The Theory of DDS and Its Implement
|School||Shanghai Jiaotong University|
|Keywords||Direct Digital Synthesize (DDS) FPGA CORDIC|
Direct Digital frequency Synthesis (DDS) was advanced rapidly in early 1970s and has been developing owing to its entirely digital structure. The appearance of Field Programmable Gates Array has changed the design method of digital electronical system and provided a new design model. this paper primarily introducing the basic principle extensive and applied foreground of DDS , emphasizing the example of FPGA realizing DDS on SIN signal synthesize to expound this technique in engineering practice with the key technique。In this example, we take the real time way using CORDIC(Coordinate Rotation Digital Computer) in calculate the sine the SIN that value conventionally was got with seek the form( LOOK- UP TAB) method, a much better resolving power on signal’s frequency, so greatly expand the application fields of DSS. Through verification by simulation and experiment, the proof should the processing method is viable with valid. Moreover, we use the principle of flow operation to carry out many channels wave, and those waves can control, such design makes reduce the hardware, contracting the physical volume of the product.The paper is divided into four parts. In first part we introduce the concept of Direct Digital Synthesize (DDS), describe the current level of this technique in the domestic and international. Chapter 2 and chapter 3 as second part, we introduce the theory of Direct Digital Synthesize (DDS) and CORDIC(Coordinate Rotation Digital Computer). Chapter 4 and chapter 5 as third part, we introduce the process and the result of the example. Chapter 6 as the four-part, describe the research result and innovation.