PilotAware provides the best situational awareness information. Read on to see what is available and how it is done.
The information provided includes significantly more traffic types detected than any other system….
… also advanced flight information services such as Weather RADAR, Individual flight tracking data for SAR, Airprox reporting and checking the fidelity of all EC devices.
How is this done and how do we ensure that PilotAware will continue to be at the forefront of innovation in situational awareness?
The answer to this is that PilotAware is a complete infrastructure and not just a simple point to point Electronic Conspicuity (EC) device.
Most EC devices, irrespective on what frequency they transmit, only use direct point-to-point transmission paths to detect other aircraft.
Direct transmission and detection is a simple well-used technique but direct detection has several weaknesses that must be overcome if, any system relying on it alone is to be reliable, have sufficient integrity and futureproof for advanced services.
As the diagram below shows, Direct Detection is when an aircraft, equipped with onboard electronic conspicuity, transmits its GPS position which is then picked up by other aircraft with a similar device.
This often leads to the mistaken conclusion that if all aircraft used the same device then everyone would be able to see everyone else and there would be perfect ‘see and be seen’ harmony for all. Unfortunately, this would not be the case. It is not that simple and the following paragraphs show why.
The main issues that have to be overcome when using Direct Detection on a single technology are;
· airframe signal blocking (obscuration),
· topographical signal blocking,
· frequency congestion when using older signal modulation techniques,
· single points of failure,
· different requirements for air-to-air and air-to-ground (ATC) situational awareness,
· different flight use cases such as gliding versus commercial aviation.
· interoperability between all systems including drones.
Direct Detection is therefore not the complete solution and it needs some help. However, with help, all of the above weaknesses can be overcome.
Naturally, like the others, PilotAware devices started with Direct Detection as its main transmission path. The following table shows what a PilotAware user will detect and display using this first simple stage of interoperability.
Even at this early stage, PilotAware was detecting more EC types than any other system as we included a 1090MHz receiver and intelligent software, to also detect Mode-C, Mode-S, ADSB and CAP1391 transmissions on the Aviation Band.
†At this early stage of development (2016), Mode-C and Mode-S transmissions were displayed as targets without a bearing as they don’t naturally transmit GPS coordinates. However, with 12,000+ aircraft in the UK transmitting Mode-C/S signals, detection of these devices was a significant improvement over nothing at all. This weakness was overcome with the introduction of the PilotAware ATOM GRID in 2018, as shown below.
The different European EC transmissions
To be able to detect and display aircraft that are transmitting on different frequencies a mediation, or translation service is required. This is done by the PilotAware infrastructure.
The European EC Types and the modulation techniques used are:
Why is there not just one system?
You may have heard of frequency congestion being a problem on the 1090MHz aviation frequency. This is because the aviation frequency band uses a very old (1930’s) transmission technique called pulse position modulation (PPM). This is susceptible to frequency congestion in areas of high traffic and its use must be prioritised for commercial aircraft to avoid the unacceptable cost of wholesale changeout onto a more efficient modern modulation technique.
To overcome this, more modern systems such as PilotAware, Flarm, and Fanet+ use the regulated but unlicensed Industrial, Scientific and Medical (ISM) band. This provides significantly greater opportunities to provide innovative solutions not practically available on the Aviation Band. It also relieves the pressure on the Aviation Band so it can be used effectively for Commercial Aviation.
The ISM band has been adopted by EASA who call it the SRD-860 Band. In the above EC types diagram, FSK refers to the more modern modulation technique used which does not suffer from frequency congestion and allows greater innovation. This allows systems to be developed to meet the various aviation use cases such as GA, gliders, UAVs etc.
PilotAware ATOM GRID.
The ATOM GRID was the first PilotAware technology introduced to detect all these other European EC transmissions and rebroadcast them on the SRD-860 Band so they can be detected by PilotAware users. The diagram below shows the 3 antennas of the ATOM station picking up all the EC transmissions and rebroadcasting them to PilotAware users, if they are not being picked up by Direct Detection.
The 1090MHz (ADSB, CAP1391, Modes-C/S) is the Aviation Band. Regulated and licenced.
Both (869.25MHz) and 868MHz (Flarm) are on the EASA 860 Band. Regulated but unlicensed.
This means that more innovation is possible when using the SRD-860 Band.
The diagram below shows how this universal detection of all transmitting aircraft is done.
