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Analyzing the Noise Performance of Coherent SSB Demodulators

Analyzing the Noise Performance of Coherent SSB Demodulators

Using a graphical approach, we show that coherent SSB demodulation leaves the input and output SNR unchanged, then compare its noise performance to DSB-SC and baseband systems.


A Four-Channel RS-422 Differential Line Receiver Module

A Four-Channel RS-422 Differential Line Receiver Module

This project brief describes how to build and use a four-channel differential line receiver module for balanced RS-422 and RS-485 data links.


Understanding SNR in DSB‑SC Coherent Detection: A Graphical Approach

Understanding SNR in DSB‑SC Coherent Detection: A Graphical Approach

Visualizing how correlated and uncorrelated signals combine offers an intuitive look at power transformation. See how this difference boosts baseband power to double the output SNR.


A Four-Channel RS-422 Differential Line Driver Module

A Four-Channel RS-422 Differential Line Driver Module

This project brief describes how to implement a four-channel differential line driver module for reliable long-distance data transmission over balanced twisted-pair lines.


Evaluating the Noise Performance of Coherent DSB‑SC Demodulators

Evaluating the Noise Performance of Coherent DSB‑SC Demodulators

In this article, we'll learn how to calculate the noise power and signal-to-noise ratio (SNR) of a double-sideband suppressed-carrier communication system.


Common-Mode Noise in Differential Transmissions: Characteristics and Causes

Common-Mode Noise in Differential Transmissions: Characteristics and Causes

High-speed data transmission interfaces such as USB, HDMI, and Ethernet use differential signaling due to its superior noise immunity. Even so, some noise still appears. To remove it, we need to understand where it comes from and why.


What’s the Difference Between RS-232 and RS-485?

What’s the Difference Between RS-232 and RS-485?

Though both standards have long been used for serial communication, RS-485 offers valuable features that aren't available from RS-232. Learn more in this article.


Understanding the Significance of Dynamic Range and Spurious-Free Dynamic Range

Understanding the Significance of Dynamic Range and Spurious-Free Dynamic Range

In this article, we investigate two metrics used to characterize the performance of RF test and measurement systems.


Understanding the Inner Workings of Vector Network Analyzers

Understanding the Inner Workings of Vector Network Analyzers

In this article, we explore how the signal source and receivers of a VNA enable its function.


Understanding RF Power Measurement Errors in Directional Couplers

Understanding RF Power Measurement Errors in Directional Couplers

Directional couplers are valuable tools for testing RF systems. However, the finite directivity of these devices can cause measurement uncertainty. Learn more in this article.


Introduction to the Class B Power Amplifier

Introduction to the Class B Power Amplifier

How does a Class B power amplifier work? What makes it more efficient than a Class A power amplifier? Learn the answers in this article.


Learn About Load-Pull Systems: Passive and Active Tuners

Learn About Load-Pull Systems: Passive and Active Tuners

In this article, we explore the types of impedance tuners most commonly used for load-pull measurement—their advantages, their disadvantages, and the methods by which they synthesize impedance.


Using the Load-Pull Technique in RF Power Amplifier Design

Using the Load-Pull Technique in RF Power Amplifier Design

The output power and efficiency of a power amplifier (PA) are highly dependent on its load terminations. Learn how to characterize a PA's performance by analyzing load lines and estimating the load-pull contours of constant output power.


Characterize RF Noise Components Using Equivalent Noise Temperature

Characterize RF Noise Components Using Equivalent Noise Temperature

Learn another way to characterize RF noise components using noise temperature and how this concept clears up how noise figure measurement instruments actually work.


Understanding the RF Noise Figure Specification

Understanding the RF Noise Figure Specification

Take a closer look at the definition of the RF noise figure and discuss some subtleties to help avoid erroneous interpretations of this specification.


Design a Two-element Matching Network Using the ZY Smith Chart

Design a Two-element Matching Network Using the ZY Smith Chart

Learn about the immittance Smith chart (ZY Smith chart), the effect of adding series and parallel components, impedance matching, and finding a two-element matching network.


Exploring the Basics of Bluetooth Low Energy: A Beginners Guide To BLE

Exploring the Basics of Bluetooth Low Energy: A Beginners Guide To BLE

Learn about the Bluetooth low energy (BLE) wireless communication protocol, namely its features, protocol stack, and how it communicates with devices.


RF Design Basics: VSWR, Return Loss, and Mismatch Loss

RF Design Basics: VSWR, Return Loss, and Mismatch Loss

Learn about voltage standing wave ratio (VSWR), return loss, and mismatch loss, which helps characterize the wave reflections in a radio frequency (RF) design.


Introduction to CAN (Controller Area Network)

Introduction to CAN (Controller Area Network)

This article introduces the Controller Area Network (CAN) serial communication bus, detailing message frames, bus arbitration, and signaling.


Understanding Bandwidth in Communications and Computing

Understanding Bandwidth in Communications and Computing

This article discusses how to interpret and specify bandwidth in systems that involve data transmission and digital processing.