For those signed up to emails, you’ll have probably already seen this, but if not, Pro Stick Gen 2 is currently in beta testing.
"If you’ve been waiting for a good excuse to give your PiAware installation a refresh, the time has come. The latest PiAware 11 SD card images are now available.
"The new images bring together the PiAware 11 software updates released a couple months ago (discussed in our June ADS-B newsletter) along with the newer Raspberry Pi OS Trixie. It also adds support for the Pro Stick Gen 2, our next-generation ADS-B SDR (software-defined radio) that is currently in beta testing and is not yet publicly available.
“Pro Stick Gen 2 uses a new SDR architecture as an alternative to the RTL-SDR design used by the current Pro Stick and is designed to deliver improved ADS-B reception and performance. We’ll have more information on it in future announcements as testing progresses.”
Very unlikely.
I don’t think the new chip has been announced, but @dvsvejk noticed support for the LPC4370, so it might be compatible with the HackRF One.
The R820T has been around since 2011, so it’s probably time for an update.
It’s basically a LPC4370 + R860T, similar idea to the Airspy Mini (i.e. use the LPC4370’s internal high-speed ADC and do the baseband work on the host). Not so much like a HackRF (the HackRF uses external ADCs, an analog I/Q path, and has transmit capability). There are different design decisions vs the Airspy on both the hardware & software side.
The host-side software provides a SoapySDR driver in addition to its own API, so you should be able to use the Gen 2 with any soapysdr client. This is actually how the 11.1 sdcard image provides dump1090/dump978 support for the Gen 2.
I see from the header file you linked, if the hardware is pg2sdr, then the xtal rate is 28.8 MHz. Is that then the sample rate over USB with 12-bits per sample?
I don’t know if what I’m about to say makes sense, but it’s something I’ve been wondering about: why not build an SDR along the lines of a Ubiquiti Bullet? It would plug directly into the antenna—eliminating coaxial cable and the associated signal loss—be weather-resistant, and include internal circuitry to convert the USB serial signal to Ethernet. From my perspective, this would be a huge leap forward: an antenna plus an external SDR with an Ethernet output, connected via a UTP cable to an RPi or PC installed indoors. I think that alone would make ADS-B setups extremely streamlined. However, regarding development, I have no way of estimating the costs involved in creating such technology…
I mention this because, about 15 years ago, we used wireless internet. Initially, providers used radios connected via coaxial cables—sometimes 10 meters or more of RG213 or even RG58—to 2.4 GHz omnidirectional antennas; at the customer’s home, a grid antenna with a coaxial cable and a PCI card was used to pick up the signal. Ubiquiti’s brilliant move was to eliminate coaxial cables and make the equipment outdoor-ready: this facilitates and simplifies installation while also reducing signal loss.
The problem is here.
The nature of SDR is the RF part (dongle in our case), just converts part of the RF spectrum to ‘noise’ on the USB. The ‘S’ in SDR is the software that resides on the Pi, PC etc. that demodulates the noise and turns it into data.
The ubiquiti has the entire radio up the mast, so what comes out is ‘real data’.
Your old gridpac or omni put RF down the coax to the radio at the bottom where the process of down converting and demodulation takes place.
If you like, you can mount your Pi in a waterproof box and mount it at or near the mast-head and feed with UTP or wifi. Adding PoE to UTP can simplify the install.
I understand your point of view. FlightAware itself has modified its SDR—specifically, the blue dongle. It is designed solely for ADS-B signals, unlike other SDRs that cover a wide frequency range. That is why I see no issue with manufacturing an SDR that not only features a specific (filtered) ADS-B band but also includes other specialized characteristics—such as an IP67-rated case, among other possible adaptations—tailored specifically for ADS-B use.
I don’t think it needs to be in a IP67 case, but it should be in a metal case – for heat dissipation and shielding.It’s a little disappointing that the current pro stick plus is in a plastic case.
The only thing that would need to withstand an outside environment is the LNA, since it should be near the antenna.
Sure - there is no technical reason it can’t be done, but ‘feature creep’ = ‘price creep’. (essentially, how much are you prepared to pay?)
My main point above is the (say) RTL dongle isn’t an SDR by it’s self. The ‘SDR’ is a combination of the dongle plus Pi/PC/etc. (eg. Flightfeeder) that actually does the demodulation into whatever mode you choose.
