Sweep generation for FMCW radar applications

Especially for the long distance Frequency Modulated Continuous Wave(FMCW) radar applications, the non linear frequency sweep due to the Voltage Controlled Oscillators (VCO) results in range resolution degradation. Open loop control solutions like Voltage Pre-Distortion method are not adequate for the applications like FMCW Radar Altimeter because of the noisy and non-stationary structure of the system due to the environmental conditions. In these situations closed loop control systems like Phase Lock Loop (PLL) provide more sufficient results. In this research; a PLL structure is implemented on an Field Programmable Gate Array (FPGA) by a Direct Digital Synthesizer(DDS) as the Reference Signal Generator, an improved Phase Frequency Detector as Phase Detector and Kalman Filter as the Loop Filter. For design verification and analysis, FPGA –In the Loop (FIL) simulations are generated by the use of Math works Simulink.