Tagged: flightaware

An Inside Look into FlightAware’s RTL-SDR

Over on the FlightAware blog, Hardware and Software Engineers Eric Tran and Ziquan Wang have put up a blog post showing how they have designed the FlightAware RTL-SDR hardware and software, and detail some future plans.

FlightAware is a company that specializes in distributed ADS-B aggregation, in order to produce real time maps and information about what aircraft are in the air. In 2021 FlightAware was acquired by Collins Aerospace, which is a subsidiary of Raytheon Technologies, a large US aerospace and defense contractor.

Most of the data that FlightAware obtains comes from volunteers all around the world running an RTL-SDR dongles on their Raspberry Pi based image. The dongles receive the ADS-B 1090 MHz broadcasts from aircraft which contain information about the aircraft including GPS location. 

Back in 2016 they released the FlightAware ProStick, which is an ADS-B optimized RTL-SDR with onboard 1090 MHz LNA.  Later in 2017 they released the Prostick Plus which improved performance in high interference areas due to the addition of a 1090 MHz SAW filter.

Their post goes into more detail about their products, and note that they are currently designing a new Prostick Plus with filter placed before the LNA instead of after. They also discuss how they are looking into higher end 12-bit ADCs for their receiver hardware, and at creating a dual channel receiver for the 978 MHz UAT band as well. They then go on to discuss the software architecture behind the ADS-B decoder they use.

FlightAware ADS-B Kitset

Measuring the USB Power Consumption of Various Software Defined Radios

Over on his YouTube channel icholakov has uploaded a video comparing the USB power consumption of various software defined radios. In his tests he uses an inline USB current meter and compares a Perseus, RSP1, RSP1A, Airspy HF+, Airspy HF+ Discovery, RTL V3, Nooelec RTL Mini, Hauppauge 955Q, Flightaware RTL.

If you're only interested in the summary table, then this can be found at 05:49 in the video.

Generally SDRs with better performing tuners and more amplifiers will have higher power requirements, although current consumption can't solely be used to judge performance as some SDRs like the SDRplay make extensive use of filtering to overcome RX performance issues in their tuner. The RTL-SDR V3 and FlightAware dongles have slightly higher current draw compared to the Mini RTL-SDR as they contain an additional HF amplifier and ADS-B amplifier respectively. Lower power consumption may be useful when used with batteries and mobile phones.

2019: Nine SDR Receivers power consumption comparison - how much power does your SDR consume?

Getting the V3 Bias Tee to Activate on PiAware ADS-B Images

A few owners of our RTL-SDR V3 and/or our Triple Filtered ADS-B LNA (or other bias tee powered LNAs) have been having trouble getting the V3 bias tee to activate on the FlightAware PiAware Raspberry Pi image. The core stumbling point is that the PiAware image activates the dump1090 ADS-B decoder immediately upon boot. To activate the bias tee, the bias tee software requires access to the dongle which it cannot get since dump1090 is blocking it. So to get around this the bias tee must be activated first before dump1090 runs.

PiAware is FlightAware's Raspberry Pi image which feeds their flightaware.com flight tracking service using RTL-SDR dongles. By using our Triple Filtered ADS-B LNA, users can expect increased range and decoded messages, especially when using long runs of coax cable, and/or in environments with strong interfering signals.

In the instructions below we'll explain how to set up a PiAware image that automatically enables the Bias Tee upon boot.

Downloading the V3 Bias Tee Software onto PiAware

First we assume that you're starting fresh from a new PiAware image, so we need to enable WiFi and SSH connections which is part of the standard set up for PiAware. See the following links for instructions.

Enable WiFi via config file https://flightaware.com/adsb/piaware/build

Enable SSH by adding ssh file to boot https://flightaware.com/adsb/piaware/build/optional#password

Now log in to your PiAware machine using SSH and PuTTY (or any other terminal software) using username "pi" and password "flightaware".

Run the following commands to update and install some dependencies. 

sudo apt-get update
sudo apt-get install git cmake build-essential libusb-1.0-0-dev

Download and install the RTL-SDR V3 Bias Tee software.

cd ~
git clone https://github.com/rtlsdrblog/rtl_biast
cd rtl_biast
mkdir build
cd build

Testing the Bias Tee

Over on his blog Akos has created a short guide to activating the bias tee manually, by first stopping dump1090, activating the bias tee, then restarting dump1090. It's a simple one line copy and paste job.

