JPH05172942A - Doppler type object detecting device - Google Patents

Abstract

PURPOSE:To obtain a Doppler type ultrasonic object detecting device which is constituted in such a way that the same output result as a ternary signal can be obtained even when only binary signals can be inputted to an integration circuit. CONSTITUTION:A transmitter-receiver 31 sends ultrasonic waves of a fixed frequency and receives reflected waves from a space to be monitored. A pair of Doppler signals D1 and D2 which are beat components having a prescribed phase difference between them is obtained from the signals received by the transmitter-receiver 31 and inputted to an arithmetic and control section 40. The section 40 decides a quadrant from the combination of polarities of the signals D1 and D2. When the decided quadrant continuously changes in the same direction, the section 40 outputs binary transition signals and an integration circuit 37 integrates the signals. When the output value of the circuit 37 exceeds a prescribed range, a detect signal is outputted to a drive circuit 38. When the transition signal is not outputted, a pulse signal having a 50% duty ratio is inputted to the circuit 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention continuously transmits an ultrasonic wave of a predetermined frequency to a surveillance space, and based on the frequency shift of a reflected wave generated by a moving object existing in the surveillance space, The present invention relates to a Doppler type object detection device for detecting the presence.

[0002]

2. Description of the Related Art Conventionally, as a Doppler type object detection device of this kind, ultrasonic waves of a predetermined frequency are continuously transmitted as a detection wave to a monitoring space, and when the object moves in the monitoring space, the Doppler effect is generated. There is provided a device that detects the presence of a moving object by detecting the frequency shift of the generated reflected wave (Japanese Patent Laid-Open No. 55-63774, U.S. Pat. No. 3,432,855, etc.).

FIG. 6 shows an example of this type of Doppler type object detection apparatus, in which a transmission signal output from an oscillation circuit 10 is input to a transmission device 1 equipped with an ultrasonic transducer and transmitted. The ultrasonic wave is transmitted from the wave device 1 to the monitoring space, the reflected wave is received by the wave receiver 2 equipped with the ultrasonic transducer, converted into the received signal Ein, and monitored based on the received signal Ein. It is configured to determine the presence or absence of a moving object in the space.
The received signal Ein is input to the mixers 21a and 21b and mixed with the mixed signals Ex and Ey having the same frequency as the transmitted signal. One mixed signal Ey is input to the mixer 21b through the phase shift circuit 22 so that the phases of the two mixed signals Ex and Ey are different by 90 °. Therefore, a pair of Doppler signals E and E'having different phases, which are beat signals having a frequency difference between the transmitted signal and the received signal, are obtained from the mixers 21a and 21b.

Both Doppler signals E and E'are bipolar and
After being amplified through the amplifier circuits 23a and 23b, respectively, they are converted into binary axis code signals X and Y corresponding to the polarities of the Doppler signals E and E'by the binarization circuits 24a and 24b. The axis code signals X and Y are set to, for example, H level if the Doppler signals E and E'have positive polarity and L level if they have negative polarity. By using the two-axis code signals X and Y, it is possible to determine in which quadrant the received signal Ein exists in the vector plane having the intermediate signals E and E'as basic axes. Therefore, in order to determine in which quadrant the received signal Ein exists based on the combination of the axis code signals X and Y, the axis code signals X and Y are input to the quadrant detection circuit 25. Since the axis code signals X and Y each have two values, a total of four types of combinations can be obtained, and the quadrant detection circuit 25 outputs four types of quadrant signals I to IV corresponding to these combinations. Here, the quadrant detection circuit 25 operates only when the amplitude of the intermediate signal E detected by the level detection circuit 30 is equal to or higher than a predetermined level.

