Additional Software
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Khanfar IQ Live-Rec-Playback
Professional IQ Data Recording, Visualization, and Playback Solution for RTL-SDR
Software Overview
Khanfar RTL-SDR IQ Live+Rec+Playback is a powerful, feature-rich spectrum analyzer application designed for RTL-SDR devices. This professional-grade software provides real-time RF spectrum visualization with GPU-accelerated rendering, comprehensive IQ data recording capabilities in multiple industry-standard formats, and advanced playback features for signal analysis. With IQEngine and IQ Analyzer integration, you can seamlessly export your recorded signals for comprehensive online analysis, visualization, and collaboration.
Key Features
Professional IQ Data Management
- Multi-Format Recording: Record IQ data in Raw IQ, VITA-49, SigMF, CF32, Complex, IQData, CDIF, or DGZ formats
- One-Click Recording: Instantly capture raw IQ data with a single button press
- Comprehensive Metadata: Automatically stores frequency, gain, and device information
- Tuning History Capture: Records and replays frequency/gain changes during recordings
- Efficient File Management: Automatically generates timestamped filenames with frequency information
Advanced Playback Capabilities
- Seamless File Loading: Simple interface to load and analyze previously recorded signals
- Automated Tuning Replay: Automatically replays tuning sequences exactly as recorded
- Visualization During Playback: Full spectrum analysis capabilities maintained during playback
- Safe Mode Switching: Guided process for switching between live and playback modes
Industry-Standard Format Support
- Raw IQ: Traditional complex I/Q data format for maximum compatibility
- VITA-49: Standard RF transport protocol format used in defense and professional applications
- SigMF: Signal Metadata Format for seamless integration with IQEngine.org and other tools
- CF32/Complex/IQData: Standard formats compatible with IQ Analyzer web tool
- CDIF: Complex Data Interchange Format with 32-bit precision for analysis compatibility
- DGZ: Specialized format for compatibility with professional RF analysis software
Web Tool Integration
- IQEngine.org: Direct upload capability for SigMF recordings
- IQ Analyzer: One-click access to IQ Analyzer web tool for CF32, Complex, IQData, and CDIF files
- Professional Analysis: DGZ format compatibility with industry-standard RF analysis tools
Robust Engineering
- Stable Flowgraph Management: Proper start/stop/restart controls for processing
- Extensive Error Handling: Comprehensive recovery mechanisms for unexpected conditions
- Dynamic Component Management: Graceful fallbacks when components are unavailable
Real-Time Spectrum Analysis
- High-Performance Visualization: Utilizes GPU-accelerated gr-fosphor for fluid, responsive spectrum display
- Comprehensive Frequency Range: Full coverage of RTL-SDR capabilities (24-1766 MHz)
- Fixed 2.4 MHz Sample Rate: Optimized for ideal balance between performance and detail
Advanced Tuning Controls
- Precision Frequency Tuning: Adjustable via slider or direct numerical input
- RF Gain Control: Full adjustment range (0-50 dB) with real-time response
- Multi-Device Support: Seamlessly switch between multiple RTL-SDR devices
Usage Guide
Basic Operation
- Starting the Software: Run the application and wait for the initialization screen to disappear
- Tuning: Adjust the frequency using the slider or by entering a specific value
- Gain Control: Adjust the RF gain to optimize signal reception
- Device Selection: If multiple devices are available, select the desired RTL-SDR from the dropdown
Recording IQ Data
- Select Format: Choose between Raw IQ, VITA-49, SigMF, CF32, Complex, IQData, CDIF, or DGZ recording formats
- Start Recording: Click "Start Recording" to begin capturing IQ data
- Adjust Parameters: Frequency and gain can be adjusted during recording
- Review Status: The status indicator will show the current recording file
- Stop Recording: Click "Stop Recording" when finished
Important Note: Recording files are located in the same directory as the software.
Playback
- Load File: Click "Load IQ File" and select a previously recorded file (Raw IQ, CF32, Complex, IQData, or DGZ formats)
- Tuning History: If tuning history is detected, it will be automatically replayed
- Live View: Click "Return to Live" to exit playback mode and return to live RTL-SDR input
Flowgraph Controls
- Start Flowgraph: Begin signal processing and visualization
- Stop Flowgraph: Pause processing to reduce CPU/GPU usage
- Restart Flowgraph: Reinitialize signal processing for troubleshooting
Advanced Features
Multi-Device Support
The software automatically detects all connected RTL-SDR devices and allows switching between them without restarting the application. This is particularly useful for comparative analysis or when using multiple antennas.
Automatic Metadata Generation
During recording, comprehensive metadata is saved alongside the IQ data, including:
- Frequency
- Sample rate
- Gain settings
- Timestamp
- Device information
- Complete tuning history
Tuning History Replay
When a recording with tuning history is loaded, the software will automatically replay the exact frequency and gain adjustments made during recording, allowing perfect reproduction of the original analysis session.
