In this paper

the millimeter wave wide-bandwidth ultra-linear sweeping technique is studied

the new theory consisting of phase-locked technique and delay-line to improve the linearity is presented

the design principle of phase-locked sweeping loop（PLSL） is deduced

and the non-dispersion delay line

digital phase-locked loop

monolithic microwave components and high-performance millimeter-wave components are used.In structure

the high-density assembly technique and SMT are utilized.The sweeping source’s main performance indexes are as follows:Bandwidth is 500MHz

linearity is superior to 0.01 %.