The quadrant signals I to IV are input to the quadrant transition direction detection circuit 26. The quadrant transition direction detection circuit 26 outputs a binary transition signal according to the direction of change when the quadrant changes based on the quadrant signals I to IV. It is configured to hold the output value until ~ IV is exhausted. That is, it is determined whether the direction in which the quadrant changes rotates to the left or right around the origin depending on whether the object approaches or moves away. Therefore, depending on the direction of change in the quadrant, a binary value of H level and L level is set. The signal of is output. The output of the quadrant transition direction detection circuit 26 is input to the integration circuit 27, and the integration result is the threshold circuit 28.
Is compared with a predetermined threshold value set to. Here, a voltage that is ½ of the power supply voltage is constantly input to the integrating circuit 27, and when the transition signal is not generated, the integrating circuit 27
Is configured so that the output value of is equal to one half of the power supply voltage. That is, the quadrant transition direction detection circuit 26 outputs a ternary output. Further, the threshold circuit 28 is set with a first reference voltage which is smaller than that and a second reference voltage which is larger than the half of the power supply voltage.
When the input signal to 8 is equal to or lower than the first reference voltage or equal to or higher than the second reference voltage, the detection signal is output.

According to the above configuration, when the transition signal is not output, the input to the threshold circuit 28 is 2 of the power supply voltage.
That is, the detection signal is not output from the threshold circuit 28. On the other hand, when the transition signal in which the quadrant changes in the same direction is generated a predetermined number of times continuously within a predetermined time, the output value of the integrating circuit 27 is equal to or lower than the first reference voltage set in the threshold circuit 28 or the second reference voltage. As described above, the detection signal is output from the threshold circuit 28. When the detection signal is output from the threshold circuit 28, the drive circuit 29 drives a load such as an alarm device.

[0007]

By the way, in recent years, since microprocessors have become available at low cost, the quadrant detecting circuit 25 and the quadrant transition direction detecting circuit 2 are now available.
It is conceivable to configure 6 and the like using a microprocessor. If a microprocessor is used, there is an advantage that a function as a hardware can be added and a function can be easily made high while simplifying the configuration as hardware. By the way, CM
Since the output form of the microprocessor using the OS is open drain, it is possible to output a binary signal of H level and L level by connecting a pull-up resistor. It is impossible to obtain a half output. If such a three-value output is not obtained, the output value of the integrating circuit 27 between the first reference voltage and the second reference voltage set in the threshold circuit 28 when the transition signal is not output. There is an inconvenience that it cannot be set within the range.

An object of the present invention is to solve the above-mentioned problems. Even if the output form is open drain, the integrated value can be set within the range of upper and lower thresholds when the transition signal is not output. The present invention is intended to provide a Doppler type object detection device.

[0009]

In order to achieve the above object, in the invention of claim 1, a transmitting means for continuously transmitting an ultrasonic wave of a constant frequency to the monitoring space, and an ultrasonic wave from the monitoring space. A receiving means for receiving the received wave and outputting a received wave signal, and the receiving wave frequency and the transmitting wave frequency by mixing the receiving wave signal with a pair of mixed signals having the same frequency as the transmitting wave frequency but different phases from each other. According to the quadrant in which the receiving signal exists in the vector plane with the pair of Doppler signals output from the mixing unit as the basic axis, and the mixing unit that outputs a pair of Doppler signals that have a frequency difference of When the quadrant detected by the quadrant detection means changes, a quadrant detection means for outputting a quadrant signal and a transition signal of two levels depending on the direction of change are obtained during a period in which a Doppler signal whose amplitude is equal to or higher than a predetermined level is obtained. Between the quadrant transition detecting means that outputs continuously until the quadrant changes, an integrating means that integrates the output of the quadrant transition detecting means, and an output value of the integrating means between an upper threshold value and a lower threshold value that are preset. A threshold value means for generating a detection output when the value is out of the range, and a pulse signal with a constant duty ratio is integrated so that the output of the integrating means becomes an intermediate level between the two levels of the transfer signal during the period when the transfer signal is not output. The pulse generating means for inputting to the means is provided.

