High Performance Communications Receiver (Coming Soon!)

Over the past two decades, the collaborative efforts of RF chip manufacturers and software developers have made Software Defined Radios (SDRs) widely accessible. Yet, in the realm of High-Performance, they remain underutilized. Despite the proliferation of high-speed, high bit-width AD Converters and increasingly powerful FPGAs, top-tier professional receivers and transceivers often limit their SDR capabilities to spectrum visualization, while retaining analog RF-IF transformations. The reason? A relentless pursuit of High-Performance.

Enter our innovative Hybrid HF SDR architecture. A few years ago, we revolutionized the market with the introduction of the Airspy HF+ Dual Port, blending a High-Performance Harmonic Rejection Mixer, high-speed ADC, and advanced DSP. This groundbreaking product exceeded all expectations and became an instant success. Building on this momentum, we launched the Airspy HF+ Discovery, which incorporated numerous RF and software enhancements. Both models have garnered global acclaim, earning prestigious awards and glowing reviews, thanks to their innovative focus on a sensible bandwidth-performance balance, which defied mainstream market trends of ever-expanding bandwidth and diminishing performance.

The Airspy Ranger is a natural extension of our HF+ series, expanding the frequency coverage from 0.5 kHz to 1.75 GHz without compromising the much sought-after performance of the HF+ series. It is a VLF/LF/MF/HF/VHF/UHF SDR with an improved front-end, extended gain control, more accurate AGC and a state-of-the-art DSP.

You liked the HF+ Discovery? The Airspy Ranger improves the reception performance even further with extra pre-selectors for all the supported bands and a redesigned front-end to improve the sensitivity and strong signal handling. The IF filtering parameters are controlled in real-time by the DSP to keep the gain distribution optimal and interference-free.

The HF 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 the unwanted interference and preserve the dynamic range of the receiver. The added noise-free RF routing and the manual input attenuation offer world class strong signal handling capability and incredibly Low Noise.

The VHF/UHF path includes band-tracking pre-selectors, a low-noise, high IP3 amplifier, noise-free RF routing, a Low-IF down-converter and manual input attenuation. The down-converter is the same used in our gold standard R2 model with a completely redesigned software control to match the performance of the IF stage.

The main clocking system has also been redesigned with the inclusion of a new low phase noise VC-TCXO unit with its dedicated calibration DAC. The clock distribution is articulated around a low phase noise PLL which improves the RMDR over the previous generations.

Both the architecture and level of integration achieved in this design allow us to bring Professional Communications Receivers performance at an affordable price. All the major SDR software is supported. Check the download page.

High Level Architecture

HF Tuner

Airspy Ranger achieves an 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.

VHF Tuners

Excellent FM performance is also achieved by using optimized signal paths composed of band filters, high linearity LNAs with a stepped AGC, a polyphase harmonic rejection mixer and IF filters optimized for the FM broadcast bands.
The amplifier gain is switchable in 2 dB-steps and fully controlled by the AGC running in the DSP. The RF signal is converted to baseband by a high linearity passive mixer with a polyphase harmonic rejection structure. The Zero-IF signal is then converted into the digital domain by the same Complex IF ADC used in the HF chain.
Extended VHF coverage is assured by a second Band-III tuner up to 260 MHz through a separate filtered path with a dedicated low-noise pre-amplifier.

UHF Tuner

A high-performance down-converter is built around the Rafael Micro R860 with a newly developed control software to operate in its optimal region. The resulting dynamic range is in excess of 100 dB. The AGC loop is fully integrated with the high dynamic range IF circuit. Additionally, a set of pre-selection filters and a high IP3, low-noise pre-amplifier ensure resilient operation even under challenging conditions.

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.

Digital Down Converter

Once the IF signal is digitalized, the high sample rate I/Q stream is then frequency translated and processed with cascaded CIC and FIR decimation stages. After every stage, the sample rate is reduced and the resolution increased. The final signal at the output has 18bit resolution and an alias rejection performance of 108 dBc. The data is then scaled to 16bit and sent to the Micro-Controller for streaming over USB.

Advanced Automatic Gain Control

The Airspy Ranger boasts one of the most sophisticated HF front-ends of the market with multiple AGC loops at different stages to achieve the best gain distribution possible. There are many AGCs at different levels:

Analog:

  • RF AGC, which activates a 6dB (HF) or 2dB (VHF) stepped attenuators,
  • Down-Converter AGC, which controls the gain of the LNA, Mixer and IF for the UHF bands,
  • Analog Zero-IF AGC, which controls the IF gain just before the digitization.

