Airspy HF+ | Airspy
HF and VHF pocket SDR with high dynamic range front-end. Tunable RF filter and polyphase harmonic rejection mixer for low-IF ADC. Ideated in USA, year of introduction 2017.
Reference market : ham-radio
0.0090 ~ 31.0000 MHz 
60.0000 ~ 260.0000 MHz
|Modulation mode||CW / LSB / USB / AM / FM / WFM|
|Tuning step||1 Hz min|
|MDS (Minimum Detectable Signal)||
-140.0 dBm / 0.02 uV (15MHz, BW 500Hz)
-141.5 dBm (60-108MHz, BW 500Hz)
-142.5 dBm (118-136MHz, BW 500Hz)
-140.5 dBm (136-174MHz, BW 500Hz)
-140.0 dBm (174-260MHz, BW 500Hz)
|Selectivity||User-defined bandwidth (0.1dB typ passband ripple)|
|A/D conversion||Freq.||36 Msps|
110 dB (HF)
95 dB (VHF)
|IP3 (3rd order intercept point)||
+15 dBm (max gain, HF)
+13 dBm (max gain, VHF)
|Maximum RF input level||+10 dBm|
|Image rejection||120 dB (software level)|
|Frequency accuracy||± 0.5ppm|
|Memory||Unlimited memory channels|
SMA 50Ω connector (HF)
SMA 50Ω connector (VHF)
|Power supply||USB 5 VDC|
|I/Q out||660 KHz bandwidth|
|Mechanical and environmental data :|
|Operating temperature||from -45°C to +85°C|
|Dimensions||60 (W) x 13 (H) x 90 (D) mm|
 The HF input port is optimized for bands higher than 300kHz, a simple modification for VLF is possible
Airspy HF+ is a joint effort between Airspy and Itead Studio. As pocket SDR uses a very high dynamic range front-end, also brings more performance from passive mixers with an excellent polyphase harmonic rejection structure. With its strong signal handling capability the Airspy HF+ is the ideal companion for light portable operation. Two RF tuner; for HF the receiver achieves excellent performance by means of a low-loss preselection filter, high linearity LNA, high linearity tunable RF filter, and a mixer that rejects up to the 21st harmonic. 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; for VHF excellent FM performance is achieved by using optimized signal paths composed of band filters, high linearity LNA with a stepped AGC switchable in 3 dB-steps and fully controlled by the firmware running in the DSP. Extended VHF coverage is assured by a second Band-III tuner up to 260 MHz, but with reduced performance.
Airspy HF+ architecture on HF path
The analog to digital converter (ADC) is a 4th order multi-bit noise shaping topology, sampling rate is determined by a control algorithm running in the embedded DSP. This 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. Once the IF signal is digitalized, the 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. The DSP core also implement a flexible and acoustically pleasant noise reduction algorithms, applications range from high-fidelity hiss removal for broadcast Wide-FM signals to unburying weak SSB signals from the HF noise floor.
Other features :
Frequency adjustment capability. Up to 660 kHz alias and image free for 768 ksps IQ output. Four programmable GPIO. No drivers required, plug-and-play on Windows Vista, Seven, 8, 8.1 and 10, Linux, OSX. Supported hardware: PC, Raspberry-Pi 2 and 3, Odroid C1/2 and XU4, other single board computers (SBC). Fully open-source driver, multi-platform. You can easily customize the HF input with one of published modifications: shunting an input capacitor would get the full band available for VLF listening, a custom filter can also be inserted between the SMA and the tuner block, for example.
Airspy HF+ price :
We have collected for your convenience the Airspy HF+ sales prices and their trend over time. Of course offers, accessories, warranty terms and conditions can lead to different figures.
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