According to the second aspect of the present invention, when the quadrant transition detecting means changes to a quadrant that is not adjacent when the quadrant detected by the quadrant detecting means changes, the level is opposite to the level when the quadrant last changed. The level transition signal is continuously output until the next quadrant changes. According to the invention of claim 3, when the phase difference between both Doppler signals is a predetermined difference or more with respect to the normal phase difference, noise determining means for determining the Doppler signal due to noise is provided, and the noise determining means is
The pulse generating means is activated when no phase difference is detected in both Doppler signals.

According to another aspect of the present invention, the noise determining means determines that noise is received when the state in which the phase difference between both Doppler signals is within a predetermined range from the normal phase difference continues for a predetermined time or more. The noise determining means activates the pulse generating means when detecting the noise. According to the fifth aspect of the invention, the noise notifying means for notifying that the noise is detected based on the determination result of the noise determining means is provided.

[0012]

According to the first aspect of the present invention, when the transfer signal is not output from the quadrant transfer detecting means, the output of the integrating means becomes an intermediate level between the two levels of the transfer signal. The ratio pulse signal is input to the integrator, and even when a component that can output only a binary signal is used, the output value of the integrator is set to the threshold when the transition signal is not output. It can be set within the range between the upper threshold value and the lower threshold value. By adopting such a configuration, CM
It is possible to provide a high-performance Doppler type object detection device with a low power consumption and a simple structure by using a microprocessor including an OS.

The structures of claims 2 to 5 are specific structures of high functionality capable of preventing erroneous recognition of noise. According to the configuration of claim 2, when the quadrant changes in a jump without continuously changing, it is determined that the change in the quadrant is due to noise, and the level opposite to the level when the quadrant last changed. The output value of the integrating means cannot be increased or decreased by alternately inverting the input value to the integrating means while such noise continues, and as a result, it is set in the threshold means. The range between the upper threshold and the lower threshold cannot be exceeded. That is, no detection output is obtained for noise that causes a dramatic change in the quadrant, and it is possible to prevent erroneous recognition that there is an object in the monitoring space.

According to the third aspect of the invention, when the phase difference between both Doppler signals is a predetermined difference or more with respect to the normal phase difference, it is determined to be noise, and the pulse generating means is operated, so that the commercial When a Doppler signal that is substantially in phase or in phase with each other is generated under the influence of a power source or the like, the transition signal is prevented from being output, and misidentification due to this kind of noise can be prevented.

According to the structure of claim 4, when the state in which the phase difference between the two Doppler signals is within a predetermined range from the normal phase difference continues for a predetermined time or more, the Doppler signal generated by the movement of the person is not detected. However, by determining that the Doppler signal is generated due to the presence of a device that generates ultrasonic waves, it is possible to prevent erroneous recognition by ultrasonic wave generating devices existing in the surroundings.

According to the fifth aspect of the invention, since the noise notifying means for notifying that the noise is detected based on the judgment result of the noise judging means is provided, the occurrence of noise can be recognized.

[0017]

1 is a block diagram showing the overall construction of a Doppler type object detection apparatus. The transmission and reception of ultrasonic waves to and from the monitoring space are performed through a wave transmitter / receiver 31 equipped with an ultrasonic transducer. That is, a transmission signal having a constant frequency (for example, 40 kHz) is output from the arithmetic control unit 40 including a microprocessor using CMOS, and this transmission signal is input to the transducer 31 after being amplified by the amplifier circuit 32. , Is continuously transmitted to the monitoring space as ultrasonic waves. As shown in FIG. 2, the arithmetic control unit 40 includes a clock generation unit 41 that generates a clock signal with a constant period, and obtains a transmission signal by dividing the clock signal by a frequency division unit 42.

On the other hand, ultrasonic waves from the monitoring space are transmitted and received by the transmitter / receiver 3
It is converted into a received signal by 1. That is, the wave transmitter / receiver 31 serves as both a wave transmitting means and a wave receiving means. Here, when a moving object exists in the monitoring space, the frequency of the reflected wave by the moving object deviates from the transmission frequency due to the Doppler effect, so that a slight beat component is generated in the transmission signal. Frequency Delta] f of the beat component, the transmit frequency f _0, the moving speed of the moving object v, when the speed of sound is is c, can be expressed as Δf = (2v / c) · f 0.

