【摘 要】
：
This paper introduces a new approach for the determination of the source region of beat wave (BW) modulation.This type of modulation is achieved by transmitting high-frequency (HF) continuous waves with a frequency difference f,where f is the frequency of
【机 构】
：
College of Meteorology and Oceanography,National University of Defense Technology,Changsha 410073,Ch
论文部分内容阅读
This paper introduces a new approach for the determination of the source region of beat wave (BW) modulation.This type of modulation is achieved by transmitting high-frequency (HF) continuous waves with a frequency difference f,where f is the frequency of modulated ELF/VLF (extremely low frequency/very low frequency) waves from two sub-arrays of a high power HF transmitter.Despite the advantages of BW modulation in terms of generating more stable ELF/VLF signal and high modulation efficiency,there exists a controversy on the physical mechanism of BW and its source region.In this paper,the two controversial theories,i.e.,BW based on D-E region thermal nonlinearity and BW based on F region ponderomotive nonlinearity are examined for cases where each of these two theories exists exclusively or both of them exist simultaneously.According to the analysis and simulation results presented in this paper,it is found that the generated VLF signal amplitude exhibits significant variation as a function of HF frequency in different source regions.Therefore,this characteristic can be utilized as a potential new approach to determine the physical mechanism and source location of BW.
其他文献
We present a new method for calculation of quasi-potential,which is a key concept in the large deviation theory.This method adopts the “ordered” idea in the ordered upwind algorithm and different from the finite difference upwind scheme,the first-order li
This paper presents a new hyperbolic-type memristor model,whose frequency-dependent pinched hysteresis loops and equivalent circuit are tested by numerical simulations and analog integrated operational amplifier circuits.Based on the hyperbolic-type memri
Based on the fact that the electronic throttle angle effect performs well in the traditional car following model,this paper attempts to introduce the electronic throttle angle into the smart driver model (SDM) as an acceleration feedback control term,and
With the rapid development of communication technology,optical fiber communication has become a key research area in communications.When there are two signals in the optical fiber,the transmission of them can be abstracted as a high-order coupled nonlinea
A new design of staggered array semi-packed micro gas chromatographic column was presented based on the micro electromechanical system (MEMS) technology.It was a sensor for gas sample analysis.The internal velocity fields of ten types of semi-packed micro
Linear and nonlinear dust acoustic (DA) waves have been investigated in an opposite polarity dusty plasma comprising negatively and positively charged dust grains,Maxwellian electrons and ions,including the generalized polarization force effect.The proper
A new type of x-ray lens composed of multi-square polycapillary slices (ASPXRL) used in focusing parallel x-ray beam was presented in this paper.Compared with conventional x-ray polycapillary lens,ASPXRL can provide smaller and brighter focus.The effects
A scheme for instantaneous frequency measurement (IFM) using two parallel I/Q modulators based on optical power monitoring is proposed.The amplitude comparison function (ACF) can be constructed to establish the relationship between the frequency of radio
We investigate the dynamic event-triggered state estimation for uncertain complex networks with hybrid delays suf-feting from both deception attacks and denial-of-service attacks.Firstly,the effects of time-varying delays and finite-distributed delays are
Systematic calculations and assessments are performed for the magnetic dipole (M1) transition energies and rates between the 2F50/2,7/2 levels in the ground configuration 4d104f along the Ag-like isoelectronic sequence with 62 ≤ Z ≤94 based on the second-