Overview

The signal path includes very high dynamic range data converters along with high performance passive mixers with an excellent Polyphase Harmonic Rejection structure. The included band-tracking pre-selectors eliminate unwanted interference and preserve the dynamic range of the receiver. With its world class strong signal handling capability and incredibly Low Noise, the HF+ Discovery is the ideal companion for All your High Performance Receive Scenarios.

Both the architecture and level of integration achieved in this design allow us to bring top performance reception at a very affordable price. All the major SDR software is supported. Check the download page.

Ready to discover all these signals hiding in your spectrum? 

Improved Architecture

Unrivalled Noise Reduction Processing

We spent a lot of time understanding RF noise, its structure, and how it interacts with legitimate signals. Today, we have one of the most flexible and acoustically pleasant noise reduction algorithms of the market. The applications range from high-fidelity hiss removal for Broadcast FM signals, to unburying weak SSB signals from the noise floor. Our algorithm doesn’t kill the highs to give you a false impression of loudness, yet it doesn’t have the typical high tone artifacts that plague popular noise reduction algorithms like LMS and Spectral Subtraction.

Here’s a very weak SSB signal in the 40m band, with and without our Digital Noise Reduction. Check by yourself!

https://airspy.com/downloads/dnr_ssb.mp3 

Another recording in the 80m during a pileup:

https://airspy.com/downloads/Csete_80m_20171118_231457Z_3765000Hz_AF.mp3 

Audio signal without processing:

Audio signal with our Digital Noise Reduction processing:

New Disruptive Architecture

HF Tuner

Airspy HF+ Discovery achieves excellent HF performance by means of a low-loss preselection filter, high linearity LNA, high linearity tunable RF filter, a polyphase harmonic rejection (HR) mixer that rejects up to the 21st harmonic and multi-stage analog and digital IF filtering.

The 6 dB-stepped AGC gain is fully controlled by the software running in the DSP which optimizes the gain distribution in real time for optimal sensitivity and linearity. Harmonic rejection is a key issue in wide band HF receivers because of the large input signal bandwidth of the input signal. The output of the IF-filter is then digitalized by a high dynamic range sigma delta IF ADC for further signal processing in the digital domain.

IF Sampling

The IF analog to digital converter (ADC) is a 4th order multi-bit noise shaping topology; it features very high dynamic range and linearity. The IF-ADC sampling rate is determined by a control algorithm running in the embedded DSP. This advanced technique adjusts the sampling rate depending on the tuning frequency with the goal of avoiding the disturbances and spurs generated by the switching discrete-time sections of the IF-ADC.

Technical specifications

• HF coverage between 0.5 kHz .. 31 MHz 
• VHF coverage between 60 .. 260 MHz
• -140.0 dBm (0.02 µV / 50 ohms at 15MHz) MDS Typ. at 500Hz bandwidth in HF
• -141.5 dBm MDS Typ. at 500 Hz bandwidth in FM Broadcast Band (64 – 118 MHz)
• -141.0 dBm MDS Typ. at 500 Hz bandwidth in VHF Aviation Band (118 – 260 MHz)
• +15 dBm IIP3 on HF at maximum gain
• +13 dBm IIP3 on VHF at maximum gain
• 110 dB blocking dynamic range (BDR) in HF
• 95 dB blocking dynamic range (BDR) in VHF
• 150+ dB combined selectivity (hardware + software)
• 120 dB Image Rejection (software)
• Polyphase Tracking filters for close range interference suppression
• New High Performance Pre-selector for HF with 4 filter banks (corners at ~DC, 5, 10, 17 and 31 MHz)
• New High Performance Pre-selector for VHF (Air, HAM, Commercial and Military VHF)
• New High Performance Pre-selector for the FM band (Japan, US, EU, OIRT)
• Up to 660 kHz alias and image free output for 768 ksps IQ
• 18 bit Embedded Digital Down Converter (DDC)
• 22 bit Resolution at 3 kHz channel using State of the Art DDC (SDR# and SDR-Console)
• +10 dBm Maximum RF input
• 0.5 ppm high precision, low phase noise clock
• 1 PPB frequency adjustment capability
• Very low phase noise PLL (-110 dBc/Hz @ 1kHz separation @ 100 MHz)
• Best Noise reduction of the market using state of the art algorithms
• 2 x High Dynamic Range Sigma Delta ADCs @ up to 36 MSPS
• Single RF Input to cover all bands with High Linearity switching
• Improved input matching down to virtually DC
• Smart AGC with real time optimization of the gain distribution for Best SNR in all situations
• No drivers required! 100% Plug-and-play on Windows Vista, Seven, 8, 8.1 and 10
• Industrial Operating Temperature: -45°C to 85°C

Typical Applications

• High Performance Networked HF/VHF Radio
• Ham Radio (HF + 2m)
• Short Wave Listening (SWL)
• AM DX
• FM DX
• VHF-L TV DX
• Remote Telemetry Radio Receiver
• Low Bands IoT

Supported Software

• The gold standard SDR#
• The other excellent SDR suite, SDR-Console
• The suiss-army SDR knife for Linux and Mac, GQRX
• Network server for use with SdrDx for Mac, AirspyHF+ Mac ServerGQRX
• All ExtIO based software (HDSDR, Studio1, etc.) via ExtIO by Hayati Ayguen
• All ExtIO based software (HDSDR, Studio1, etc.) via ExtIO by Andrea Montefusco
• Check the full list of tools in our download page

Supported Operating Systems

• Windows Vista, 7, 8, 8.1 and 10
• Linux
• *BSD
• OSX

Supported Hardware

• Intel compatible PC
• Raspberry Pi 2 and 3
• Odroid C1, C2 and XU4
• Many other Single Board Computers (SBC)

Minimum hardware requirements

• 1GHz Pentium or ARM
• 1GB of RAM (to run your own OS, HF+ barely needs 1MB of memory)
• High speed USB 2.0 controller

Fully Open-Source driver

• Open source, multi-platform user mode driver libairspyhf on github

Firmware Updates

• R2.0.0 2019-05-02 (Changelog)