High density FPGA based waveform generation for radars

Various modulation techniques are usually utilized to enhance the radar performance, or to add more capabilities to the radar that otherwise would not have been possible. Digital generation methods of frequency modulated continuous wave signals include direct waveform synthesis and frequency synthesis. The implementation of waveform generation and upconversion method are described in this paper with a simplified digital implementation technique using FPGAs (Field Programmable Gate Array). The design follows a systematic approach following steps of timing generation from external encoder, baseband modulated waveform generation, upconversion of the waveform to intermediate frequency, filtering and finally frequency synthesis using external DDS (Direct Digital Synthesizer). The design is also capable of generating BITE waveform for test checking in the system. Our design is capable of generation of waveform for stationary as well as non-stationary radars. For non-stationary radars, the waveform is so generated that the doppler effect due to the movement of the radar is compensated. The paper explains more on this. This work mainly focuses on the fact that the total design has been implemented on a single FPGA and the implementation solution utilizes the efficient FPGA resources so as to meet the timings in crucial applications. Moreover, the paper enhances the features of the design with simulation and real time results used to validate the design.