HB100 Miniature Microwave Motion Sensor is a X-Band Bi-Static Doppler transceiver module. Its built-in Dielectric Resonator Oscillator (DRO) and a pair of Microstrip patch antenna array,
make it ideal for OEM usage in motion detection equipment.
This module is ideally suitable for false alarms reduction in intruder detectors when work together with Passive Infrared (PIR) sensor. It can also be used for auto-door opening and vehicle speed measurement.
The product is widely applied in the locations that require the auto-induction control similar to the automatic gate control switch, security system, automatic recording control system of ATM cash dispenser and automatic signal machine on the train. This is a kind of standard Doppler radar detector with 10.525GHz microwave. Comparing to other detecting methods, this one is characterized in the following advantages: 1. Not-contact detection; 2. Free from the affects of the temperature, humidity, noise, airflow, dust and light ray, and suitable with the extreme environments; 3. Strong ability of radio-frequency interference resistance; 4. Output power is only 5mW, no harming to the human body; 5. Long range: detection coverage is over 20 meters.
Introduction to Doppler principle: Doppler theory is based on the time. When the radio wave comes up against the object under way, it will be reflected and the frequency of the reflected wave will be changed by the moving state of the object. If the position of such object is fixed, the frequency of the reflected wave will be equal to the one of the transmitted wave. If the object moves along the emissive direction, the reflected wave will be compressed, namely the frequency of the reflected wave will be strengthened; Contrarily, if the object moves against the emissive direction, the frequency of the reflected wave will be reduced and that is the Doppler effect. Such phenomenon is normal in the daily life. For example, as a whistling police wagon fast passes by your side, you will hear the changes of the frequency of the sound: when the police wagon approaches to you with the high speed (comparing to the fixed sound source), the transmission time of the sound is shortened and the frequency is increased. While the police wagon is far from you, the transmission time of the sound is lengthened and the frequency is decreased.
Application Example I: Automatic Door Control and Automatic Recording Control of ATM Cash Dispenser
The product is widely applied in the locations that require the auto-induction control similar to the automatic gate control switch, security system, automatic recording control system of ATM cash dispenser and automatic signal machine on the train. This is a kind of standard Doppler radar detector with 10.525GHz microwave. Comparing to other detecting methods, this one is characterized in the following advantages: 1. Not-contact detection; 2. Free from the affects of the temperature, humidity, noise, airflow, dust and light ray, and suitable with the extreme environments; 3. Strong ability of radio-frequency interference resistance; 4. Output power is only 5mW, no harming to the human body; 5. Long range: detection coverage is over 20 meters.
Introduction to Doppler principle: Doppler theory is based on the time. When the radio wave comes up against the object under way, it will be reflected and the frequency of the reflected wave will be changed by the moving state of the object. If the position of such object is fixed, the frequency of the reflected wave will be equal to the one of the transmitted wave. If the object moves along the emissive direction, the reflected wave will be compressed, namely the frequency of the reflected wave will be strengthened; Contrarily, if the object moves against the emissive direction, the frequency of the reflected wave will be reduced and that is the Doppler effect. Such phenomenon is normal in the daily life. For example, as a whistling police wagon fast passes by your side, you will hear the changes of the frequency of the sound: when the police wagon approaches to you with the high speed (comparing to the fixed sound source), the transmission time of the sound is shortened and the frequency is increased. While the police wagon is far from you, the transmission time of the sound is lengthened and the frequency is decreased.
Application Example I: Automatic Door Control and Automatic Recording Control of ATM Cash Dispenser
The operating distance of this circuit is 4 to 15 meters, with continual adjustment. Compared to the pyroelectric infrared detector, it is characterized in the advantages of anti-highlight interference, far range of detector and free from the affects of the temperature and humidity.
