I/Q Decomposition of Linear Frequency Modulated Signals with MATLAB Implementation

This document provides a comprehensive guide on implementing I/Q decomposition of Linear Frequency Modulated (LFM) signals using MATLAB, with output through low-pass filters. We begin by explaining the definition, applications, and characteristics of LFM signals to establish context for this processing technique. The implementation involves generating complex LFM signals using MATLAB's chirp function or mathematical formulations, then separating them into In-phase (I) and Quadrature (Q) components through quadrature demodulation. For filter implementation, we discuss low-pass filter working principles and parameter selection criteria using MATLAB's filter design functions (fir1, butter, or cheby1) to achieve optimal performance. The processing chain typically includes: signal generation -> quadrature mixing -> low-pass filtering -> component extraction. Finally, we present practical application examples demonstrating how these techniques solve real-world problems in radar systems and communications, with MATLAB code snippets showing key operations like Hilbert transforms for analytic signal generation and filter frequency response verification.