The received signal output from the wave transmitter / receiver 31 is input to the mixer circuit 33 and the amplifier circuit 35 together with the input signal to the wave transmitter / receiver 31. A mixed signal having the same frequency as the transmitted signal obtained by passing the transmitted signal through the phase circuit 36 but having a phase difference of 180 ° is input to the mixer circuit 33 and mixed with the received signal from the transmitter / receiver 31. The signals are mixed with each other, and the obtained beat component is input to the amplifier circuit 34. Each of the amplifier circuits 34 and 35 outputs a bipolar Doppler signal by performing envelope detection to detect the beat component of the input signal, amplifying the beat component, and further clipping. Here, the amplifier circuit 34 outputs the Doppler signal D ₁ corresponding to the beat component obtained by mixing the mixed signal having the phase difference of 180 ° with respect to the transmitted signal by the mixer circuit 33, and the amplifier circuit 3
From 5, a Doppler signal D ₂ corresponding to the beat component obtained by mixing the transmitted signal and the received signal is output. Therefore, for a moving object, a pair of Doppler signals D ₁ and D ₂ whose phases are different from each other by 90 ° are obtained. That is, the wave transmitter / receiver 31, the mixer circuit 33, the amplifier circuits 34 and 35, and the phase circuit 36 constitute a mixing means. As shown in FIG. 3, the phase of the Doppler signal D ₁ advances 90 ° with respect to the Doppler signal D ₂ when the object approaches, and the phase delays 90 ° when the object moves away. The Doppler signals D ₁ and D ₂ are input to the arithmetic control unit 40.

The arithmetic control unit 40 is provided with a quadrant detection unit 43, which receives the Doppler signals D ₁ and D ₂ within a vector plane whose basic axes are based on the Doppler signals D ₁ and D _2. A quadrant signal corresponding to the quadrant in which the wave signal exists is output. That is, since the Doppler signals D ₁ and D ₂ are clipped, they become rectangular wave-shaped signals with respect to the beat component, as shown in FIGS. 3A and 3B. Four types of quadrant signals can be obtained by combining the polarities of D ₁ and D ₂ . Now, set the upper limit level of the Doppler signals D ₁ and D ₂ to 1,
As the lower limit level 0, for the combination of Doppler signals (D ₁ , D ₂ ), (1, 1) is the first quadrant,
(0,1) is the second quadrant, (0,0) is the third quadrant, (1,
0) is defined as the fourth quadrant. Based on this regulation, the quadrant detector 43 outputs four types of quadrant signals.

On the other hand, the Doppler signals D ₁ and D ₂ are also input to the phase difference detecting section 44, and the phase difference between both Doppler signals D ₁ and D ₂ is also detected. Here, since the inputs to the quadrant detection unit 43 and the phase difference detection unit 44 are sampled at a constant cycle (for example, 1 msec) synchronized with the clock signal, the quadrant detection unit 43 and the phase difference detection unit are sampled for each sampling cycle. The output from the detection unit 44 is obtained. Therefore, the phase difference detecting unit 44 detects the phase difference by the difference between the number of times of sampling when both Doppler signals D ₁ and D ₂ have the same polarity and the number of times of sampling when they have different polarities. Now, the phase difference between the Doppler signals D ₁ and D ₂ is 90 °, and the Doppler signal D 1
Assuming that the period of ₁ and D ₂ is about 16 msec, the number of samplings of the same polarity and the different polarity is 7 times (rising and falling are not counted). On the other hand, when the period T of the Doppler signals D ₁ and D ₂ is about 16 msec and the phase difference ΔW is considerably smaller than 90 °, as shown in FIG. The ratio of the sampling periods of different polarities may be 1. In this way, the phase difference can be determined based on the number of times of sampling.

