Radar Waveform Generator based on DDS

Abstract: A radar waveform generator is implemented and it is designed by using directly digital modulation method based on DDS. It is able to generate arbitrary signals whose frequency amplitude and phases are controlled by the description words which will be given from external computer. Accurate waveforms are generated. By using Direct digital synthesis technique we can generate waveforms digitally . DDS technique is widely applicable and simple. Direct Digital Synthesizer (DDS) is a frequency synthesizer and it can generate arbitrary waveforms by using single, fixed- frequency reference clock. Some of the DDS Applications are: function generators, modulators. For implementing radar waveform generator along with DDS we need FPGA and PIC microcontroller. To generate the waveform using DDS we need to store the hexadecimal data into the internal registers of DDS chip along with that we need some control signals which will be generated using FPGA . First in PC we need to enter the information of the signal to be generated for that we need design a Graphical User Interface (GUI).In GUI we will enter the amplitude, frequency and phase of the waveform to be generated and then it has to covert that particular data into hexadecimal data based on the formulas mentioned in AD9910 datasheet, then it has to send that data to microcontroller through serial port. Now, microcontroller will receive that data from PC and then it has to send that data to the FPGA. FPGA will receive that data, along with that it has to generate some control signals and clock signals based on the control signals, received data has to be send to the internal registers of DDS chip.

Keywords: Direct Digital Synthesizer(DDS) ,Field Programmable Gate Array(FPGA),Graphical User Interface(GUI), microcontroller