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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.


Understanding the Hogge Detector and the Triwave Solution

Understanding the Hogge Detector and the Triwave Solution

The Hogge phase detector plays multiple roles in CDR circuits. In this article, we'll explore the Hogge detector's behavior, highlight its main drawbacks, and introduce a different configuration that addresses them.


Introduction to Clock and Data Recovery

Introduction to Clock and Data Recovery

Learn how PLLs enable communication in which a clock signal is not transmitted with the data. We’ll look specifically at return-to-zero (RZ) and non-return-to-zero (NRZ) data formats.


Hands-ON With AT Commands: The LoRaWAN Trainer

Hands-ON With AT Commands: The LoRaWAN Trainer

We use a Raspberry Pi and free software to build a test platform for IoT systems.


Projects Mar 02, 2025 by Don Wilcher
The Wireless Alphabet Flasher: A Radio Shack Classics Circuit Remix

The Wireless Alphabet Flasher: A Radio Shack Classics Circuit Remix

In this project, we mix the old and the new by integrating present-day BLE technology with a vintage Science Fair computer kit.


Projects Jul 21, 2024 by Don Wilcher
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.


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.


Building and Certifying an Open-Source IoT Controller, Part 3: Manufacturing and Testing

Building and Certifying an Open-Source IoT Controller, Part 3: Manufacturing and Testing

This four-part series walks through the development of the Anthilla Controller, an open-source Internet of Things (IoT) hardware platform. In Part 3, we cover the manufacturing, assembly, and product testing of the board.


Understanding Bluetooth LE Pairing—Step by Step

Understanding Bluetooth LE Pairing—Step by Step

Pairing is an important concept in Bluetooth LE. Let’s examine the fundamentals of Bluetooth LE pairing, outlining how LE devices securely share keys between trusted devices.


Vulnerabilities and Attacks on Bluetooth LE Devices—Reviewing Recent Info

Vulnerabilities and Attacks on Bluetooth LE Devices—Reviewing Recent Info

To understand known vulnerabilities and attacks on Bluetooth LE devices, we review some studies from the past 4+ years.


Securing BLE Connections—An Overview of the Security Protocol

Securing BLE Connections—An Overview of the Security Protocol

Learn about Bluetooth LE's security features and tools, how to use them, and understand how they keep connections secure.


Breaking Down the BLE Link Layer—The 7 States of Bluetooth LE Radio

Breaking Down the BLE Link Layer—The 7 States of Bluetooth LE Radio

Explore the seven states of the Bluetooth LE radio, how the link layer state machine manages the LE radio, and the roles of these states in wireless communication.


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.