The quadrant signal output from the quadrant detector 43 is the two Doppler signals D ₁ , detected by the phase difference detector 44.
It is input to the output unit 46 through the noise determination unit 45 that determines whether or not it is noise based on the phase difference of D ₂ . The noise determining unit 45 regards the phase difference detected by the phase difference detecting unit 44 as noise when the phase difference is equal to or more than a predetermined value with respect to the normal phase difference (that is, 90 °), and does not pass the quadrant signal. .. For example, if the phase difference is less than 70 ° or 1
If it is larger than 10 °, it is regarded as noise. Such a noise determination method is effective when the Doppler signals D ₁ and D _{2 that} are in-phase or in anti-phase are obtained due to the influence of the commercial power supply.

The output section 46 functions as a quadrant transition detecting means, and detects the change of the quadrant based on the quadrant signal when noise is not detected by the noise judging section 45. That is, when the quadrant changes, two levels (H level and L
Output a transition signal which is a level (level) signal. The transition signal is output when the quadrant changes, and is kept at the same level until the next quadrant change or the Doppler signals D ₁ and D ₂ fall below a predetermined level. Therefore, when the object is moving in the same direction, quadrant changes in the same direction occur one after another, and a signal of one of two levels is output as shown in FIG. 3C. become. In addition, the output unit 46 includes the clock generation unit 41 to the frequency division unit 47.
For example, a pulse signal having a duty ratio of 50% at 1 kHz is input, and the pulse signal is output when the transition signal is not generated. That is, the clock generator 41 and the frequency divider 47 function as a pulse generator. Further, the output unit 47, assuming that noise is input, inverts the transition signal even when the quadrant changes, if the change in the quadrant does not have continuity. That is, as shown in FIG. 5, the quadrant is I
If it changes to → II, the next quadrant should be III or I, but here there is a leap like II → IV. When such a leap occurs, it is regarded as noise,
It is designed to generate a transition signal of the opposite level to that when the quadrant change occurred last time. In FIG. 5, II → I
Since there is a leap such as V → II, if the L level is first, the transition signal changes to the H level, then the L level.

The output signal from the output section 46 is an integrating circuit 37.
Entered in. The integrating circuit 37 integrates the transition signal and the pulse signal output from the output unit 46. Therefore, when there is no moving object in the monitoring space and no transition signal is generated, the output of the integrating circuit 37 becomes one half of the power supply voltage Vcc, as shown in FIG. In addition, when the object approaches or moves away and the quadrant changes continuously within a predetermined time, the integrating circuit 3
The output level of 7 becomes H level or L level. Although not shown in the figure, the arithmetic control unit 40 is provided with a threshold value section that sets an upper threshold value L ₁ and a lower threshold value L ₂ for the output value of the integration circuit 37, and the output value of the integration circuit 37 is used as the threshold value section. When it goes out of the range between the upper threshold L ₁ and the lower threshold L ₂ which have been set, as shown in FIG.
The alarm device and the load circuit are driven.

According to the above configuration, when the transition signal is not generated, a pulse signal having a constant duty ratio is input to the integrating circuit 37 so that the output value of the integrating circuit 37 becomes the upper threshold L ₁ and the lower threshold L. _It is within the range of ₂ . Therefore, as shown in FIG. 3C, it is not necessary to input three values to the integrating circuit 37, and the CM
It becomes possible to use a microprocessor using an OS. Further, when the change of the quadrant in the output section 46 jumps, it is regarded as noise and the level of the transfer signal is inverted. Therefore, the input value to the integrating circuit 37 is inverted from that when the quadrant was changed last time, and the input value is changed. _They are canceled out, and the integrated value is less likely to fall outside the range of the upper threshold L ₁ and the lower threshold L ₂ . As a result, the probability of false recognition of noise can be reduced. Further, the noise determination section 45 is provided so as to detect the phase difference between the Doppler signals D ₁ and D ₂ and prevent the quadrant signal from being input to the output section 46 when the phase difference is small. Therefore, noise due to the influence of the commercial power source exists. In this case, the transition signal is prevented from being output by not inputting the quadrant signal to the output section 46, which also reduces the probability of false recognition of noise.

