New Airspy HF+

The following is a cut & paste of two emails in the SDR-Radio-com Yahoo! group this morning.

Airspy HF+
Preliminary specs:
RX range: 0 .. 30 MHz (HF) and 60 - 270 MHz (+)
Architecture: Hybrid (Direct conversion + DDC) using 2 x sigma delta ADC's @ 36MSPS
Front end: Tracking Filters (all bands), High Dynamic Range LNA's and Mixers
AGC: Smart AGC controlled by the DSP
DSP: CIC, CFIR and a final (programmable) channel FIR - 18bit resolution
Final bandwidth/resolution after DDC: 18bit @ 600kHz - Scaled and streamed as 16bit
Image rejection: better than 120dBc
Blocking DR: 108 dB
Separate HF and VHF RF inputs - with option to use one multiplexed input if desired
USB 2.0 with Plug and play - No drivers needed
The RF section resides inside a metal shield
Aluminium enclosure about 60 x 100 x 15 mm^3

2 x 36MSPS IQ (equivalent to direct sampling at 72 MSPS) gives roughly 36MHz of bandwidth, however the ADC's used are sigma-delta with intrinsic anti-alias filtering.
We start with 16bit IQ at 36MSPS then it is frequency translated and decimated to 744.192 ksps 18bit IQ with a bit more than 600 kHz bandwidth plus the digital filter roll off. Given the very nature of sigma delta ADC's, the pressure on the front-end filtering is relaxed and the tracking filters are even more effective.
The image rejection is performed using a newly designed algorithm that matches the performance of the hardware.
All the decimation number crunching happens in the device like in most high end DDC receivers, so we only need a small USB throughput in the end (~23Mbps), and the CPU usage in the PC is very low.
Performance wise, the result is comparable to things like Perseus, RFSPACE, Elad, etc. but with a more modern full CMOS sensitive front end and at a fraction of the price.

They really do love tossing out those specs, don't they?

"Preliminary Specs" means "this is what we hope to get but we haven't succeeded yet...."

Simon Brown of SDR Console has been hinting about this receiver for the last couple of weeks. I took his comments to mean he might have had one. Time will tell.

--
Mike

It's odd that they are focusing on limited features. The Airspy (Yay!... but where is HF?) Then the convertor appeared (Yay!... but where is the pass-though?) Then the Mini takes to the stage? (Yay!.. but what was the point?) and now the rumour of an HF/VHF only unit is leaked? The audience for that is even more limited.

Meanwhile... SDRplay are selling a DC to 2GHz, twin/triple input, all-in-one unit (in a metal box, if desired) and cheap.

One thing that history shows, is that niche functions are ultimately overtaken by cheaper general-purpose devices.

Of course, all of the Youssef haters [already see some in this thread] will talk about other cheaper options that provide more of this or more of that.

Fact is, for the price that any of the currently produced / past produced Airspys, there isn't anything else out on the market that could touch their performance on VHF/UHF. i'll stand by that statement forever.

I don't need to like Youssef [although I do] to like the products he comes out with.

I'm anxious to hear more about this.

Mike

I am also anxious to hear more about this, too. Although I'm extremely happy with my 2 SDRplays, I enjoy listening to radio, and if the Airspy HF+ allows me to do that, then great!

--
Mike