File Formats
Raw IQ (*.raw/*.dat)
Traditional format storing interleaved complex values (I and Q components). These files can be processed by other SDR software that accepts raw IQ data. Supports both recording and playback.
VITA-49 (*.vita49)
The VITA Radio Transport (VRT) standard is a protocol designed for the transport of digitized RF data, with standardized metadata and context information. Features include:
- Standardized packet format with header, context, and payload sections
- Embedded metadata: frequency, sample rate, and bandwidth information
- Industry-standard format used in defense and professional RF applications
- Recording only (playback not supported)
SigMF (*.sigmf-data/*.sigmf-meta)
Signal Metadata Format (SigMF) is an open specification for storing recorded signal data and metadata. Features include:
- Split structure: data file (*.sigmf-data) and metadata file (*.sigmf-meta)
- Comprehensive standardized metadata in JSON format
- Frequency change annotations for tuning history
- Direct upload compatibility with IQEngine.org for online analysis
- Recording only (direct playback not supported)
CF32 (*.cf32)
Standard complex float 32-bit format widely used in signal processing applications. Features include:
- Direct compatibility with IQ Analyzer web tool
- Interleaved complex values (I and Q components)
- Full 32-bit floating point precision
- Supports both recording and playback
Complex (*.complex)
Common extension for complex float data used by many SDR applications. Features include:
- Compatible with IQ Analyzer and other signal processing tools
- Identical internal format to CF32 (32-bit complex float)
- Widely recognized by third-party analysis software
- Supports both recording and playback
IQData (*.iqdata)
Standard format for IQ analyzer and other signal processing tools. Features include:
- Optimized for web-based analysis tools
- Compatible with IQ Analyzer web application
- 32-bit complex float precision
- Supports both recording and playback
CDIF (*.cdif)
Complex Data Interchange Format is a standardized container for complex samples. Features include:
- 32-bit complex float precision (standard for IQ Analyzer compatibility)
- Header with metadata including frequency and sample rate
- Timestamp information
- Recording only (direct playback not supported)
DGZ (*.dgz)
A specialized IQ data format designed for compatibility with professional signal analysis tools. Features include:
- Professional Tool Compatibility: Compatible with industry standard RF analysis software
- Advanced Metadata Structure: Includes frequency, bandwidth, timestamp, and system parameters
- Comprehensive Signal Information: Preserves detailed signal characteristics for in-depth analysis
- Lossless Compression: Optional compression to reduce file size without sacrificing data quality
- Recording and playback: Full support for both operations
DGZ Format Details
DGZ format stores complex IQ samples with an advanced header structure containing:
- Signal center frequency and bandwidth information
- Sample rate and duration data
- Timestamp and geolocation data (when available)
- Hardware configuration parameters
- Optional spectrum measurement results
DGZ Technical Specifications
- Data Structure: Binary format with standardized header followed by IQ sample blocks
- Sample Format: Complex 32-bit floating point (16-bit I/16-bit Q optional for space efficiency)
- Endianness: Little-endian for compatibility with modern analysis systems
- Maximum File Size: Limited only by storage medium
- Feature Support: Recording and playback compatible
Metadata Files (*.meta)
Text files containing key information about recordings, including frequency, sample rate, gain, timestamp, and tuning history. These files enable the software to accurately reproduce recording conditions during playback.
Technical Specifications
- Sample Rate: Fixed 2.4 MHz (2.4 MSps)
- Frequency Range: 24-1766 MHz (hardware dependent)
- RF Gain Range: 0-50 dB (hardware dependent)
- Visualization: GPU-accelerated fosphor with standard GNU Radio fallback
- Recording Formats: Raw IQ, VITA-49, SigMF, CF32, Complex, IQData, CDIF, and DGZ with comprehensive metadata
- Supported Devices: All RTL-SDR hardware
Format Compatibility Matrix
| Format | Recording | Playback | External Tools Compatibility |
|---|---|---|---|
| Raw IQ | ✅ | ✅ | Compatible with most SDR software |
| VITA-49 | ✅ | ❌ | Compatible with professional RF systems and analysis tools |
| SigMF | ✅ | ❌ | Direct upload to IQEngine.org and compatible with SigMF-aware tools |
| CF32 | ✅ | ✅ | Compatible with IQ Analyzer and most SDR software |
| Complex | ✅ | ✅ | Compatible with IQ Analyzer and most SDR software |
| IQData | ✅ | ✅ | Compatible with IQ Analyzer and specialized tools |
| CDIF | ✅ | ❌ | Compatible with IQ Analyzer and specialized tools |
| DGZ | ✅ | ✅ | Compatible with professional RF analysis software |
System Requirements
- Operating System: Windows
- Hardware:
- RTL-SDR compatible USB device
- GPU recommended for optimal fosphor visualization
External Tools Integration
IQEngine.org Integration
IQEngine.org is a powerful open-source web application designed for signal processing professionals and RF enthusiasts. It provides advanced visualization, analysis, and collaboration tools for recorded IQ data. Our software seamlessly integrates with IQEngine.org, allowing you to:
- Visualize signals with sophisticated spectrogram, waterfall, and constellation displays
- Perform detailed analysis with built-in signal processing tools
- Share recordings with collaborators or the RF community
- Add annotations to document signal characteristics and findings
- Access your recordings from any device with a web browser
Important: To analyze captured signals with IQEngine, you must record using SigMF format, then click the "IQEngine" button in the GUI. This will prepare your files for upload. When using IQEngine.org, you'll need to upload two files: the sigmf-data and sigmf-meta files. You can upload them either by selecting "Local Directory Upload" or "Local File Pair" in the IQEngine interface.
