Research On Radar Echo Characteirstics Of Insect Movement Based On Micro-doppler Effect

As the bionic study of insect movement mechanism is expected to provide new ideas andtheoretical directions for the design of micro bio-robot, the measurement of insect kinematicsparameter in natural condition has a magnificent significance for this study. In the study of themeasurement of insect kinematics parameter, the difference between insect’s livingsurroundings and the detect environment of laboratory building has became the bottleneck forthe further development, so a new way to acquire insect kinetic characteristics is thefundamental solution. This paper proposes insect kinetic characteristics capturing systembased on micro Doppler principle, which can not only detects insect kinetic characteristics,but also depicts the motor behaviors of all parts of insect’s body in detail.First, this paper elaborates the existing problems in the information acquisition of insectkinematics from the point of its acquiring method. Then, in accordance with the application ofradar, as well as the development situation of micro Doppler Radar in space, ground,organism’s motion feature and human’s vital signs, this paper proposes the relevant issues ofacquiring insect kinetic characteristic in echoes of Doppler Radar. What’s more, it also coversthe objective model of micro Doppler echo equation, time-frequency analysis and extractionmethod of characteristics as well as the modulating actions of radar echo for the linear insectbody movement. Finally, the exploratory study on insect’s micro Doppler feature analysis andthe recognition of motor pattern.In allusion to the objective model of micro Doppler echo equation and time-frequencyanalysis and extraction method of characteristics, first, we can take advantage of quadraturedetector and band-pass filter to acquire the micro Doppler signals based on electromagneticwave echo theory and scattering properties of the targets. Then, by virtue of the general typeof micro Doppler echo for the point target, we can deduce its analytical expression created byblocking vibration and analyze the waveform through the first order Bessel function. Takingadvantage of time-frequency analysis methods, such as STFT、WVD、SPWVD、RSPWVD,many point target echo simulations can be analyzed. Reflect the superiority of choosingRSPWV analytical method through the comparison of time-frequency spectrum. Finally,elaborate the characteristics of time-frequency spectrum, compare its characteristics throughfirst order time-conditional moment, peak detection and Image baseline method of Lablacian,and verify the merits extracted from the echoing spectrogram including noise based on Image baseline method of Lablacian.As for the modulating action of electromagnetic wave for the linear insect bodymovement, first, on the basis of the “hinge” construction of snake-shaped robot and workingmode of radar utilized by the system, we propose structural model that are suitable for thestudy of linear insect’s radar characteristics. Taking Tenebrio molitor as an example, linearinsect’s body can be divided into head, abdomen and tail. Then, through analyzing the motionform of different parts of Tenebrio molitor’s body, as well as its radar echo analyticalexpression deduced from the point target radar echo equation, we can acquire micro Dopplercharacteristics in the radar echoes of different parts of Tenebrio molitor and do the study on itstime-frequency component by utilizing time-frequency analytical tools and feature extractionmethod.To support the research work in this paper of the Doppler echo simulation of Tenebriomolitor motion, the micro Doppler radar detection system is designed and completed ofmoving targets operating at K band. Firstly, it conducts the demand analysis of the microDoppler radar system of moving targets, and puts forward the composition and structure ofradar system. Then it completes the hardware design of radar detection system, focusing onthe design of micro Doppler radar radio frequency front end (the simulation and design ofmicrostrip antenna, system receipt and gain control of transmitting terminal, and extractionand further processing of Doppler echo signal) to set forth here. And then after the access tothe radar Doppler echo signal, it realizes the real-time acquisition, storage, and datacommunication of host computers of echo signal based on the central processing unit ofSTM32. Finally, it realizes time-frequency analysis of the echo signal by the use of thetime-frequency analysis toolbox of MATLAB in host computers.Aiming at the micro Doppler feature analysis and pattern recognition problems of theTenebrio molitor, this paper, by use of structures of the micro Doppler radar detectionplatform for the moving target, collects the micro Doppler echo signal of the Tenebrio molitorunder different forms of motion morphology. In order to achieve a good electromagneticshielding effect, this paper uses the anechoic chamber constructed by absorbing materials toshield the echo signal. Then it detects by advantage of the Doppler radar detection system themotion forms of the head swinging, tail swinging and crawling movement of single Tenebriomolitor and the Doppler echo of the movement of two or many Tenebrio molitors. And itcompletes the time-frequency analysis and feature extraction of echo signal, in which gets theecho characteristics of each movement parts of the Tenebrio molitor body, to support theresearch of this task. Finally, it will analyze some problems exposed in the detection process of the detection platform with the radar, and put forward improving plan for the next step.Finally, it will be the summary of the main research work, and analyze the developmenttrend of the research content and application prospect, thereby it will point out the problemsthat need further study and solve.The main work of this paper is to propose a new method of the information acquisitionmodel of insect kinematics, and to discuss the feasibility of the information acquisition ofinsect kinematics by using the method. Because this method involves a relatively wide field,and are all the frontier technologies of the high-frequency electromagnetic wave, the work ofthis paper is just exploratory, to a certain extent, which can only be regarded as the initialstage. In the future, for different types of insect kinematics information acquisition system,there will be many problems to be studied and further resolved.