Circuitry introduction: in the figure, U1 is the module of the microwave inductive probe, providing the module with 2 kHz pulse electric source by K202, K203, R202 and R219 (the circuits that can produce the frequency of 2 kHz with the high level width of 20uS are abundant, as using the reverser CD4069 and Im555). During the operation of U1, K201 plays the role of the conduction, taking the gating output of the low frequency signal from the moving object transmitted by U1; C202 is the sampling hold circuit to guarantee the continuance and integrity of the signal. The two poles of low-pass amplifying circuit made from LM358 will amplify the output from U1 and transmit at foot 1 of LM358.The variable resistor R213 is used to adjust the gains of the first amplifier and when we adjust the size of R213, the range of detector will be adjusted.
Application Example II: Switch Circuit of the Automatic Signal Machine on the Train
Operating distance is 1 to 9 meters with continual adjustment. This circuit has stronger anti-interference ability and larger range of adjustment, which can be applied in the wild and the locations with the severe conditions.
Principle introduction: The above figure is the complete application circuit. U3D (LM339) and the surrounding relative elements form the oscillator with low duty ratio of 2 kHz. P1 and P2 supply the pulsating electric source and gating.E9 adopts the hold capacitance and the low frequency signal from the moving object is amplified by the low-pass amplifying circuit which is made up of LM324 A, B and the surrounding elements and then it will come to the comparator formed with LM324 C and the relative elements around. The low-pass filter network consisted of C9-C12 and R32-R35 will filter the interfering signal with the line frequency. The time delay circuit made up of U3A can guarantee the circuit have the certain time for the firm output when observe the movement of the object. The gains of the first amplifying circuit which is consisted of U1A and the relative elements is: A1A≈R30/ R31 = 375 / 473 = 78.7; the second amplifier is made up of U1B and the relative circuit and the amplifying gains A1B≈R36/(R35+R34)=475/943=50; the gains of the amplifying gains of the two poles A=78.7×50＝3935, namely 36db. The voltage comparator, which is made up of U1C, R39, R40, P2 and E12, translates the former magnifying signal into the pulse signal and then it is transmitted by the time delay circuit consisted of U3A and the relative elements. When we adjust the size of P2, the range of detector will be changed and the size change of R41, E13 and R42 will adjust the length of the output time.
Application Example III: Tri Technology Probe
Principle introduction: Tri technology means the integrated probing technique of infrared dominant, microwave assistant and SCM intellectual treatment (PIR/MW/AI). When the passive infrared observes the object, it will start up the microwave detecting circuit. Only both signals are effective and accordance with the output condition of the alarming by the intellectual treatment of SCM, SCM will transmit the alerting signal.
Circuit analysis: The passive infrared (PIR) signal in this circuit is transmitted to the input port foot 17 and 18 on the comparator of SCM by the filtration and the comparator directly converts the signal induced by the infrared probe into the pulse signal. After the treatment of MPU PIC16C622A, the digital signal can be dealt with the software for the identification of the outcome and income and the filtration of the interference.RB1 exports the pulse of 2 kHz with the duty ratio of 5% (the width is 20uS) and the drive P2 provides the microwave detector with the pulse power supply. The low-frequency output of the microwave detector is exported through P1 gating to C101, which adopts the hold capacitance. The low frequency signal of the moving object is amplified by the programmable operational amplifier, which is made up of U1A and the relative elements, and it will then take the level conversion by the comparator made up of U1B. The pulse signal, after the conversion, will be exported to MPU from foot RB3 on PIC16C622.
When the infrared observes the object, RB1 will transmit the high level, the triode K3 begin the conduction, the gains of the programmable amplifier made up of U1A be increased from 100 times to about 10000 times, the microwave detector circuit go into operation and MPU begin to detect the moving signal of the object. By analyzing PIR signal, MPU can estimate the in and out status of the infrared source and then it can exclude the interference of the hot air and the non-thermal source moving objects (as flying curtain, spinning electric fan and other). Meanwhile, along with the integration of the signal of the microwave detector, it can exclude the interference of multi-thermal sources.
The rational MPU mathematical model and scientific compilation software can recognize the pet with the weight lower than 20kg.It can basically eliminate the misstatement resulted from the pets.
When change the size of P1 in this circuit, it can change the gains of the amplifying circuit and then adjust the range of detector of the microwave circuit.