So after installing the rtl_biast software above you can use the following line to test the bias tee. After running this line the FlightAware service should be up and running again, with the bias tee and LNA activated.

sudo service dump1090-fa stop && cd ~/rtl_biast/build/src && ./rtl_biast -b 1 && sudo service dump1090-fa start

Automatically Starting the Bias Tee on Boot

Ideally we don't want to have to reactivate the bias tee manually every time the Raspberry Pi reboots. To make it automatic use the following instructions:

First create a service directory and configuration file

sudo mkdir /etc/systemd/system/dump1090-fa.service.d
sudo nano /etc/systemd/system/dump1090-fa.service.d/bias-t.conf

Then paste in the following

ExecStartPre=/home/pi/rtl_biast/build/src/rtl_biast -b 1

Finally press Ctrl+X then Y to close and save. Now whenever PiAware reboots the bias tee should be automatically activated as this service runs before dump1090 is activated.


Thanks to the discussion on the FlightAware forums and in particular user 'obj' for originally finding this automatic solution.

A Tutorial on Using a Raspberry Pi Zero Wireless for ADS-B Flight Tracking

Allaboutcircuits.com contributing writer Mark Hughes has recently posted a tutorial that shows how to use an RTL-SDR dongle with a Raspberry Pi Zero Wireless to track aircraft with ADS-B. As a bonus he also shows how to program and wire up a 64×64 RGB matrix screen to display currently tracked flight numbers.

The Pi Zero is one of the cheapest single board computers available, costing only $5 USD, and the wireless model with WiFi connectivity only costs $10 USD. It is powerful enough with its 1 GHz CPU and 512 MB of RAM to run an RTL-SDR and run several non CPU intensive applications such as ADS-B decoding.

The tutorial starts from the beginning by installing a fresh Raspbian image onto the Pi Zero. He then goes on to show how to install the PiAware tracking and feeding software from flightaware.com. Later in the tutorial he also shows how to collect data straight from the flightaware.com API, and also how to build and control an RGB matrix which can display live flight numbers.

It also seems that FlightAware themselves have recently released PiAware 3.5, which now directly supports the Raspberry Pi Zero Wireless.

Track Overhead Flights with a Raspberry Pi Zero Wireless, a Software Defined Radio, and FlightAware

FlightAware Prostick Plus Now Available in our Store

The FlightAware ProStick Plus is an modified RTL-SDR designed specifically for ADS-B reception. Its main defining feature is that it has a built in low noise figure LNA, and a 1090 MHz SAW filter. The LNA reduces the noise figure of the RTL-SDR, improving ADS-B reception and thus increasing the number of messages received and the receivable range of aircraft. The SAW filter helps remove out of band signals which can cause the RTL-SDR to overload if they are particularly strong. The Prostick Plus also comes with a TCXO, and SMA connector.

If you are mainly interested in ADS-B reception, or are looking to set up an ADS-B station then the Prostick Plus is one of the best choices you can make. See our previous review here.

We are now reselling some of FlightAware’s Prostick Plus dongles in our store now. They cost $24.95 USD including free shipping worldwide. We intend to sell them mainly to customers outside of the USA, as FlightAware already sell them officially on Amazon, but we offer free shipping anywhere in the world.

Click here to visit our store

The Pro Stick Plus RTL-SDR based ADS-B Receiver from FlightAware.
The Pro Stick Plus RTL-SDR based ADS-B Receiver from FlightAware.

Radioforeveryone New Posts: PiAware Step-By-Step Guide and a Guide to Feeding Other ADS-B Aggregrators

Akos from the radioforeveryone.com blog has recently uploaded some new posts. The first post is a tutorial on setting up a PiAware server with an RTL-SDR. PiAware is the official ADS-B feeder software from FlightAware.com, which is a web service that provides real time tracking of aircraft. Most of the flight data comes from volunteers around the world running a PiAware server with an RTL-SDR, ADS-B antenna and Raspberry Pi. The installation is fairly simple, involves burning an SDcard with the PiAware image, setting up the WiFi and then seeing your receiver online on the PiAware website. From there you can then configure the device further.

In the second post Akos describes how to feed other tracking websites, e.g. not just FlightAware, but also similar sites like Planefinder.net and flightradar24.com. Akos has also mentioned that a single Raspberry Pi can be used to feed all three aggregators simultaneously.

FlightAware vs FlightRadar24 vs Planefinder Plots
FlightAware vs FlightRadar24 vs Planefinder Plots

RTLSDR4Everyone Four New Posts: FlightAware Pro Stick Plus Review, Avoid FlightAware Ripoffs, Review of two BCFM Filters, Getting Started with Outernet

Akos from the RTLSDR4Everyone blog has recently uploaded four new articles. The first article reviews the new FlightAware Prostick Plus. The Prostick Plus is an RTL-SDR dongle optimized for ADS-B reception. It contains a LNA and 1090 MHz filter on board the dongle. In his review Akos tests the FlightAware Prostick Plus and compares it against the regular Prostick with external filtering. His results show that the Prostick Plus gets 18.45% more position reports and 5.4% extra max range in his location. His second post continues with the Prostick topic and warns customers to look out for sellers reselling, or relisting the Prostick for much higher ripoff prices.