Files recorded in SigMF format can be directly uploaded to IQEngine.org for advanced online analysis, sharing, and visualization. The application automatically generates SigMF-compliant metadata including:
- Core signal parameters (frequency, sample rate, etc.)
- Annotations for frequency changes
- Timestamp information
- Device details
IQ Analyzer Integration
IQ Analyzer is a versatile web-based tool for analyzing and visualizing IQ data. Our software provides seamless integration with IQ Analyzer through one-click access and optimized format support. With IQ Analyzer, you can:
- Analyze signals using interactive waterfall and spectrum displays
- Measure signal parameters with built-in measurement tools
- Process signals with various filtering and analysis options
- View time-domain and frequency-domain representations simultaneously
- Use from any device with a modern web browser
Important: For IQ Analyzer compatibility, record your signals in CF32, Complex, IQData, or CDIF formats. When recording is complete, click the "I/Q Analyzer" button in the application to open the web tool directly. For best results, use the 32-bit formats which provide full floating-point precision.
Files recorded in CF32, Raw, Complex, IQData, or CDIF formats can be directly analyzed using the IQ Analyzer web application. Features include:
- One-click access to the IQ Analyzer web tool
- Automatic identification of compatible formats
- Comprehensive visualization options
- Support for signal measurements and analysis
VITA-49 Professional Applications
The VITA-49 Radio Transport (VRT) standard is a widely adopted protocol in professional and military signal processing environments. By supporting VITA-49 recording, our software enables integration with sophisticated signal processing ecosystems used in:
- Defense and Intelligence: Signal intelligence (SIGINT) platforms, electronic warfare systems, and tactical communications analysis
- Aerospace: Satellite communications monitoring, aerospace testing, and telemetry systems
- Research: Academic and industry RF research requiring standardized data exchange
- Regulatory: Spectrum compliance monitoring and enforcement systems
- Commercial: Telecommunications testing, RF interference detection, and cellular network analysis
The VITA-49 format provides a structured framework for exchanging digitized RF data between different systems and components, ensuring interoperability across diverse signal processing platforms and vendors.
VITA-49 recordings can be used with professional RF analysis tools that support the standard, including:
- Military and defense signal analysis systems
- Professional spectrum monitoring solutions
- Advanced signal processing frameworks
- High-end RF test and measurement equipment
- Complex signal classification and identification systems
Professional RF Analysis Tool Compatibility
The DGZ format enables compatibility with professional RF analysis applications, creating a bridge between affordable RTL-SDR hardware and advanced signal analysis capabilities. With this format support, you can:
- Conduct detailed signal analysis using professional tools
- Examine modulation characteristics with specialized visualizations
- Perform in-depth quality measurements on captured signals
- Access advanced signal processing features available in professional software
Important: To analyze captured signals with professional RF analysis tools, record your data using the DGZ format.
Legal Information: DGZ format enables compatibility with various professional RF analysis tools, including Anritsu MX280005A IQ Signal Master software. This software is not affiliated with, endorsed by, or sponsored by Anritsu Corporation or any third-party software mentioned. All product names, logos, and brands are property of their respective owners. All company, product and service names used are for identification purposes only.
Additional Information: For more information about Anritsu MX280005A IQ Signal Master software, you can visit Anritsu's official product page.
The DGZ format provides a path for hobbyists and professionals to utilize RTL-SDR hardware with advanced analysis capabilities typically found in expensive test equipment, making it valuable for:
- Signal identification and classification
- Modulation analysis
- Signal quality measurement
- Detailed spectral analysis
- Educational and research purposes
Note: Various professional RF analysis tools offer free or trial versions that can be used with DGZ format files. Check the respective software vendors' websites for availability and limitations.
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