A method of improving the accuracy of laser pulse range finding from ±10 m to ±1 m inexpensively by means of time scale up is described. Time scale up can stretch the entire flight time by a factor of 1 00...A method of improving the accuracy of laser pulse range finding from ±10 m to ±1 m inexpensively by means of time scale up is described. Time scale up can stretch the entire flight time by a factor of 1 000 and then the stretched result is counted to calculate the distance. The use of this technique decreases the resolution of counting from nanosecond to microsecond, therefore a separate counting oscillator followed by an interpolation operation is unnecessary. This technique can improve the accuracy of laser pulse range finding inexpensively and effectively.展开更多
As microsatellite technology develops,precise inter-satellite measurement shows its significance in distributed satellite systems.In this Letter,a novel technique is proposed for measuring the inter-satellite distance...As microsatellite technology develops,precise inter-satellite measurement shows its significance in distributed satellite systems.In this Letter,a novel technique is proposed for measuring the inter-satellite distance,which adopts optoelectronic resonance and has a function of self-referencing.Resonance cavities have a high spectral purity and a high oscillation frequency.By utilizing the accumulative amplification principle to convert the measurement of distance to that of the frequency,high accuracy is achieved.In the experiment,this measuring scheme has a large measuring range between 1 and 6 km（can be potentially larger）,and the accuracy is better than 1.5 urn.The relative accuracy reaches the level of 10^-10.展开更多
文摘A method of improving the accuracy of laser pulse range finding from ±10 m to ±1 m inexpensively by means of time scale up is described. Time scale up can stretch the entire flight time by a factor of 1 000 and then the stretched result is counted to calculate the distance. The use of this technique decreases the resolution of counting from nanosecond to microsecond, therefore a separate counting oscillator followed by an interpolation operation is unnecessary. This technique can improve the accuracy of laser pulse range finding inexpensively and effectively.
基金supported in part by the Chinese National Natural Science Foundation(Nos.61427817 and61405142)the Independent Innovation Fund of Tianjin University(No.1601)
文摘As microsatellite technology develops,precise inter-satellite measurement shows its significance in distributed satellite systems.In this Letter,a novel technique is proposed for measuring the inter-satellite distance,which adopts optoelectronic resonance and has a function of self-referencing.Resonance cavities have a high spectral purity and a high oscillation frequency.By utilizing the accumulative amplification principle to convert the measurement of distance to that of the frequency,high accuracy is achieved.In the experiment,this measuring scheme has a large measuring range between 1 and 6 km（can be potentially larger）,and the accuracy is better than 1.5 urn.The relative accuracy reaches the level of 10^-10.
文摘全球导航卫星系统(Global Navigation Satellite System,GNSS)是目前应用最广泛的导航系统之一,但导航卫星信号到达地面时比较微弱,容易受到干扰,且无法在室内和城市峡谷环境中使用。近年来,移动通信技术发展迅速,具有基站布站密度高、信号信噪比强的特点,常被作为机会信号(Signal of Opportunity,SOP)定位导航系统进行研究。5G移动通信采用极简化设计,用于信道质量估计的参考信号不能随时获取,限制了利用上述信号实现SOP定位可能性。针对以上问题,结合5G移动通信中的波束成形技术,充分利用5G新引入的同步信号块(Synchronization Signal Block,SSB)中的解调参考信号(Demodulation Reference Signal,DMRS),提出了基于5G参考信号的测距测向方法,实现了多径误差补偿的测距技术和基于信噪比拟合的测向技术。实验表明,测距均方根误差(Root Mean Square Error,RMSE)为21.3 m,比不使用DRMS时的精度提高了46.1%;测向RMSE为7.9°,使得未来利用5G移动通信参考信号构建SOP定位导航系统成为可能。
