sdrtop – terminal monitor for software-defined radio hardware

sdrtop is a terminal-based monitoring and diagnostic application for software-defined radio (SDR) hardware. It provides real-time information about radio signals and receiver performance through an interactive interface that works in a conventional terminal or remote SSH session.

The application is designed for radio enthusiasts, experimenters and engineers who want to investigate signals and understand how their SDR hardware is performing. It combines spectrum visualisation with detailed measurements of the receiver’s signal chain.

sdrtop supports several radio devices, including HackRF, RTL-SDR and tinySA hardware. It concentrates on measurement and signal inspection rather than audio listening, providing tools for examining modulation, receiver performance and captured IQ data.

This is free and open source software.

Key Features

• Real-time FFT spectrum analyser with peak hold and noise floor tracking.
• Scrolling waterfall display showing changes in frequency activity over time.
• Adjustable frequency tuning, sample rates and receiver gain settings.
• Signal strength monitoring with an analogue-style S-meter display.
• Frequency markers, band-plan overlays and spectrum zoom controls.
• RF measurements including signal-to-noise ratio, occupied bandwidth and adjacent-channel power.
• Receiver diagnostics covering noise figure, sensitivity and ADC loading.
• IQ analysis with DC offset and quadrature correction facilities.
• Timing measurements for investigating sample delivery and processing behaviour.
• Frequency sweeps covering bandwidths wider than the instantaneous receiver spectrum.
• FM and AM modulation analysis, including FM deviation and modulation depth.
• RDS decoding for station names, programme types and RadioText.
• Experimental analysis of Bluetooth Low Energy and classic Bluetooth signals.
• Record raw IQ samples in SigMF format with information about lost samples.
• Observer mode for inspecting hardware information when another application controls the receiver.
• Support for HackRF One, RTL-SDR and tinySA devices, with experimental SoapySDR integration.
• Configurable layouts, compact displays, keyboard controls and colour themes.

Website: github.com/musithang/sdrtop
Support:
Developer: MusiThang and contributors
License: GNU General Public License v3.0

sdrtop is written in Rust. Learn Rust with our recommended free books and free tutorials.

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