Intelligent static presence detection scheme, 5.8G radar sensing technology, human presence inductive radar application

radar (RADAR) It is a kind of radio detection and distance measurement . Its main components include transmitter 、 Transmitting antenna 、 Receiver 、 receiving antenna 、 Signal processor and display ( external ). The electromagnetic energy generated by the radar transmitter is transmitted to the transmitting antenna , The transmitting antenna radiates into the atmosphere , Form the forward propagation of radar electromagnetic wave .

At run time , Radar waves are reflected when contacting objects , And obtained by the receiving antenna of the radar receiver , Form radar echo signal .

According to the principle of Doppler effect , The frequency and amplitude will change with the motion state of the impacted object . If the object touched by radar wave is fixed , Then the frequency of the reflected echo remains unchanged . If the target is close to the radar antenna , The frequency of the reflected signal is higher than that of the transmitter , contrary , When the target is far away from the antenna , The frequency of the reflected signal will be lower than that of the transmitter .

In this way, we can borrow the value of frequency change , And then processed by the signal processor , Then we can calculate the relative velocity of the target and the radar , So as to realize the positioning of the target and the determination of the shape and motion trajectory .

Compared with other sensing technologies ,5.8G Radar sensing technology has non-contact 、 Rain and fog prevention 、 Dust proof and other unique advantages , It has gradually become an important detection method in the displacement measurement of short-range targets .

Due to different signals , The measurement principle of each radar system 、 The structural group is different from Chengdu .CW The radar system is relatively simple , Only one single frequency microwave source is needed , Demodulate the target reflected signal and transmitted signal through interference , Demodulate the frequency shift and phase shift of the interference signal , You can complete the speed and displacement measurement of the target , So as to obtain high-precision measurement results .

FMCW Radar has periodic transmission frequency linear with time 、 Characteristics of continuous change , This method is based on mixing the reflected echo signal and the transmitted signal of the target , Get the signal that reflects the target distance .

Intelligent microwave radar module , Using Doppler principle , Transmit high-frequency electromagnetic waves from the antenna , Receive the processed reflected wave to judge the motion of the covered object , So as to judge the motion of the covered object , Give the corresponding electrical signal .

This is a small and complete radar system , Integrated transceiver antenna in polar small area , And it has the characteristics of low power consumption . The system can sense the motion state of objects in a closed space , Realize the detection of human motion and static state , The real realization is inductive .

Widely used in induction lighting 、 Security 、 small home appliances 、 Smart Family 、 Automatic door control switch 、 Welcome devices and other products , And the garage 、 corridor 、 Corridor 、 Courtyard 、 balcony 、 Toilets and other places that need automatic induction control .

It has a longer sensing distance and a wider angle than the infrared sensing module 、 No dead zone 、 Lens and lens aging Not affected by temperature 、 humidity 、 airflow 、 dust 、 noise 、 Light, dark and other effects , It has strong anti-interference ability and can penetrate acrylic 、 Glass and thin non-metallic materials on board MCU, Embedded multiple digital filtering algorithm , It has higher immunity .

Because the chip has been integrated 5.8G microwave circuit 、 If amplification circuit and signal processing MCU, Peripheral components , High integration and good production consistency , While ensuring the performance of the sensor, the overall size is greatly reduced .

The 5.8G Microwave radar sensor can be used to detect the presence of human body or moving target induction and other scenes , Including smart home 、 Internet of things, intelligent lighting and other fields , Especially in the home appliance and bathroom market , It can be used to realize screen wake-up control and other functions , It is widely used because of its ultra-high cost performance .

The radar sensor can be configured by a single chip microcomputer , Its sensing distance can be flexibly adjusted according to needs if the use environment is a relatively narrow space , Then the sensing distance and angle will change accordingly .

Human body can be detected within the set distance . In intelligent buildings , From the screen and display , To lighting and safety equipment , Smart home , And all devices within the scope of intelligent buildings , Can judge whether it is close enough , And trigger the operation .

Even if the user is in a static state , The intelligent presence detection scheme can also detect the inching of breathing and respond . Because of this micro motion detection function , It is suitable for interactive operation between users and devices .