FLARM and ADS-B and PCAS Traffic Display on PC

On Friday, March 15, 2019 at 12:11:48 AM UTC-4, Paul Remde wrote:
In my note above I was talking about OGN Trackers. They are low-power transmitters that go in sailplanes. They are a lower-cost alternative to a PowerFLARM or ADS-B Out. Some examples are shown he
http://wiki.glidernet.org/ogn-tracker
PowerFLARM transmitters need F.C.C. approval in the USA, I would think OGN Trackers would also need F.C.C. approval. But I'm not an expert on such things.

Best Regards,
Paul Remde

On Thursday, March 14, 2019 at 10:20:06 PM UTC-5, wrote:
On Thursday, March 14, 2019 at 9:52:22 PM UTC-4, Darryl Ramm wrote:
Things seem to be getting a little confused here. FlightAware is a service that uses a distributed network of 1090ES ADS-B receivers and flight data sourced though some NAS operators/data service providers, some of their data products also include 1090ES ADS-B data from Aireon satellites (that service is still rolling out AFAIK).

There is really no such thing as a "FlightAware equipped" aircraft. FlightAware is ultimately just tracking 1090ES Out equipped aircraft and in some cases just aircraft equipped with a transponder via other NAS provided surveillance. There is no way for FlightAware to transmit data to FLARM equipped aircraft or visa versa. But combining those signals on a single display on the ground is just software, and for example what PowerFLARM (with the ADS-B Option) kinda already does... combining data for local FLARM and 1090ES Out equipped traffic.

BTW it was Aireon sourced 1090ES Out data that helped convince some of the regulators to ground the B737 Max.


On Thursday, March 14, 2019 at 3:07:14 PM UTC-7, Martin Gregorie wrote:
On Thu, 14 Mar 2019 14:04:15 -0700, Paul Remde wrote:

The posts recommending the use of OGN are very interesting. The
customer I'm working with is not interested in having the aircraft
positions available over the internet, but our soaring club is.

Getting our club members to invest in PowerFLARM units or ADS-B Out has
been tough. The OGN Trackers look like a nice, low-cost alternative.

OGN in its original form was just a network of software-defined receivers
running on RaspberryPis that picked up FLARM transmissions, and passed
the data from them over the Internet to a webserver. This is what you
connect to on order to see all FLARM-equipped gliders and aircraft in
range of the network of receivers.

Since then a similar network, FlightAware, has appeared. It works in a
similar way to FLARM but it not compatible with it, but links have been
set up so that its now possible to co-locate OGN and FlightAware ground
stations and cross-link them so that, IIRC, FLARM traffic is broadcast to
FlightAware equipped aircraft and vice versa.

However, since they are transmitters, wouldn't a radio license be
required? Also, wouldn't F.C.C. approval be needed for any devices?

AFAIK its still quite possible to operate a pure OGN network with all
ground stations in receive-only mode.

OGN is only practical because, although a typical FLARM system only has
an operating radius of 4-5 km, an OGN receiver with a decent, well-placed
antenna can track FLARM-equipped gliders over a much larger distance,
typically 30km or so.

Go he http://live.glidernet.org around midday in the UK or Europe
to see what the system looks like when gliders are operating. Or look at
NZ or Australia about 12 hours earlier/later.


--
Martin | martin at
Gregorie | gregorie dot org

Aren't there also low-cost "OGN Trackers" (mostly in gliders in Europe?) which transmit signals that ground stations collect and contribute to the OGN servers?

Also, in the USA currently, there is the option of using goTenna devices along with the GliderLink app. That's designed for peer-to-peer location awareness, but ground stations using goTenna devices could be set up, and they too could send data to OGN.

BTW all of these (other than ADS-B Out transmitters), AFAIK, transmit on frequencies (and at low powers) that do not require a license.

Those examples use radio chips that run at 868MHz, which is allowed in Europe AFAIK. In the US you'll need something in the +-915 MHz band. And you'll need a compatible receiver. I believe the FCC licensing is for the manufacturer, of the transmitter modules or any off-the-shelf device. Not for the end user, and probably not for a consultant that is helping the end user put the modules together.

The goTenna Mesh devices are small and self-contained and available off-the-shelf in the US for about $60 each (and presumably FCC approved). Seems like an easier solution than putting together a European-style OGN Tracker. The goTenna also transmits (short data bursts) at higher power (1 watt) and thus has a longer range than the devices that only transmit 25 mW or so (assuming similar antennas - the goTenna internal antenna is not an efficient one). In actual use (as reported by GliderLink users) air-to-air range is 20 miles or more. The goTenna can't do much on its own (no display nor controls), instead, it also contains a Bluetooth radio, and thus can pair with software running on a smartphone (such as GliderLink).

A good project for somebody would be to open up a goTenna, and connect a better antenna for use as a ground station (receiving only). This is legal because it won't be transmitting. (The software app would need to be modified to ensure that.) This has been done, but not in conjunction with GliderLink, rather as a relay station for ground-to-ground use, possibly illegally (if the antenna is "too good"). https://community.gotennamesh.com/t/...-nodes/275/233

All this is "thread drift" because it does not answer the original question of how to display "FLARM, ADS-B and PCAS traffic".