses provided by said second signal circuit means to provide a second logic 0 level output pulse at said first output and a second logic 1 level output pulse at said second output, the widths of the logic 1 level output pulses provided at said first and second outputs being indicative of the difference in phase between the first and second Doppler frequency signals of a given pair, and output means responsive to the output pulses provided by said flip flop means to provide a first output whenever the first Doppler frequency signal of a given pair phase leads the second Doppler frequency signals of said given pair by at least a predetermined amount to indicate that the intruder is moving in a first direction relative to said Doppler radar means, and to provide a second output whenever the first Doppler frequency signal of a given pair phase lags the second Doppler frequency signal of said given pair by at least said predetermined amount to indicate that the intruder is moving in the opposite direction.

Claim 34

An intrusion alarm system as set forth in claim 27 wherein said first and second signal circuit means include first and second amplitude detecting means, respectively, said first and second amplitude detecting means being responsive to Doppler frequency signals only in excess of a preselected amplitude for enabling said first and second control pulses to be provided over said first and second signal circuit means.

Claim 35

An intrusion alarm system as set forth in claim 28 wherein said first signal circuit means further includes first pulse shaping means operable when enabled to provide said first control pulse, and said second signal circuit means further includes second pulse shaping means operable when enabled to provide said second control pulse, said first amplitude detecting means being responsive to each first Doppler frequency signal in excess of said preselected amplitude to provide a signal for enabling said first pulse shaping means, and said second amplitude detecting means being responsive to each second Doppler frequency signal in excess of said preselected amplitude to provide a signal for enabling said second pulse shaping means.

Claim 36

An intrusion alarm system as set forth in claim 27 wherein said output means includes first pulse width detecting means enabled whenever at least one of said first logic 1 level output pulses exceeds a predetermined width to provide said first output, and second pulse width detecting means enabled whenever at least one of said second logic 1 level output pulses exceeds a predetermined width to provide said second output.

Claim 37

An intrusion alarm system as set forth in claim 30 wherein said first pulse width detecting means includes first circuit means connected to said second output of said flip flop means and said second pulse width detecting means includes second circuit means connected to said first output of said flip flop means whereby said first circuit means is enabled to provide a further output pulse related to the width of said second logic 1 level output pulse and said second circuit means is disabled whenever said first logic 1 level output pulse exceeds said predetermined width, and said second circuit means is enabled to provide a further output pulse related to the width of said first logic 1 level output pulse and said first circuit means is disabled whenever said second logic 1 level output pulse exceeds said predetermined width, and threshold detecting means including first means enabled to provide said first output whenever the amplitude of the further output pulse provided by said first circuit means exceeds a predetermined value and second means enabled to provide said second output whenever the amplitude of the further output pulse provided by said second circuit means exceeds said predetermined value

Claim 38

An intrusion alarm system as set forth in claim 31 wherein said threshold detecting means includes means for adjusting the threshold value for said first and second means of said threshold detecting means.

Claim 39

An intrusion alarm system as set forth in claim 30 wherein said output means includes alarm indicating means having first counting means connected to an output of said first pulse width detecting means, and second counting means connected to an output of said second pulse width detecting means, said first counting means being enabled responsive to a plurality of successive outputs provided by said first pulse width detecting means to provide a first alarm output and said second counting means being enabled responsive to a plurality of successive outputs provided by said second pulse width detecting means to provide a second alarm output.

Claim 40

An intrusion alarm system as set forth in claim 33 wherein said alarm indicating means includes first and second visual indicating means individually energized by said first and second alarm outputs, respectively, to indicate the direction of movement of said intruder relative to said Doppler radar means.

Claim 41

An intrusion alarm system as set forth in claim 33 wherein said alarm indicating means includes first reset means connected between the output of said second pulse width detecting means and a reset input of said first counting means for providing a reset signal for said first counting means whenever an output is provided by said second pulse width detecting means and second reset means connected between the output of said first pulse width detecting means and a reset input of said second counting means for providing a reset signal for said second counting means whenever an output is provided by said first pulse width detecting means.