Tag: Frequency Modulation (FM)

A discrete-time FM demodulator block diagram with atan2 and derivative filter
DSP / Wireless/SDR

Frequency Modulation (FM) and Demodulation Using DSP Techniques

Frequency Modulation (FM) is as old as the history of wireless communications itself. The past few decades saw the rise of digital signal processing in all spheres of life that pervaded even the implementation of analog modulation schemes. Today many of the FM systems are built using discrete-time techniques instead of the conventional circuitry as described below. Frequency Modulation In digital communications, data is sent through altering a characteristic of an electromagnetic wave such as amplitude, frequency or phase in discrete steps (e.g., $M$ number of levels). Such systems are known as Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK)

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Projections of a sphere in Flatland
DSP

Two Birds with One Tone: I/Q Signals and Fourier Transform – Part 2

In Part 1 of I/Q signals series, we discussed in detail the orthogonality in phase and saw how this leads us to employing two carriers in wireless transmission systems. In Part 2, we talk about orthogonality in frequency and see how this leads us to the concept of Fourier Transform. A Basic Building Block We use the power of logic to uncover the rules according to which the world works. But our minds struggle to retain excessive amounts of information required to grasp the complex reality. Therefore, we like to reduce everything around us as a combination of some fundamental

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