Design and Implementation of an Enhanced Matched Filter for Sidelobe Reduction of Pulsed Linear Frequency Modulation...

Area of Science:

• Radar Systems Engineering
• Signal Processing
• Electromagnetics

Background:

• Pulsed radars utilize linear frequency modulated (LFM) waveforms for enhanced signal-to-noise ratios (SNRs) and range resolution.
• Sidelobes in radar detection can degrade performance, necessitating effective reduction techniques.
• Existing methods for sidelobe reduction often involve iterative or adaptive approaches, impacting computational efficiency.

Purpose of the Study:

• To design and implement an efficient sidelobe reduction filter (SRF) for pulsed radar systems.
• To propose and validate an enhanced matched filter (EMF) by integrating a novel SRF with a traditional matched filter (MF).
• To evaluate the performance of the EMF against conventional methods, particularly for detecting targets with low speeds and small radar cross-sections (RCS).

Main Methods:

• Development of a sidelobe reduction filter (SRF) using software-defined radio (SDR).
• Mathematical modeling of the SRF frequency response without iterative or adaptive techniques for enhanced computational speed.
• Implementation and performance evaluation of the proposed enhanced matched filter (EMF) combining MF and SRF.
• Analysis of Doppler effects using the ambiguity function.

Main Results:

• The proposed EMF demonstrated effective sidelobe reduction, overcoming target masking issues.
• Performance metrics including peak sidelobe ratio (PSLR), impulse response width (IRW), mainlobe loss ratio (MLR), and receiver operational characteristics (ROCs) were analyzed.
• The EMF outperformed the common MF in detecting low-speed targets with small RCS, even under severe masking conditions.
• The mathematical model for the SRF achieved increased efficiency and computational speed.

Conclusions:

• The developed EMF provides a practical and efficient solution for improving pulsed radar detection capabilities.
• The novel SRF design offers a computationally faster alternative to existing sidelobe reduction methods.
• The EMF's superior performance in challenging scenarios validates its effectiveness for real-world radar applications.