The Research Of Broadband Linear Sweeping Source Based On AD9858

DDS is of fast frequency switching speed,high frequency resolution,the function to switch frequencies while maintaining constant phase.It is very convenient to achieve many kinds of modulations and to be controlled by micro-processor.The DDS technique has gained its rapid development in recent years,which will be applied more and more extensively in such fields as radar,communications, electronic warfare and electronic measurement instruments.This paper introduced the concept of the direct digital frequency synthesis technology(DDS).This paper given out the design of making use of the AD9858 to realize the 100—260MHz wide band frequency sweeping source program,also has given the structure of the hardware circuit and the software debugger result.Using the PLL chip ADF4360-2 to achieve the AD9858's needed 1GHz reference clock design and Designing the TMS320F2812,AD9858 and the ADF4360-2 hardware interface circuit,Carried out the software programming and debugging For suppressing the DDS spur,the paper has introduced the design and debugging of multi-channel filter banks it also has analyzed the group delay of each filter through the simulation.The test results prove that the design is reasonable.