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Practical Insights Into Narrowband FM With a Single-Frequency Input

Practical Insights Into Narrowband FM With a Single-Frequency Input

In this article, we’ll use phasor diagrams to compare narrowband FM and conventional AM. We’ll also discuss the problem of oscillator phase noise and work through an example problem.


Introduction to Narrowband Angle Modulation

Introduction to Narrowband Angle Modulation

Using a simple example, this article examines the frequency spectra of frequency-modulated (FM) and phase-modulated (PM) waves for a low modulation index.


Understanding the Differences Between Phase and Frequency Modulation

Understanding the Differences Between Phase and Frequency Modulation

Learn why phase modulation (PM) and frequency modulation (FM) can produce waveforms that are nearly identical or completely different from one another, depending on the nature of the message signal.


A Guide to Calculating IM3 and IP3 for Nonlinear RF Circuits

A Guide to Calculating IM3 and IP3 for Nonlinear RF Circuits

Learn to confidently determine intermodulation distortion products and the third-order intercept point of RF circuits by working through a selection of example problems.


Startup Intros ‘Most Advanced’ Multi-Gigahertz Timing and Clock Devices

Startup Intros ‘Most Advanced’ Multi-Gigahertz Timing and Clock Devices

Unveiled today, the new timing chips from Mixed-Signal Devices offer 2 GHz performance and use scalable CMOS to overcome the limits of analog alternatives.


News Jun 03, 2025 by Jeff Child
Using Instantaneous Frequency to Represent PM and FM Signals

Using Instantaneous Frequency to Represent PM and FM Signals

In this article, we’ll explore the mathematical relationship between phase modulation (PM) and frequency modulation (FM). We’ll then learn how a PM modulator can be used to generate FM signals, and vice versa.


Understanding Intermodulation Distortion and the Third-Order Intercept Point In RF Systems

Understanding Intermodulation Distortion and the Third-Order Intercept Point In RF Systems

Learn how the two-tone input test helps us evaluate the nonlinearity of RF systems operating on real-world signals.


Introduction to Phase Modulation for RF Systems

Introduction to Phase Modulation for RF Systems

In this article, we introduce the basic principles of phase modulation (PM) and use example waveforms to clarify the often-confusing relationship between the PM wave and the message signal.


Exploring the Operation of the Weaver Modulator for Single-Sideband Modulation

Exploring the Operation of the Weaver Modulator for Single-Sideband Modulation

Using graphical representations to support our mathematical analysis, we walk through the process of how the Weaver modulator transforms the signal frequency spectrum.


Introduction to Weaver’s Method for SSB Signal Generation

Introduction to Weaver’s Method for SSB Signal Generation

Learn about the Weaver modulator, an RF circuit that improves on older forms of SSB modulation by removing the need for either sharp bandpass filters or quadrature phase shifters.


How Phasors Help Us Understand Bandpass Signals

How Phasors Help Us Understand Bandpass Signals

Using phasors, we explore how real-valued bandpass signals are represented as complex baseband signals in the models used by RF communication systems.


A Visual Approach to Understanding the Phasing Method for SSB Modulation

A Visual Approach to Understanding the Phasing Method for SSB Modulation

This article uses 3D models of the frequency spectrum to demystify the complex mathematical concepts, such as the Hilbert transform and the shifting property, that make the phasing method possible.


The Phasing Method and Hilbert Transforms for Single-Sideband Modulation

The Phasing Method and Hilbert Transforms for Single-Sideband Modulation

SSB modulation improves bandwidth efficiency by eliminating either the upper or lower sideband. Learn about the circuits and mathematics that make this possible without the use of sharp filters.


Introduction to Single-Sideband Modulation: The Filter Method

Introduction to Single-Sideband Modulation: The Filter Method

Learn about a classic amplitude modulation (AM) technique that’s been used in voice transmission for nearly a century.


Demodulating Double-Sideband AM Signals

Demodulating Double-Sideband AM Signals

We examine RF demodulation circuits used for both double-sideband suppressed carrier (DSB-SC) signals and double-sideband signals with a carrier.


Four Interesting AM Modulation Circuits You Should Know About

Four Interesting AM Modulation Circuits You Should Know About

This article highlights a selection of circuits used for amplitude modulation, including a switching modulator built with just one diode and a circuit that incorporates a Class C power amplifier.


Understanding How Ring Modulators Produce AM Signals

Understanding How Ring Modulators Produce AM Signals

Among modulator circuits, the ring modulator stands out as one of the most effective for generating AM signals. Learn why in this article.


How Do Switching Modulators Generate AM Signals?

How Do Switching Modulators Generate AM Signals?

Using the example of a diode-bridge modulator, we examine the basic principles of switching modulators for AM signal generation.


Introduction to the Balanced Modulator for AM Signals

Introduction to the Balanced Modulator for AM Signals

Learn how the balanced modulator addresses shortcomings of the square-law modulator when generating DSB-SC and conventional AM signals.


Understanding the Square-Law Modulator for Generating AM Signals

Understanding the Square-Law Modulator for Generating AM Signals

In this article, we explore the foundational concepts of square-law modulators and examine some circuit implementations.