The following table shows what a PilotAware user will detect and display on an Electronic Flight Bag, Smart Tablet or screen using the ATOM GRID mediation and rebroadcast service.
From the table, it can be seen that all Flarm, Fanet+ and OGN trackers will now be detected and shown on tablets connected to PilotAware devices when in range of at least one ATOM station.
In addition, using the ATOM GRID and information from 360 RADAR Ltd, all Mode-S transmissions are now appended with their latitude and longitude using PilotAware Mode-S/3D multilateration technology.
For GA Airframes in the UK, Direct Detection plus ATOM GRID Rebroadcasts provide detection of a possible 12,000+ Mode-S transmissions, 5000+ PilotAware transmissions, 4,000+ Flarm and Fanet + transmissions and 3000+ ADSB and CAP1391 transmissions.
†Mode-C-only transmissions remain as bearingless targets for the time being.
Multiple detection and Rebroadcast using The ATOM GRID
The following diagram shows how The ATOM GRID uniquely detects, translates and rebroadcasts signals from aircraft using Electronic Conspicuity devices other than PilotAware. So PilotAware users can see more aircraft than any other system with the lowest possible latency (delay) available.
However, the detection translation and mediation of all signals to provide interoperability is only part of the ATOM GRID story.
With 320+ ATOM stations located in the UK, in flight aircraft are detected by several (up to 10+) ATOM stations at the same time. This detection from multiple angles helps to minimise aircraft signal obscuration caused by poor installation or the use of badly positioned or designed carry-on equipment.
The amount of aircraft seen is increased because the range of detection is improved and detection is now not a direct function of the transmit power or the receiver sensitivity of the device in the the aircraft alone.
· The second path, for EC data, through the ATOM GRID provides data path redundancy not available to other systems.
· The overall integrity of the system is improved over Direct Detection only.
No other EC system does this.
The picture below shows a typical aircraft being detected by the ATOM GRID. The green vectors show the PilotAware transmission being picked up at the speed of light by individual stations. The ATOM station will of course pick up all EC devices whatever EC Type they use. These transmissions can be used individually or collectively to track each aircraft without loss.
This allows PilotAware to track aircraft at lower altitudes than traditional Primary and Secondary RADAR which is the backbone of most ATC services in Europe.
The following diagram shows some of the 300+ ATOM stations installed in the UK.
More ATOM stations are installed in Europe and the Network is growing by about 4 stations a week. If you want to install an ATOM station at your location please contact ATOM@pilotaware.com to learn how we will subsidise the installation and provide the best Situational Awareness Flight Information Display for you.
The ATOM GRID was game-changing but there was more innovation to come to overcome the remaining weaknesses of Direct Detection and indeed the ATOM GRID itself.
No EC RADAR device can see around corners, behind mountains or at very low levels without a little help. That's where the expression ‘Flying below the RADAR’ comes from. This help is now provided by PilotAware SKY-GRIDTM
In terms of making the complicated simple, the latest SKY-GRIDTM software provides ground station functionality to all aircraft flying with PilotAware. This is like having our own satellites looking down to see around corners, behind mountains or locate aircraft and drones flying at very low levels out of range of an ATOM GRID ground station network.
The following diagram shows how Sky-GRIDTM Data Relay provides functionality not available to any other EC system. SKY-GRIDTM is available now and contributing to the amount of aircraft seen by the PilotAware infrastructure.
In simple termsSKY-GRIDTM works like this
· The red PilotAware-equipped aircraft is in range of at least 1 ground station providing transmissions at the speed of light with little latency.
· The orange PilotAware aircraft (or drone) is not in range of any ground station. In this case blocked by the mountain.
· The red aircraft detects the orange aircraft and recognises that it is NOT connected to a ground station.
· The red aircraft relays the position of the orange aircraft to the ATOM ground station, also at the speed of light. The ATOM ground station communicates this to the PilotAware servers in the blink of an eye, so the location of the orange aircraft is not lost to Situational Awareness Flight Information Displays or the rest of the network.
· The red aircraft then relays the locations of all aircraft in the vicinity of the orange aircraft so the pilot of the orange aircraft can see what he would have seen if it had been connected to the GRID via the servers.
SKY-GRIDTM therefore, overcomes topographical obscuration, improves low-level situational awareness, provides further path redundancy, improves overall system integrity and further reduces single points of failure.
SKY-GRIDTM effectively provides ground station functionality to every PilotAware-equipped aircraft.
No other EC system does this.
