L frequency band small step frequency synthesizer

The utility model discloses an L frequency range small stepping frequency synthesizer, which relates to a frequency synthesizer device of a remote measuring upstream channel in the aerospace observe and control field. The L frequency range small stepping frequency synthesizer is composed of a DDS unit module, a DDS frequency conversion unit module, a phase-locked loop module, a frequency mixing unit module, a reference source splitter, a monitoring circuit, a LCD, a key board, a power-supply module and the like. The frequency synthesis with compromised L frequency range upper wideband and high frequency resolving capability is realized by respectively setting frequency values of the DDS unit module and the phase-locked loop module by the monitoring circuit, and processing two times frequency conversions by the build-in DDS frequency conversion unit module and the frequency mixing unit module. The utility model has the characteristics of high frequency resolving capability, low phase noise, high spectrum purit