A Novel DFT-Based DOA Estimation by a Virtual Array Extension Using Simple Multiplications for FMCW Radar.

Area of Science:

• Signal Processing
• Radar Systems Engineering
• Electromagnetics

Background:

• Discrete Fourier Transform (DFT)-based Direction of Arrival (DOA) estimation is crucial for radar systems due to its low computational complexity.
• Enhancing DOA estimation resolution and reducing missing detections typically requires a higher number of channel signals.
• Physical limitations in space and cost often restrict the number of available channel signals in practical radar applications.

Purpose of the Study:

• To propose a novel DFT-based DOA estimation technique for FMCW radar.
• To overcome the limitations of physical channel constraints by virtually extending the array.
• To improve the accuracy and reliability of DOA estimation in radar systems.

Main Methods:

• A virtual array extension technique is employed, utilizing simple multiplications of existing channel signals.
• This method generates additional virtual channel signals to effectively increase the number of available signals.
• The extended set of signals is then processed using DFT for DOA estimation.

Main Results:

• The proposed scheme significantly enhances DOA estimation accuracy compared to conventional DFT-based methods.
• It effectively increases the number of channel signals without additional hardware, leading to improved performance.
• Simulation results demonstrate superior DOA estimation capabilities, and experimental validation confirms its practical effectiveness.

Conclusions:

• The novel virtual array extension method offers a cost-effective solution for improving DOA estimation in FMCW radar.
• This approach provides a practical means to achieve higher resolution and lower detection probability.
• The technique is validated through simulations and real-world experiments, confirming its utility.