(Embodiment 2) In the present embodiment, the noise judging section 45 uses not only the phase difference but also the duration for judging the noise. That is, even when the Doppler signals D ₁ and D ₂ having a phase difference close to the regular phase difference (that is, 90 °) are generated by the reflected wave from the moving object, the Doppler signals D ₁ and D ₂ are generated from another human body detection sensor or the like. This may be due to factors such as ultrasonic waves that are generated, noise from the outside, and device failures. Since the frequencies of the ultrasonic waves generated from the external device are not unified, when the difference between the ultrasonic waves transmitted from the transducer 31 is small, the Doppler signals D ₁ and D ₂ having a phase difference close to 90 ° are generated. It is output. On the other hand, when it is used as a warning sensor or the like to detect a human, it is sufficient to set a range of at most 10 m as a monitoring space, so that the change of the quadrant with respect to the detection target continues for a long time. Is unthinkable.

In view of the above circumstances, when the state in which the quadrants of the Doppler signals D ₁ and D ₂ change in the same direction continues for a predetermined time or longer, the reflected wave from the target detection target is continued. If not, it stops the generation of the transition signal. Needless to say, the pulse signal is input to the integration circuit 37 when the generation of the transition signal is stopped. Here, it is sufficient to set the time used for the determination to such a time that a person can keep moving in one direction indoors, but it is necessary to detect the ultrasonic waves continuously generated from other devices. If the purpose is, it may be set to 1 minute or more. Other configurations are similar to those of the first embodiment.

(Embodiment 3) In the present embodiment, when noise is detected, its purpose is to notify. That is, when noise is detected by the noise determination unit 45 or the output unit 46, information indicating that noise has been detected is output from the arithmetic control unit 40, and the notification means is driven based on this information.

Specifically, when there is no moving object, a pulse signal of 1 kHz is output from the output unit 46, and a pulse signal of 100 Hz is output from the output unit 46 for noise. A frequency discriminator is provided outside the arithmetic and control unit 40 to discriminate between 1 kHz and 100 Hz output, and when a pulse signal is 100 Hz, a display means such as a light emitting diode is made to blink. Further, the noise detection signal may be directly output from the arithmetic control unit 40 to blink the display means. By notifying such noise, it is possible to notify that there is interference with other devices, and it becomes easy to take measures such as changing the installation place so as not to cause interference. Other configurations are similar to those of the first embodiment.

[0030]

According to the first aspect of the present invention, when the transition signal is not output from the quadrant transition detection means, the output of the integration means is set to an intermediate level between the two levels of the transition signal, and the pulse generation means keeps constant. Since the pulse signal of the duty ratio is input to the integrator, and the component that can output only the binary signal is used, the output value of the integrator is set to the threshold value when the transition signal is not output. It is possible to set within the range between the upper threshold value and the lower threshold value set to. By adopting such a configuration,
It is possible to provide a high-performance Doppler type object detection device with a low power consumption and a simple configuration using a CMOS microprocessor.

According to the second aspect of the invention, when the quadrant does not change continuously but jumps and changes, it is determined that the change in the quadrant is due to noise. What is the level when the quadrant changes last time? Since the transition signal of the opposite level is output, the input value to the integrating means is alternately inverted while such noise continues, so that the output value of the integrating means cannot be increased or decreased, resulting in the threshold value means. Therefore, the range between the upper threshold value and the lower threshold value set in the above cannot be exceeded. That is, there is an advantage that a detection output is not obtained for noise that causes a rapid change in the quadrant, and it is possible to prevent erroneous recognition that there is an object in the monitoring space.

