Research On Key Issues Of Integrated System Design

With the development of radar,communication and electronic warfare,single-platform confrontation is no longer suitable for modern warfare,and systematic combat has become a new development direction.In order to ensure the combat performance of combat equipment in a complex electromagnetic environment,the system needs to have radar,communications,and electronic jamming functions simultaneously.How to implement and evaluate these functions has become a key issue in the integrated system design.In current research,most of them focus on waveform design,and there are relatively few researches on system-level function realization and evaluation.In response to the above problems,this thesis designs the functional realization of the integrated system based on the phased array system.The system can transmit radar communication integration and communication interference integration waveforms in terms of different beams,and realize radar,communication and interference functions at the same time.The composition of the system also includes an online evaluation software part.The main work of this thesis is as follows:1.Design the composition framework of the integrated system.Firstly,the basic concept of the integrated system is introduced,and then the differences between radar,communication and jamming systems and the feasibility of the integrated system are analyzed.Finally,an integrated system is designed based on the characteristics of the phased array with multiple beams at the same time.The designed system includes three parts: radar communication integration,communication interference integration,and evaluation software.Among them,the former two adopt common waveform technology respectively,and the resource sharing of waveform,transmitter and transmitting antenna can be realized in the sub-system.The online evaluation software part uses the network to receive simulation data or integrated equipment data,and through model calculations,the evaluation results are displayed in the form of tables or figures.2.Design the integrated scheme of radar communication.Firstly,the radar detection performance of common signals is compared by using ambiguity function tool,and their differences are analyzed.Then,based on the results of ambiguity function analysis,QPSKOFDM signal is selected as the transmitting pulse according to the specific scene.In the case of instantaneous bandwidth limitation,the stepped frequency broadband synthesis algorithm is adopted to achieve high range resolution.At the same time,because OFDM signal is sensitive to frequency offset,this thesis proposes a channel estimation algorithm based on ZC pilot sequence.Through reasonable parameter design,the system still maintains good BER performance under moving conditions.On this basis,the feasibility of radar communication integrated subsystem is verified by simulation.3.Design the integrated scheme of communication interference.Communication interference integration has a wide range of application scenarios,but related research is basically blank at this stage.This thesis creatively proposes a common waveform design method based on frequency modulation slope mismatch.First,the stationary phase method is used to analyze the influence of the frequency modulation slope mismatch on the signal energy and time width after the pulse compression,which provides a standard for the parameter setting of the interference signal.Then use the communication code sequence to control the frequency modulation slope and Doppler frequency of multiple false targets to form a suppressive interference effect on the pulse compression radar;at the same time,when the communication is received and processed,the signal is processed by correlation processing and frequency detection can obtain code sequence information.The simulation results show that the signal can form a shielding effect on the target,and the system has a lower bit error rate and a higher data transmission rate.4.Design and implement the evaluation software,and use the software to test the integrated system designed in this thesis.The integrated system is in the development stage,and its performance needs to be evaluated.Based on this,this thesis uses Qt to develop an online evaluation software.The software receives the integrated system parameters through the network protocol,evaluates the system performance according to the radar,communication,reconnaissance and interference index calculation models,and finally uses the evaluation results in a curve or table form for display.In order to test the performance of the integrated system,this thesis evaluates the detection,communication and interference performance of the integrated system based on the software.Evaluation experiments show that the software has an online evaluation function.At the same time,it can be seen from the evaluation results that the integrated system designed in this thesis has good performance.