Tagged: ads-b

Contributing ADS-B Data to RadarBox with an RTL-SDR and Raspberry Pi

RadarBox.com is an ADS-B aggregator which is very similar to other aggregators like FlightAware.com and FlightRadar24.com. These services use ADS-B data provided from volunteers all around the world to create a live worldwide snapshot of current air traffic. The data is then used by airlines, airports, aerospace companies, as well as enthusiasts and regular people to track aircraft and estimate arrival times.

Typically contributors to these services use an RTL-SDR combined with a Raspberry Pi as the receiver. Some sites also use their own proprietary hardware, but they seem to be slowly falling out of favor as the RTL-SDR solution tends to be cheaper and more effective.

Over on their blog RadarBox have uploaded a new tutorial that shows how you can contribute to their service using an RTL-SDR, Raspberry Pi and their new RBFeeder client software. The set up procedure is very simple as they provide a script which downloads and installs the software automatically.

On their store they also sell an ADS-B antenna and 1090 MHz preamp which may be of interest to some ADS-B enthusiasts.

RadarBox Web Interface
RadarBox Web Interface

Low Power RTL-SDR ‘Stratux’ Dongles Now Available in our Store

Over on our store we now have a limited amount of “Low Power V2” RTL-SDR dongles available for sale for $16.95 USD incl. free international shipping. These are dongles that were produced for the Stratux project which aims to provide a very low cost ADS-B and UAT receiver for small airplane pilots. These Stratux kits typically consist of a Raspberry Pi, two nano RTL-SDR dongles, a GPS dongle and a Android or iOS tablet. The two RTL-SDR dongles receive both 1090 MHz ADS-B and 978 MHz UAT which are decoded on the Raspberry Pi. The Raspberry Pi then sends the decoded aircraft position and weather data to the tablet via WiFi which is running commercial navigation software.

A full Stratix setup including, Raspberry Pi, two RTL-SDR nano dongles, GPS module, fan, and 1090 + 978 MHz antennas.
A full Stratux setup including: Raspberry Pi, two RTL-SDR nano dongles, GPS module, fan, and 1090 + 978 MHz antennas.

One issue that Stratux users continually run into, is that the Raspberry Pi is sometimes unable to power two or more RTL-SDR dongles. When running a Pi with two RTL-SDR dongles, a GPS dongle, and cooling fan the total power draw is above 1A which can cause power supply problems and glitching. By using a low power RTL-SDR these problems can be avoided by keeping the total current draw under 1A.

The Low Power V2 Stratux RTL-SDR’s draw about 160-170 mA, whereas standard dongles draw about 260 mA, so that’s a saving of almost 100 mA. On battery power this current saving can mean a few hours more of operation. The Low Power RTL-SDR dongle achieves its lower current consumption by using a switch mode power supply instead of a linear regulator which is commonly used on most other RTL-SDR dongles. The trade off is that switch mode supplies are inherently RF noisy, so increased noise can be seen on the spectrum. Despite the increased noise, most applications like ADS-B are not significantly degraded. We have seen switch mode supplies used on some other RTL2832U dongles sold in the HDTV market as well. For example all the R828D based DVB-T2 dongles that we have seen use switch mode supplies as well, and also draw about 170 mA.

We think that these low power RTL-SDRs could be useful in other non-stratux related applications too. For example, they could be used on mobile Android devices. One of the key problems with Android usage is that RTL-SDR dongles tend to drain the battery quickly. They could also be used on solar and battery powered installations to help achieve longer run times. Or like with Stratux they could be used on a Raspberry Pi running other applications, to ensure that multiple dongles can be attached.

Currently we are selling these dongles for $16.95 USD with free international shipping included. Note that these dongles do not come with an enclosure (just a bare PCB), and they do not have a TCXO. Below is more information about these dongles.

Click here to visit our store

The Stratux Low Power V2 Dongle.
The Stratux Low Power V2 Dongle

Back in November 2016 we posted a review on the Low Power V1 dongles. Since then Chris (the man behind producing these dongles) has brought out the Low Power V2 models which improves upon V1 significantly. By switching to a 4-layer PCB the dongle is now much quieter in terms of RF noise produced from the switch mode power supply, and it also now runs significantly cooler. The dongle also now uses even less power and is more sensitive compared with V1.

Over on his Reddit post Chris compared his Low Power V2 dongle against the Low Power V1, a generic nano dongle and a NESDR Nano 2. In terms of noise plots, the generic nano dongle was the quietest, with the low power V2 dongle coming in second. Interestingly the NESDR Nano 2 was almost as noisy as the low power V1 dongle. The improvements on the low power V2 dongle make it usable on VHF now.

Noise Floor Comparisons between four Nano styled dongles.
Noise Floor Comparisons between four Nano styled dongles. NESDR Nano 2 (Blue), Generic Nano (Orange), Low Power V1 (Gray), Low Power V2 (Yellow).

