Software-defined radio (SDR) has transformed how we interact with radio signals, and SDRBerry aims to push this transformation further. SDRBerry is an ongoing project designed to integrate an SDR transceiver with a Raspberry Pi, leveraging the power of LVGL v8 for a modern GUI experience. While still in development, this project offers a unique learning opportunity in C++ programming, Liquid DSP, and GUI design.

Project Overview

SDRBerry is built with the goal of supporting various SDR devices, including:

• Adalm Pluto SDR
• Radioberry
• RTL-SDR
• SDRPlay
• Other SDR receivers via SoapySDR

The system also aims to integrate optical encoders, I2C/serial-controlled bandpass filters, and an ESP32-based CAT controller for additional hardware control.

Installation Guide

To install SDRBerry, follow these steps:

1. Set up Raspberry Pi OS (64-bit Bullseye) in CLI mode.
2. Use Raspberry Pi Imager to create a bootable SD card or USB stick (USB storage is preferred for longevity).
3. Configure Wi-Fi and enable I2C using raspi-config.
4. Compile the software using VisualGDB, CMake, GCC, and GFortran.
5. Enable remote control with framebuffer VNC using framebuffer-vncserver.

A full installation guide is available in install_guide.txt, and an installation script (install.sh) automates the process.

Hardware Requirements

• Raspberry Pi 4 Model B
• 5-inch or 7-inch 800×480 touchscreen (DSI connector recommended)
• USB storage device (e.g., Samsung Fit Plus 32GB or larger)
• Generic USB audio adapter

Features and Development Progress

Completed Features:

Adalm Pluto, RTL-SDR, SDRPlay, Radioberry, and HackRF support
FM broadband and narrowband reception
SSB transmission and reception
USB CAT interface support (e.g., ESP32 as a CAT controller)
I2C filter support with PCF8574
Noise reduction (ported from DD4WH’s implementation)
Morse code decoder
FT8 transmission and reception
Web-based remote control via Vue.js 3 and PrimeVue UI (experimental)

Upcoming Features:

• MIDI controller support
• Direct optical encoder support via GPIO
• Network and Wi-Fi setup screen
• Additional noise reduction algorithms (e.g., LMS filtering)
• Codec2 implementation for FreeDV digital voice

Installation of Dependencies

SDRBerry relies on several open-source libraries, including:

• Liquid-DSP (Joseph D. Gaeddert)
• Alsa Audio
• SoapySDR and SoapyPlutoSDR
• FFTW (Fast Fourier Transform)
• CivetWeb (embedded web server)
• nlohmann-json (JSON library for C++)

To install and compile the software, use:

wget https://raw.githubusercontent.com/paulh002/sdrberry/master/install/install.sh
chmod +x install.sh
./install.sh HFB DSI

For Raspberry Pi Touch 2 with Radioberry:

./install.sh RDB T2

Running SDRBerry

To start SDRBerry in user mode or root mode (depending on the SDR device used):

sudo sdrberry > sdrberry.log 2>&1

Mouse support is included, with optimized responsiveness via usbhid.mousepoll=2 in cmdline.txt.

Web-Based Control

SDRBerry introduces an experimental web-based remote control on port 8081. The interface, built using Vue.js 3 and PrimeVue UI, allows users to control SDRBerry remotely. The source code will be available in a separate repository.

To access the web interface:

http://raspberry_pi_ip:8081

Conclusion

SDRBerry is an exciting open-source SDR project that integrates Raspberry Pi, LVGL GUI, and SDR technologies. While still in active development, the project offers a strong foundation for experimenting with software-defined radio on a compact and affordable platform.

For more details and the latest updates, visit the SDRBerry GitHub repository:
https://github.com/paulh002/sdrberry

The post Exploring SDRBerry: A Raspberry Pi-Based SDR Transceiver with LVGL GUI appeared on Hamradio.my - Amateur Radio, Tech Insights and Product Reviews by 9M2PJU.

When it comes to setting up a web server, Nginx is a popular choice due to its high performance and low resource usage. Both Ubuntu and FreeBSD are robust operating systems that can host Nginx effectively, but there are differences in how each handles performance, load, memory, and other related aspects. This article will compare Nginx web server performance on Ubuntu and FreeBSD, providing insights into their strengths and weaknesses.

