<FONT face=Verdana>A novel design scheme of phaselocked system of hydrogen maser frequency standard is proposed based on equivalent phase comparison frequency.Using the regularity of the variation of phase difference between frequency signals

linear phase comparison is possible without the same frequency between them

namely different frequency phase comparison.If different frequency phase comparison is used in PLL of the hydrogen maser frequency standard

through suitable choice of the equivalent phase comparison between reference signal and locked signal

we can directly compared phase between different frequency signals and obtain very high phaselocked precision.Experimental results show that the design scheme is advanced and scientific.Its phaselocked precision can reach the order of magnitude of 10-12/s.Compared to traditional phaselocked system of hydrogen maser frequency standard

the system is high in phaselocked precision

simple in circuit structure

small in additional noise

and can be direct phase comparison between different frequency signals.Thus it is widely used in navigation positioning

space technology

communication

metrology

precise timefrequency measurement and control and so on.