DAB Signal Preprocessing for Passive Coherent Location

Area of Science:

• Radar Systems
• Signal Processing
• Electromagnetics

Background:

• Digital Audio Broadcast (DAB) transmitters offer a viable illumination source for Passive Coherent Location (PCL) systems.
• Integrating DAB signals in PCL can introduce periodic artifacts in range/Doppler plots due to the signal's inherent time structure, hindering performance.

Purpose of the Study:

• To propose and evaluate signal preprocessing techniques for DAB transmissions to mitigate artifacts in PCL.
• To improve the correlation properties of received DAB signals for enhanced PCL performance.
• To assess the impact of preprocessing on range/Doppler plot quality and target detection.

Main Methods:

• Development of signal preprocessing methods including symbol removal, substitution by noise, and symbol duplication at the DAB transmission frame level.
• Experimental evaluation of proposed methods using real DAB signals on a PCL platform.
• Analysis of Signal to Noise Ratio (SNR) for moving target detection and computational complexity.

Main Results:

• Two proposed methods effectively eliminate periodic artifacts in bistatic range/Doppler plots.
• The symbol duplication method demonstrates a significant improvement in SNR, offering approximately 3 dB gain for moving target detection.
• The optimized symbol duplication method is computationally efficient and suitable for practical implementation.

Conclusions:

• Signal preprocessing techniques, particularly symbol duplication, significantly enhance the quality of PCL range/Doppler plots when using DAB signals.
• The proposed methods provide a robust solution for artifact reduction, leading to improved target detection performance in PCL systems.
• The computational efficiency of the symbol duplication method makes it a practical and valuable enhancement for PCL applications utilizing DAB signals.