Application Of Analytically Solvable Chaotic Systems In Radar Ranging And Velocity Measurement

The solutions of a new class of chaotic systems that have emerged in recent years can be described by binary signals and fixed basis functions.Such analytically solvable chaotic systems?ASCS?break the view that the solution of chaotic systems cannot be described by analytical expressions.Since the ASCS can be expressed as the convolution of the binary signal and the fixed basis function,the chaotic radar based on the ASCS has the advantages of high resolution,no range ambiguity and spread spectrum characteristics.Therefore,research on ASCS has become a hot topic in the radar field.In this thesis,a method of chaos radar ranging and velocity measurement is given by using the properties of ASCS.The main work and innovations of this thesis are as follows:?1?Research on radar ranging based on ASCSA chaotic radar ranging method based on ASCS is given.Since the transmit waveform can be written as a linear convolution of the binary sequence and the basis function,and this linear representation allows the receiver to achieve target ranging by filtering the entire waveform without the need for digital sampling or signal processing.In addition,a method for reconstructing echo signals under strong noise conditions is presented.The reconstructed echo signals are correlated with the transmitted signals to achieve ranging.Compared with the existing chaotic radar ranging method,the use of ASCS has the following advantages:a)Compared to obtaining the entire continuous chaotic signal,the acquisition process of the binary sequence is easier to implement.The required signal can be directly driven by the binary sequence,and the signal is not easily distorted.Moreover,since the radar receiver only stores the binary sequence,the storage space needs to be smaller and the cost is lower.b)By directly matching and filtering the entire waveform,the discontinuity of the ranging can be avoided,and the influence of noise can be effectively reduced.c)The echo signal is based on the ASCS reconstruction,which can effectively suppress the noise interference,so that the accurate range of the radar target can still be achieved under strong noise conditions?SNR=-35dB?.?2?Research on radar target velocity measurement based on hybrid chaotic system?HCS,category of ASCS?A chaotic synchronization method is presented for the HCS,which can be used for parameter estimation,and the parameter estimation method is used to realize the velocity measurement of the radar target.By studying the relationship between the scale parameters of the chaotic system and the Doppler shift,the synchronization of the HCS is realized by the mutual coupling synchronization method.And based on the chaotic synchronization characteristics,HCS is taken as an example to give a parameter estimation method for the velocity measurement of chaotic radar.The advantage of using this method for radar target velocity measurement is that the given parameter estimation method can achieve a small estimation error,and the high-precision estimation of the scale parameter in the HCS can reach 10^-8,thereby achieving effective velocity measurement.