FlightAware Prostick vs Prostick Plus
FlightAware Prostick vs Prostick Plus

In his third post Akos reviews our RTL-SDR.com broadcast FM filter and compares it against another similar filter from another seller. His test results show that both filters can improve performace.

Two BCFM band stop filters tested by Akos.
Two BCFM band stop filters tested by Akos.

Finally in his fourth post Akos writes a tutorial on getting started with Outernet reception. He bought the full Outernet bundle which comes with a battery bank, CHIP single board computer, E4000 with bias tee RTL-SDR, LNA with filter and patch antenna. His post describes what each component is, then shows how to use them to receive Outernet. His results also seemed to show that our V3 dongle significantly outperformed the E4000 dongle at Outernet reception. The V3 received the Outernet signal with a SNR of 6.39 dB vs only 2.58 dB with the E4000.

Some Outernet Components
Some Outernet Components

FlightAware Release their Pro Stick Plus: An ADS-B Optimized RTL-SDR with LNA and 1090 MHz Filter Built in

Back in March of this year we posted about the release of the FlightAware “Pro Stick”. The Pro Stick is FlightAware’s ADS-B optimized RTL-SDR dongle. It uses a low noise figure LNA on the RF front end to reduce the system noise figure, thus improving the SNR at 1090 MHz. Because the added gain of the LNA can easily cause overload problems if there are other strong signals around, FlightAware recommend using one of their 1090 MHz ADS-B filters in front of the dongle to prevent overload.

FlightAware have just come out with the “Pro Stick Plus” which is the same as their Pro Stick, but now with the 1090 MHz filter built into the dongle itself. The Pro Stick Plus costs $20.95 USD on Amazon, which is a good deal cheaper than buying the standard Pro Stick ($16.95 USD) plus their ADS-B filter ($19.95 USD), which totals $36.90. Customers outside of the USA can purchase the Pro Stick Plus from seller WiFi Expert on eBay for $29.95 USD.

FlightAware.com is a company that specializes in live air travel tracking. Most of their data comes from volunteers running RTL-SDR ADS-B receivers.

The new Pro Stick Plus RTL-SDR based ADS-B Receiver from FlightAware.
The new Pro Stick Plus RTL-SDR based ADS-B Receiver from FlightAware.

Over on their forums and on Amazon, they announced the device and specs. They wrote:

FlightAware is excited to announce the next evolution of USB SDR sticks for ADS-B reception! The new Pro Stick Plus USB SDR builds on the popular Pro Stick by adding a built-in 1090 MHz bandpass filter. The built-in filter allows for increased performance and range of reception by 10-20% for installations where filtering is beneficial. Areas with moderate RF noise, as is typically experienced in most urban areas, generally benefit from filtering. By integrating the filter into the SDR stick, we are able to reduce the total cost by more than 40% when compared to buying a Pro Stick and an external filter.


  • Filter: 1,075 MHz to 1,105 MHz pass band with insertion loss of 2.3 dB; 30 dB attenuation on other frequencies
  • Amp: 19 dB Integrated Amplifier which can increase your ADS-B range 20-100% more compared to dongles from other vendors which can increase range 10-20% over a Pro Stick in environments where filtering is beneficial
  • Native SMA connector
  • Supported by PiAware
  • R820T2 RTL2832U chips
  • USB powered, 5V @ 300mA

Note that this dongle is only for ADS-B at 1090 MHz, and not for 978 MHz UAT signals, as the filter will cut that frequency out.

Back in April, we did a review of the original Pro Stick. We found its performance on ADS-B reception to be excellent, but only when a filter was used. The low NF LNA theoretically improves the SNR of ADS-B signals by about 7-8 dB, but in reality there is too much gain causing signal overload everywhere, thus making reception impossible without the filter. Rural environments may not need a filter, but in a typical urban or city environment strong FM/TV/GSM/etc signals are abundant and these signals easily overloaded the Pro Stick when no filtering was used. This new Pro Stick Plus dongle completely solves that problem at a low cost with its built in filter.

Remember that if you are using a run of coax cable between the LNA and RTL-SDR, then it is more optimal to use an external LNA, like the LNA4ALL. Only an external LNA mounted near the antenna can help overcome coax, connector, filter and other losses as well as reducing the system noise figure. The FlightAware dongles are the optimal solution when they are mounted as close to the antenna as possible. This is usually the case when running the FlightAware feeder software on a Raspberry Pi.

We hope to soon review the Pro Stick Plus, however we assume it will operate nearly identically to the Pro Stick + FlightAware ADS-B filter combination.