Digital:

  • Digital IF AGC, to ensure the data is scaled properly before sending to the computer,
  • Narrow band AGC (software)

Important Notes:

  • The Digital IF AGC is always activated and only starts acting when the strongest signal(s) in the IF spectrum exceed -6 dBFS. This mechanism ensures your signals are always scaled properly for unattended operations.
  • The RF AGC can no longer be turned off. Instead, a user controlled 4dB stepped attenuator is available at each RF input.
  • The AGC threshold is controlled internally and is no longer exposed.
  • The preamp option was replaced by a user controlled 4dB stepped attenuator.

CNC Machined Aliminium Enclosure

The different RF and Digital sections of the Airspy Ranger live inside their respective cavities carved on the same chunk of aluminium. Multiple screws on the bottom of the enclosure ensure firm contact. The inside of each cavity is coated with a high tech EMI-absorbing material to prevent unwanted reflections. The resulting RF isolation is in excess of 100 dB in all the bands, and the high-end feel is guaranteed.

Technical specifications

  • Frequency Coverage: 0.5 kHz – 1.750 GHz
    • HF: 0.5 kHz – 31 MHz
    • VHF-I: 31 – 66 MHz
    • VHF-II: 66 – 118 MHz
    • VHF-III: 118 – 260MHz
    • UHF: 260 – 1750 MHz
  • Sensitivity (MDS @ 500 Hz BW)
    • HF: -141.0 dBm Typ.
    • VHF/UHF: -142.5 dBm Typ.
  • Linearity (at maximum gain)
    • HF: +15 dBm IIP3
    • VHF: +5 dBm IIP3
    • UHF: 0 dBm IIP3
  • Blocking Dynamic Range (BDR)
    • HF: 110 dB
    • VHF/UHF: 95 dB
  • Reciprocal Mixing Dynamic Range (RMDR)
    • HF: 89 dB at 20 kHz separation
    • VHF: 82 dB at 50 kHz separation
    • UHF: 74 dB at 50 kHz separation
  • Input Impedance
    • VHF/UHF: 50 ohms
    • VLF/LF/HF: 1k ohms
  • Selectivity
    • RF Preselectors
    • Polyphase Harmonic Rejection Mixer
    • IF Filters
    • Sigma Delta Modulator
    • DDC
  • Image Rejection
    • HF/FM: 120 dB (Zero-IF)
    • VHF/UHF: 75+ dB (Low-IF)
  • Architecture
    • HF/FM Broadcast: Direct Conversion (Harmonic Rejection Zero-IF)
    • VHF/UHF: Double-Conversion (RF to Low-IF to Zero-IF)
  • RF Filtering
    • HF: 5 Preselection Filters
    • VHF/UHF: 5 Preselection Filters
  • Gain Control
    • Smart AGC with real time optimization of the gain distribution
    • User controlled Attenuators with 4 dB steps and 0 – 28 dB range
  • Bias-Tee
    • User controllable for HF and VHF/UHF
    • HF Bias-Tee bypass switch for the best VLF sensitivity
  • Connectors
    • HF: SMA (+15 dBm Max)
    • VHF/UHF: SMA (+15 dBm Max)
    • Clock: MCX (10 MHz)
    • USB: Type C
  • ESD/RF protection with double BAV99 and fast TVS diodes in the RF ports
  • ESD protection with USB TVS chip in the USB port
  • Up to 710 kHz alias and image free output for 912 KSPS IQ
  • High Dynamic Range HF/IF circuit based on 2 x Sigma Delta ADCs @ 36 MSPS followed by a Digital Down Converter (18-bit DDC) and controlled by the Core AGC
  • 5 ppm high stability, low phase noise VC-TCXO with software-controlled DAC
  • Low phase noise PLL (-110 dBc/Hz @ 1kHz separation @ 100 MHz)
  • No drivers required – 100% Plug-and-play on Windows 10 and 11. Open-source user mode driver for Linux and other platforms.
  • Operating Temperature: -20°C to +48°C
  • Ultra small Form Factor with RF tight CNC enclosure

Typical Applications

  • SIGINT/COMINT
  • Radio Monitoring
  • HF/VHF/UHF Telemetry
  • Ham Radio (HF, 6m + 2m, 70cm, 23cm)
  • Short Wave Listening (SWL)
  • AM/FM/TV DX
  • Long Range IoT

Supported Software

Supported Operating Systems

  • Windows 10 and 11
  • Linux
  • *BSD
  • Mac

Supported Hardware

  • Intel compatible PC
  • Raspberry Pi
  • Odroid
  • 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

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