Overview of Nginx

Nginx is an open-source web server known for its high concurrency, performance, and low memory footprint. It is commonly used for serving static content, acting as a reverse proxy, load balancer, and handling HTTP, HTTPS, and other protocols.

Testing Environment

For a fair comparison, we need to set up identical environments on both Ubuntu and FreeBSD:

• Hardware: Identical hardware configurations with equal CPU, RAM, and storage capacities.
• Nginx Version: The same version of Nginx, compiled with similar modules and configurations.
• Workload: The same workload, including the number of concurrent users, request types, and content served.
• Benchmarking Tools: Tools like ApacheBench (ab) and wrk to measure performance metrics such as requests per second, latency, and resource utilization.

Performance Metrics

1. Installation and Configuration

• Ubuntu:
• Installation: sudo apt update && sudo apt install nginx
• Configuration: Nginx on Ubuntu can be easily configured using /etc/nginx/nginx.conf.
• FreeBSD:
• Installation: pkg install nginx or using the Ports Collection.
• Configuration: Nginx configuration on FreeBSD is also located in /usr/local/etc/nginx/nginx.conf.

Ubuntu offers a more straightforward and familiar package management system with apt, while FreeBSD provides more flexibility through its Ports Collection, allowing for customized builds.

2. Requests Per Second (RPS)

This metric measures the number of requests a server can handle per second.

• Ubuntu: Typically, Ubuntu has shown high RPS due to its optimized kernel for general workloads and extensive optimizations available through apt.
• FreeBSD: FreeBSD, with its focus on network performance and efficient TCP/IP stack, often matches or slightly exceeds Ubuntu in RPS, especially under high network loads.

3. Latency

Latency measures the delay before a transfer of data begins following an instruction for its transfer.

• Ubuntu: Generally, Ubuntu exhibits low latency, but this can vary depending on system tuning and specific workloads.
• FreeBSD: Known for its network stack efficiency, FreeBSD can have slightly lower latency, particularly for high throughput scenarios due to optimizations in handling TCP/IP.

4. Memory Usage

Memory usage is crucial for understanding how many resources are consumed under load.

• Ubuntu: Nginx on Ubuntu tends to use a bit more memory due to the default configuration and system services running in the background.
• FreeBSD: Typically uses less memory because of its leaner base system and more granular control over system processes.

5. CPU Utilization

This metric evaluates how efficiently the CPU is used by Nginx under load.

• Ubuntu: Ubuntu’s CPU utilization is efficient, benefiting from years of optimizations and improvements in the Linux kernel.
• FreeBSD: FreeBSD’s CPU utilization can be even more efficient in network-heavy scenarios due to its well-tuned kernel and network stack.

Comparative Analysis

Installation and Ease of Use

• Ubuntu: Easier for beginners and those familiar with Linux. The apt package manager simplifies the installation and update process.
• FreeBSD: Offers more customization through the Ports Collection but has a steeper learning curve.

Performance Under Load

• Ubuntu: Handles web traffic efficiently but might require more tuning for extreme performance needs.
• FreeBSD: Excels in network performance and stability under heavy loads, often outperforming Ubuntu in high-concurrency scenarios.

Memory Efficiency

• Ubuntu: Uses more memory out-of-the-box but provides ample tools and community support for optimization.
• FreeBSD: Generally more memory-efficient due to its streamlined base system.

Security and Stability

• Ubuntu: Regular updates and a large support community ensure security patches and stability.
• FreeBSD: Known for its rigorous security measures and stability, making it a preferred choice for critical applications.

Conclusion

Both Ubuntu and FreeBSD are capable of running Nginx with high performance, but they cater to different needs and preferences:

• Ubuntu: Ideal for users who prefer ease of use, extensive software repositories, and community support. It performs well under most web server loads and is easier to set up and maintain.
• FreeBSD: Preferred for high-performance, high-stability environments, particularly where network performance is critical. Its efficient memory usage and robust security features make it an excellent choice for demanding web server applications.

Ultimately, the choice between Ubuntu and FreeBSD for hosting an Nginx web server will depend on your specific requirements, expertise, and the particular demands of your workload. Both operating systems offer unique advantages that can be leveraged to optimize web server performance.

The post Ubuntu vs. FreeBSD: Nginx Web Server Performance Comparison appeared on Hamradio.my - Amateur Radio, Tech Insights and Product Reviews by 9M2PJU.