Robust free-space optical frequency transfer in time-varying link distances conditions

Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects. Here, we demonstrate robust optical frequency transmission under the condition of variable link distance. This variable link is accomplished by the relative motion of a single telescope fixed on the experimental platform to a corner-cube reflector(CCR) installed on a sliding guide. Two acousto–optic modulators with different frequencies are used to separat...     

对一道试题的研讨

<正>最近,广州市几个区联合举行了调研考试(即期中区统考),我们也参加了这次考试,有一道数列解答题的第三问,我们区没有一人做对(听教师说).题目如下:在数列{an}中,a1=1,a2=3,an+2=3an+1-kan(k≠0)对任意n∈N*成立,令bn=an+1-an,且{bn}是等比数列.(1)求实数k的值;(2)求数列{an}的通项公式;     

对一道试题的研讨

最近,广州市几个区联合举行了调研考试（即期中区统考）,我们也参加了这次考试,有一道数列解答题的第三问,我们区没有一人做对（听教师说）．题目如下：