Introduced in 2022 PilotAware iGRID enhances the PilotAware infrastructure further.
PilotAware iGRID adds a 4th data link to PilotAware devices to;
· Provide a higher bandwidth data path.
· Increase data path redundancy.
· Improve integrity.
· Further, reduces single points of failure.
PilotAware iGRID software links your PilotAware device to the PilotAware Servers via your mobile phone. Whilst the mobile phone network is not suitable on its own for reliable, accurate Electronic Conspicuity it is very good as a redundant link and for the transmission of flight information services.
Using time-stamped data, PilotAware iGRID can now be used for Enhanced Traffic, Weather RADAR, and other services such as software upgrades, license renewal, diagnostic and safety services in the future.
Implementing iGRID is simply achieved through the addition of a small WiFi dongle and downloading the latest iGRID Software.
Combining all technologies together.
In joining all these technologies together the PilotAware user really does see more aircraft at a greater accuracy than any other EC system available today. The powerful computers built into in every PilotAware device, in every ATOM Station and in the PilotAware servers provide the leading-edge technology that ensures that you get the latest traffic data from multiple sources no matter what EC technology is being used.
PilotAware Ltd continues to innovate at pace using all technologies available.
Until there is a common frequency(s) available that will meet the requirements of all aviation use cases, then interoperability between systems must be the answer.
We trust that this paper has shown that PilotAware is providing answers to interoperability now.
By interoperability, we mean that users should be allowed to choose the EC that suits their type of flying and not be constrained to any individual frequency as some would advocate.
If you are currently an ADSB-out user then you can have everything above by simply integrating an inexpensive PilotAware Rosetta or Rosetta Fx into your current system.
If you don’t have ADSB-out but are fortunate enough to have a TRIG or Funke transponder with extended squitter, by using PilotAware Rosetta you can convert your Mode-S transponder transponder to ADSB-out SIL=0, by linking them together with an inexpensive interface cable.
This will then enhance your EC to give;
· ADSB in and out, SIL=0
· PilotAware in and out,
· Flarm in
· Fanet+ in
· Mode-S/3D in
If you are currently a Flarm user then you can have everything above by simply integrating an inexpensive PilotAware Rosetta FX into your current system.
Rosetta Fx is a brand new development from PilotAware Ltd available in Q3 2023. Rosetta FX links in series with your existing Flarm unit to Provide PilotAware functionality.
Rosetta FX has most of the functionality of PilotAware Rosetta but has been developed specifically for Flarm operations.
Rosetta FX includes:
· Multiple power input options
· Plug and play with Flarm devices
· Remote Internal or external antenna options
· Internal or external GPS options
· Dedicated ADSB-in Chip
· Dedicated PilotAware in-out Radio
· Weighs 100 grams
· Low power consumption for long battery life.
· Additional sensors for future applications.
Installing a Rosetta Fx will then enhance your EC to give;
· Flarm in and out
· PilotAware in and out,
· Mode-S/3D in
EASA ADS-L Protocol Specification Enabled:
PilotAware FX is ready to be remotely updated for use with the EASA SRD860 frequency band as permitted pursuant to AMC1 SERA 6005C Point (a)(3). This will provide a common protocol for use in European U-Space-defined airspace.
In cooperation with other manufacturers, PilotAware has assisted EASA in the development of the ADS-L protocol and looks forward to helping the integration of GA aircraft with unmanned aircraft in Europe without unnecessary temporary or permanent airspace restrictions.
The SRD860 protocol is expected to be implemented by EASA in 2024. Rosetta and Rosetta FX will be ready.
Drones and UAVs.
In 2021 PilotAware Ltd in conjunction with the University of Central Lancashire UCLAN demonstrated autonomous BVLOS flight using the PilotAware infrastructure augmented with AI to avoid any aircraft with any EC. The submitted paper on this, "Towards mid-air collision-free trajectory for autonomous and pilot-controlled unmanned aerial vehicles" will soon be published and can be viewed on the IEE website.
PilotAware is developing Rosetta DX for UAV BVLOS applications available in Q3 2023. For more information please contact atom@pilotAware.com
Use with Confidence
We trust that this paper has shown that PilotAware is continuously innovating to produce the best Electronic Conspicuity and situational awareness products available in Europe.
The regulatory way forward may be clouded in uncertainty, but the PilotAware vision is clear: to provide the best products and services for GA aviation.
You can trust PilotAware!