【摘 要】
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Frequency domain anti-jamming (FDAJ) has been widely adopted by most of military satellite navigation receivers.It is simple in theory and easy for realization.It can effectively suppress single tone
【机 构】
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National university of defence technology, Changsha, China
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Frequency domain anti-jamming (FDAJ) has been widely adopted by most of military satellite navigation receivers.It is simple in theory and easy for realization.It can effectively suppress single tone interference,sweep interference and narrow band interference with Gaussian distribution.However,FDAJ will result in distortion of navigation signal,while suppressing interference.Previous works about effects of FDAJ on navigation signal havent taken interference spectrum leakage induced by time window shaping.It results in effects of FDAJ on navigation signal has no relationship with interference power,which violates the practical.Therefore,take narrow band interference with Gaussian distribution as an example.Firstly,its spectrum leakage induced by time window shaping is analyzed.Then,extra FDAJ loss induced by interference leakage is analyzed.Finally,FDAJ theoretical model of effects on effective carrier-to-noise ratio (CN0) and pseudo code tracking variance is derived,taking interference spectrum leakage.Numerical computation show that,effective CN0 and code tracking variance increase with jam-to-noise ratio (JNR),when FDAJ suppresses narrow band interference shaped by time window,different from ideal one (without spectrum leakage).When adopting different time window,rate of receiver performance deterioration with JNR increase caused by FDAJ is different.When adopting Hamming or Hanning window,the rate is far lower than that of rectangular window.
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