【摘 要】
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Passive hydrogen maser(PHM)has the advantages of high frequency stability and low frequency drift.It has been widely used in the navigation system and frequency calibration.Atomic transition signal am
【机 构】
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Shanghai Astronomical Observatory,Chinese Academy of Sciences Shanghai,People's Republic of China,2
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Passive hydrogen maser(PHM)has the advantages of high frequency stability and low frequency drift.It has been widely used in the navigation system and frequency calibration.Atomic transition signal amplitude of PHM directly determines the system signal to noise ratio,and thus affect system performance,which makes it one of the most important parameters of PHM.
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