Research On Peak-to-average Power Ratio And Constant Power Synthesis Of Multi Signal

With the gradual development of modern electronic warfare technology,the electromagnetic environment which both sides of the battle fight at is becoming more and more complex.For the case that there are multiple radar threat sources,multiple unrecognized bait radiation sources,and multiple false threat signals at the same time,jamming system needs to reasonably schedule,allocate and manage various jamming resources to make effective interference.When jamming resources are limited,jamming resources need to have the ability to simultaneously interfere with multiple threat signals.As a result,the radiated output signal may be a synthetic jamming signal.To meet this demand of jammer,digital jamming synthesis(DJS)technology has gradually developed and matured.However,the jamming system fully using DJS based on a linear synthesis technique has high peak-to-average ratio(PAPR).Also,the number of synthetic signals is more,the PAPR becomes higher.Therefor,the effective power of jamming to the enemy electronic information system will be severely reduced.To solve this problem,theoretical analysis and simulation techniques are used to study the following three parts:1.This thesis introduces the basic composition,performance indicators and typical jamming patterns of DJS.After explaining the principle of radio frequency noise interference,the process of generating it in DJS system is implemented through simulation.This thesis also points out the problem that the PAPR of the DJS system is very high.2.This thesis describes the knowledge about the PAPR in DJS jamming systems,analyzes in detail the effect that signal with high PAPR has on DJS jamming system,and briefly introduces the implementation,advantages and disadvantages of the methods commonly used to reduce the PAPR.3.This thesis does the research on reducing the PAPR of synthetic signal through hard-limiting and soft-limiting methods,introduces in detailed basic principle and implementation of the two methods,and analyzes the problem of signal distortion and spectrum broadening caused by the limiting method.The different effects that two methods have on spectrum broadening of synthesized signal is researched by simulation.Through the study of the three parts above and based on detailed analysis of the working principle of the DJS jamming system,the thesis gives the conclusion that the problem of spectrum broadening caused by limiting methods needs to be solved when PAPR is reduced through using limiting methods.