CAJ | 학술논문

为实现X射线脉冲星导航系统在地面的演示验证,提出并设计了一种高精度X射线脉冲星仿真源.该仿真源由模拟调制信号发生器和栅控X射线球管组成.模拟调制信号发生器根据脉冲星标准脉冲轮廓数据和栅控球管特性曲线,利用直接数字频率合成技术产生模拟调制信号,加载在X射线球管控制栅极,从而控制轰击阳极靶的高速电子数目来实现X射线的调制,产生与脉冲星标准脉冲轮廓高吻合度的X射线光子统计分布.在X射线脉冲星地面仿真系统中对Crab脉冲星仿真源的性能进行测试,测试结果为:采集脉冲轮廓与标准脉冲轮廓时域相关度和频率相关度分别达到0.9774和0.9853,辐射流量为1.90 ph·cm?2·s?1,脉冲辐射流量与总辐射流量之比为76.15%,脉冲半宽度为1.879 ms.结果表明:该仿真源具有符合度高,成本低,操作简单灵活,对X射线脉冲星导航关键技术的攻关具有重要的意义.
위실현X사선맥충성도항계통재지면적연시험증,제출병설계료일충고정도X사선맥충성방진원.해방진원유모의조제신호발생기화책공X사선구관조성.모의조제신호발생기근거맥충성표준맥충륜곽수거화책공구관특성곡선,이용직접수자빈솔합성기술산생모의조제신호,가재재X사선구관공제책겁,종이공제굉격양겁파적고속전자수목래실현X사선적조제,산생여맥충성표준맥충륜곽고문합도적X사선광자통계분포.재X사선맥충성지면방진계통중대Crab맥충성방진원적성능진행측시,측시결과위:채집맥충륜곽여표준맥충륜곽시역상관도화빈솔상관도분별체도0.9774화0.9853,복사류량위1.90 ph·cm?2·s?1,맥충복사류량여총복사류량지비위76.15%,맥충반관도위1.879 ms.결과표명:해방진원구유부합도고,성본저,조작간단령활,대X사선맥충성도항관건기술적공관구유중요적의의.
In this paper a high resolution X-ray simulation source is proposed and designed to verify the navigation based on X-ray pulsar in the simulation experience system. The simulation source consists of an arbitrary signal generator and a grid controlled X-ray tube. According to the grid tube’s characteristic curve, the data of the pulsar standard pulse template are converted. Then using the method of direct digital frequency synthesis, the converted data are synthesized to waveforms, called the analog modulated grid voltage. In the grid controlled X-ray tube, the grid voltage changes the number of electrons hitting on the target and controls the X-ray intensity. With an analog modulated pulse profile applied on the tube grid electrode, the tube will emit X-rays which will match photons’ statistical distribution and simulate the X-ray pulsar profile extremely well. The properties of Crab pulsar simulation source are tested in X-ray pulsar navigation simulation experience system. The results of the test are as follows: Comparing the tested pulse profile with the standard pulsar profile, we have time correlation coefficient is 0.9774, and frequency correlation coefficient is 0.9853. The X-ray photon flux is 1.90 ph·cm?2·s?1, the pulsed fraction is 76.15%, and the half-width half maximum is 1.879 ms. These results show that the X-ray simulation source has several merits, such as:strong ability to simulate the X-ray, low cost and simple operation. So it is an important means for the improvement of X-ray pulsar navigation.