FPGA based linear sweep controller implementation for FMCW radar applications

Especially for the long-distance Frequency Modulated Continuous Wave (FMCW) radar applications, the nonlinear 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 closedloop 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 the Phase Detector and a Kalman Filter as the Loop Filter. For design verification and analysis, FPGA-In-the-Loop (FIL) simulations are generated by the use of Mathworks Simulink and Xilinx System Generator.