According to a third aspect of the present invention, when the phase difference between the two Doppler signals is a predetermined difference or more with respect to the normal phase difference, it is determined that the noise is noise, and the pulse generating means is operated, so that the commercial When a Doppler signal that is in phase or in phase is generated due to the influence of the power supply,
There is an advantage that the transfer signal can be prevented from being output, and erroneous recognition due to this kind of noise can be prevented.

According to a fourth aspect of the present invention, when the state in which the phase difference between the two Doppler signals is a predetermined difference or less with respect to the normal phase difference continues for a predetermined time or more, the Doppler signal generated by the movement of a person is not detected. However, by determining that the Doppler signal is generated due to the presence of a device that generates an ultrasonic wave, there is an effect that it is possible to prevent erroneous recognition by an ultrasonic wave generating device that is present in the vicinity.

According to the invention of claim 5, since the noise notifying means for notifying that the noise is detected based on the judgment result of the noise judging means is provided, it is possible to recognize the occurrence of the noise. is there.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment.

FIG. 2 is a schematic configuration diagram illustrating an arithmetic control unit according to the first embodiment.

FIG. 3 is an operation explanatory diagram of the first embodiment.

FIG. 4 is an operation explanatory diagram of the first embodiment.

FIG. 5 is an operation explanatory diagram of the first embodiment.

FIG. 6 is a block diagram showing a conventional example.

[Explanation of symbols]

 31 wave transmitter / receiver 32 amplification circuit 33 mixer 34 amplification circuit 35 amplification circuit 36 phase shift circuit 37 integration circuit 38 drive circuit 40 arithmetic control unit 41 clock generation unit 42 frequency division unit 43 quadrant detection unit 44 phase difference detection unit 45 noise determination unit 46 Output section 47 Frequency division section

Claims (5)

[Claims] 1. A transmitting means for continuously transmitting ultrasonic waves of a constant frequency to a monitoring space, a receiving means for receiving ultrasonic waves from the monitoring space and outputting a received signal, and a transmitting frequency. Mixing means for outputting a pair of Doppler signals having a frequency difference between the reception frequency and the transmission frequency and having different phases by mixing a pair of mixed signals having the same frequency but different phases with the received signal And a quadrant detection means for outputting a quadrant signal corresponding to a quadrant in which a received signal exists in a vector plane having a pair of Doppler signals output from the mixing means as a basic axis, and a Doppler signal having an amplitude equal to or higher than a predetermined level. When the quadrant detected by the quadrant detection means changes, a quadrant transition detection means that continuously outputs a two-level transition signal according to the direction of change until the next quadrant changes, An integration unit that integrates the output of the transfer detection unit; a threshold unit that generates a detection output when the output value of the integration unit becomes a value outside the preset upper threshold value and the lower threshold value; The Doppler system is provided with pulse generating means for inputting a pulse signal having a constant duty ratio to the integrating means so that the output of the integrating means becomes an intermediate level between the two levels of the transition signal during the period when it is not output. Object detection device. 2. When the quadrant detected by the quadrant detection unit changes to a quadrant that is not adjacent when the quadrant detected changes, the quadrant transition detection unit outputs a transition signal of a level opposite to the level when the quadrant last changed. The Doppler type object detection device according to claim 1, wherein the output is continuously performed until the quadrant changes. 3. A noise determination means for determining a Doppler signal due to noise when the phase difference between both Doppler signals is a predetermined difference or more with respect to the regular phase difference, and the noise determination means places the two Doppler signals on both sides. 2. The Doppler type object detecting device according to claim 1, wherein the pulse generating means is operated when the phase difference is not detected. 4. Noise determination means for determining that noise is received when a state in which the phase difference between both Doppler signals is within a predetermined difference with respect to the normal phase difference continues for a predetermined time or more, is provided. The Doppler type object detecting device according to claim 1, wherein the means activates the pulse generating means when detecting the noise. 5. The Doppler-type object detection device according to claim 4, further comprising noise notification means for notifying that noise has been detected based on the determination result of the noise determination means.