In terms of heat produced and power used, the NESDR Nano 2 is the hottest and most power hungry, followed by the Generic Nano, the Low Power V1 and then the Low Power V2. For comparison the NESDR Nano 2 draws 1.362W of power, the generic nano 1.318W, the Low Power V1 1.003W, and the new Low Power V2 draws only 0.933W.

Thermal Camera Photos of  four Nano Dongles.
Thermal Camera Photos of four Nano Dongles.

Chris summarizes his results as follows:

  1. The NESDR Nano 2 loses in pretty much every aspect except for noise floor on VHF frequencies compared against the Low Power v1.
  2. You can see the effects of heat on the R820T2 above 1.4 GHz.
  3. The “Generic Nano” was always a great performer in terms of sensitivity.
  4. For ~0.8W (in a dual-band build) less power, the cost is 0.41 dB @ 1090 MHz and 0.64 dB @ 978 MHz (compared to the Generic Nano).

The Low Power V2 dongles appear to be a good improvement over the V1 models. They are useful for applications that need low power draw, for example powering multiple dongles on a Raspberry Pi and for use on battery and solar power. The trade off for low power consumption is increased RF noise, but with the Low Power V2 dongles the noise is not significant and interestingly even outperforms the NESDR Nano 2.

Setting up a FLARM Receiver with an RTL-SDR and Orange Pi Zero: Tracking Gliders and Helicopters

Most people already know about ADS-B aircraft tracking, but few know about FLARM (FLight AlaRM). FLARM is a low cost and low power consumption ADS-B alternative which is often used by small aircraft such as gliders and helicopters for collision avoidance. It is used all over the world, and is especially popular in Europe, however it is almost non-existent within the USA.

Back in 2014 we posted about FLARM reception with the RTL-SDR, and also about the Open Glider Network (OGN). The OGN is an online FLARM aggregator that is similar to sites like flightaware.com and flightradar24.com which aggregate ADS-B data.

More recently, Łukasz C. Jokiel has posted a tutorial on his blog that clearly shows how to set up an RTL-SDR and Raspberry Pi Zero based FLARM receiver for feeding the Open Glider Network

Łukasz’s tutorial uses an Orange Pi Zero which is a very cheap (~$7 USD) Raspberry Pi embedded computing device. He also uses an RTL-SDR dongle and an antenna tuned to the FLARM frequency of 868 MHz. The tutorial goes over the Linux commands for installing the decoder, calibrating the RTL-SDR and setting up the Open Glider Network feeder.

Remember that FLARM is typically 10-100 times weaker than ADS-B so a good tuned antenna is required, and the OGN recommend building (pdf) a collinear coax antenna tuned to 868 MHz.

A Commercial FLARM receiver.
A Commercial FLARM sender/receiver.

SDRplay RSP1 & RSP2 Now Support ADS-B Decoding on the Raspberry Pi 2 & 3

Over on the official SDRplay blog, head of marketing Jon has announced that the RSP1 & RSP2 is now compatible with their dump1090 ADS-B decoders for the Raspberry Pi 2 & 3. They write:

ADS-B for both RSP1 and RSP2 now available for the Raspberry Pi 2 & 3 – you can get the software from downloads – http://www.sdrplay.com/downloads

If you are an RSP2 user, make sure you use Antenna Port B.

The RSP2
The SDRplay RSP2


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.


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.

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

Radio For Everyone: Testing Several ADS-B Antennas Under $50

Over on his blog ‘Radio for Everyone’ Akos has shared results submitted to him by FlightAware forum user ‘Nitr0’ which compares several ADS-B antennas that cost under $50 USD. The antenna that we most recommend for ADS-B is the FlightAware antenna, but for European buyers there are also many lower cost alternatives available on eBay, most of which are made by fellow radio hobbyists or hams. The tests use the six antennas listed below, comparing each one against the ‘reference’ FlightAware antenna.

  1. The FlightAware Antenna – $45 USD
  2. A Bulgarian made antenna by LZ3RR – $31 USD + shipping
  3. A Slovakian made collinear antenna by stanislavpalo130 – $25 USD + shipping
  4. A Slovakian made 5/8 antenna by stanislavpalo130 – $24 USD
  5. RTL-SDR stock antenna – Included with generic RTL-SDRs
  6. A 3.5 dBi loaded whip – $3 to $15 USD

In summary the tests seem to show that nothing beats the FlightAware antenna, with the closest in performance being the Bulgarian made antenna. We should mention however, without knowing the real radiation patterns, SWR and various other factors it is hard to say which one will work best for everyone. Different locations/obstacles/mountings could mean that antennas with different designs and therefore radiation patterns work better than others. But it seems that the FlightAware antenna is the top performer in the common scenario of being able to mount the antenna on a roof with a good view of the horizon.

Two ADS-B antennas being tested by Akos.
Two ADS-B antennas being tested by Nitr0.

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