The aperture effect rolls off high message frequencies in flat-top PAM. Here’s how pulse duration limits that distortion to under 0.5% and when an equalizer helps.
The aperture effect rolls off high message frequencies in flat-top PAM. Here’s how pulse duration limits that distortion to under 0.5% and when an equalizer helps.
Flat-top PAM holds each sample’s amplitude for the pulse duration, weighting the spectrum with a sinc function.…
Flat-top PAM holds each sample’s amplitude for the pulse duration, weighting the spectrum with a sinc function. Here’s how that weighting leads to the aperture effect.
Multiplying a message by a pulse train replicates its spectrum at every harmonic. See why a 1/3 duty cycle and 4x…
Multiplying a message by a pulse train replicates its spectrum at every harmonic. See why a 1/3 duty cycle and 4x oversampling stretch the bandwidth roughly 12-fold.
This project brief describes how to build and use an Arduino-compatible interface board that reads an on-board pressure…
This project brief describes how to build and use an Arduino-compatible interface board that reads an on-board pressure sensor and reports the measurement over an RS-485 network.
This project brief describes how to build and use an Arduino-compatible interface board that reads a 2-axis thumb…
This project brief describes how to build and use an Arduino-compatible interface board that reads a 2-axis thumb joystick and transmits its position over an RS-485 network.
This project brief describes how to build and use an Arduino-compatible relay interface board that switches a 10 A load…
This project brief describes how to build and use an Arduino-compatible relay interface board that switches a 10 A load over an RS-485 network.
This project brief describes how to build and use an Arduino-compatible board that reads a linear Hall-effect sensor and…
This project brief describes how to build and use an Arduino-compatible board that reads a linear Hall-effect sensor and reports the measurement over an RS-485 bus.
Envelope detection is simple, but that simplicity has a noise-performance cost. Here’s how much SNR conventional AM…
Envelope detection is simple, but that simplicity has a noise-performance cost. Here’s how much SNR conventional AM gives up compared to its coherent counterparts.
Using a graphical approach, we show that coherent SSB demodulation leaves the input and output SNR unchanged, then…
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.
This project brief describes how to build and use a four-channel differential line receiver module for balanced RS-422…
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.
Visualizing how correlated and uncorrelated signals combine offers an intuitive look at power transformation. See how…
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.
This project brief describes how to implement a four-channel differential line driver module for reliable long-distance…
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.
In this article, we'll learn how to calculate the noise power and signal-to-noise ratio (SNR) of a double-sideband…
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.
The Hogge phase detector plays multiple roles in CDR circuits. In this article, we'll explore the Hogge detector's…
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.
Learn how PLLs enable communication in which a clock signal is not transmitted with the data. We’ll look specifically…
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.
We use a Raspberry Pi and free software to build a test platform for IoT systems.
We use a Raspberry Pi and free software to build a test platform for IoT systems.
In this project, we mix the old and the new by integrating present-day BLE technology with a vintage Science Fair computer kit.
In this project, we mix the old and the new by integrating present-day BLE technology with a vintage Science Fair computer kit.
High-speed data transmission interfaces such as USB, HDMI, and Ethernet use differential signaling due to its superior…
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.
Though both standards have long been used for serial communication, RS-485 offers valuable features that aren't available…
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.
How does a Class B power amplifier work? What makes it more efficient than a Class A power amplifier? Learn the answers…
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.