Research On Multitasking-oriented Integrated Waveforms Of Frequency Diverse Array Radar And Communication

Under the condition of modern high-tech war,it is difficult to deal with the enemy's comprehensive high-tech electronic weapons and achieve reliable communication,detection and suppression by any single electronic equipment or simple superposition of multiple electronic equipment.Radar and communication are two important parts of the combat platform,and it is of great significance to realize the integration of them.Frequency Diverse Array(FDA)is a special form of array evolved from phased array.At the same time,it has the advantages of phased array and its own characteristics.FDA's beam pattern has dual dependence and coupling in angle and distance.The transmitted beam no longer depends on the phase shifter in space scanning,and the freedom of beam energy accumulation is improved.In this paper,the advantages and characteristics of FDA are applied to the radar communication integration system.Therefore in order to overcome the difficulty of separating the integrated signal at the receiving end and to solve the problem of angle-distance coupling in the beam pattern.In this paper,FDA and orthogonal frequency division multiplexing(OFDM)technology is applied to the waveform design of radar and communication integrated signal,and the main innovative contents are as follows:1.Aiming at the integrated signal design problem of OFDM system and frequency diversity array radar under the condition of single pulse,advance the design that each array element carries the same OFDM-FDA radar communication integrated waveforms,which loads the OFDM symbol directly on the FDA radar array element in the form of longitudinal,and each array element transmits the multicarrier with the same communication information.The scheme is easy to implement and has high carrier gain,but low band utilization.2.Aiming at the defect of low frequency band utilization of the first waveform design scheme,a waveform design method of OFDM-FDA radar and communication integration based on random array element is proposed.The subcarriers of OFDM symbols are randomly distributed on the array elements to generate a random OFDM-FDA radar and communication integrated signal.And the frequency band utilization is effectively improved.The signal model,beam pattern function,radar target positioning effect and other aspects are analyzed in detail.Two positioning algorithms are used to simulate the effects of single target positioning and multi-target positioning.And analysis is made on the problems of the waveforms.3.In consideration of the low data transmission rate of the above two integrated waveform design schemes,an OFDM-FDA radar and communication integrated waveform based on random frequency interval is designed.Each radar array carries a complete OFDM symbol with different information,and random frequency intervals are added between the array elements to determine different signal frequencies,which not only solves the problem of separation and uncoupling of radar communication integrated signal at the receiving end,but also improves the utilization rate of band and information transmission rate of the radar communication integrated system.This paper analyzes the basic characteristics of the waveform from theoretical analysis and simulation experiment,studies the performance of radar system and communication system respectively,and applies the waveform design to the bistatic radar mode to ensure the accurate and timely transmission of radar signal and communication signal to the receiver.