Aircraft Light Communication

Project Information

ALC

Grant agreement ID: 737645

DOI

10.3030/737645

Project closed

EC signature date 20 December 2016

Start date 1 January 2017

End date 31 December 2021

Funded under

• SOCIETAL CHALLENGES - Smart, Green And Integrated Transport

Total cost

€ 1 451 812,86

EU contribution

€ 1 098 771,63

Coordinated by

FACTEM
France

Periodic Reporting for period 3 - ALC (Aircraft Light Communication)

Reporting period: 2020-01-01 to 2021-12-31

Summary of the context and overall objectives of the project

As part of a global effort to progress towards the “connected aircraft”, operators are deploying connectivity solutions on aircraft (A/C) to keep up with passengers’ demand while ensuring optimal A/C operational performance. Connectivity in the cockpit is crucial to support operations and related pilot decision-making. Most pilots are looking for performant wireless headsets as wired ones are known for causing pains (head, shoulder, back) and reducing mobility.

Current wireless connected devices in A/C are WiFi & Bluetooth. Although efficient, these have severe drawbacks such as security (hacking) and reliability (wireless networking signals are subject to interferences and complex propagation effects). LiFi communication is today the most promising candidate to overcome these drawbacks as it:
- Provides a secured mode of communication by transmitting data through a light beam,
- Guarantees no interference with other electronic devices.

ALC aimed to prove the concept of secured, performant and robust wireless connection based on light by designing and developing TRL5 ground tests prototypes for LiFi-enabled performant, robust & secure wireless communications means in the A/C. ALC needed to overcome three main challenges:
1) Reduce current consumption of the LiFi dongle to save battery & increase autonomy of connected devices, keeping the weight and size of devices in mind.
2) Improve connection robustness to comply with the severe environment of a cockpit. In an A/C, the luminous flux of the sun saturates photodiodes, while in the cockpit, the light is sometimes switched off, interrupting the connection. Abnormal conditions such as smoke could also render the communication inoperative.
3) Demonstrate data security to avoid any eavesdropping as well as attacks.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The 1st period consisted in specification work, with anticipated start of TRL4 prototype development for the audio headset, tablet and connected headset.
The 2nd period was focused on the achievement of TRL4 (lab test) for the audio headset and tablet, successfully validated by AIRBUS. It was also decided not to develop another application in WP4.
The 3rd period was marked by the achievement of TRL5 (cockpit test) late 2021 for the audio headset and tablet. The strong constraint of robustness to obstacles was overcome, and mobility could be efficiently demonstrated with an intrinsically secured connection.
COVID-19 seriously affected the project. A 6-month extension was approved by the JU to deal with its consequences. The technical challenge however was so high that TRL5 could not be fully achieved for WP3 - connected headset.
Main results are:

Audio headset:
o Successful demonstrator of 2 wireless headsets + 1 access point installed in an A350 cockpit simulator. Objectives in terms of mobility were met.
o Full duplex communication for up to 4 headsets with audio performances equivalent to a wired headset. Audio latency <2ms.

Tablet:
o Successful implementation of the LiFi tablet system towards both TRL4 & TRL5. Successful demonstration during review sessions and tests in A350 cockpit simulator with 2 LiFi enabled tablets + 1 access point. All TRL5 Criteria defined by AIRBUS were passed.
o Full duplex communication of the tablet system while showing significant improvement on system performance wrt resilience against obstacles, with the implementation of multiple transceiver concept.
o Simultaneous operation with the headset system, using the design and implementation on multi-user management.

Connected headset:
o TRL4 & TRL5 specification of a connected headset
o Prototype of aviation headset equipped with IMU, heart rate & presence sensors
o Graphical interface to display & recording of sensors data
o Optical communication protocol that sends physiological data along with audio data, with latency <2ms
o Full simulation model of optical propagation in the cockpit, with several parameters: number of users, mobility, presence of smoke, ambient noise linked to solar radiation
o Evaluation of latency on a IEEE802.11 compliant USRP radio set up with custom designed front end

Other applications:
o 149 ideas downselected to 28.
o Technical and financial evaluation of 5 pre-selected ideas
o Selection of one application by AIRBUS: “optical backbone”

LiFi technology in A/C evaluation:
o Good knowledge of LiFi communication standards through continuous monitoring
o Security assessment of LiFi applications in the cockpit
o Successful cross testing of LiFi headset & tablet in an A350 cockpit simulator
o Impact analysis of the introduction of LiFi technology in the A/C
o Performance and benefits/costs balance comparison of LiFi headset and tablet against other technologies
o LiFi certification recommendations, with drafts for new standards for LiFi-enabled headset and tablet

Management, dissemination and exploitation
o Day-to-day contractual management
o Several dissemination activities with global outreach: 1 PhD thesis, 2 articles, online webinar, participation to trade fairs, etc.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

ALC aimed to prove that LiFi connection can successfully replace radio waves for wireless communication in an A/C. ALC adapted existing LiFi technology to the demanding environment of a cockpit and A/C and worked around its current limitations.

Development of wireless connected devices and applications adapted to an A/C
- Audio headset: an autonomous LiFi wireless headset with low consumption and no extra weight, suppressing the need for wired connections in the cockpit.
- Electronic Flight Bag Tablet: a LiFi wireless tablet to allow flight crews to perform a variety of functions traditionally accomplished by using paper references (flight planning calculations, operations manual, etc.).
- Connected headset: integrating both audio connection and data transmission, beneficial for security aspects and to detect any pilot health issues.
ALC also investigated leads for future potential LiFi applications.

Improvement of operational performance
- Improved security: LiFi transmits data through a light beam, making impossible any attempt of hacking and/or external control taking.
- Improved reliability: LiFi is free of electromagnetic interference and guarantees no interference and perturbation with other electronic devices.
- Improved performance/efficiency: LiFi allows the use of a wide, unlicensed, free-to-use spectrum. As it is interference-free, LiFi can achieve about 1000 times the data density of Wi-Fi at very high data rates, with fewer components and negligible additional power.
- Improved mobility: Fully secured, reliable and high-performing wireless connectivity will remove the need for wired headsets for pilots and will allow crew members to use connected devices everywhere in the A/C.
- Affordable solution: More wireless LiFi connection means a reduction of electrical wiring, leading to less weight and fuel consumption, less harness fabrication complexity and the suppression of connector replacement costs.
- Suppression of health hazards: As LiFi relies on visible light, it will have no impact on the health of the crew and passengers compared to other wireless radiofrequency technologies (e.g. electromagnetic sensitivity). Wireless headsets will suppress the pilots’ pains and stress due to wired headset, which can be critical especially for operations where the safety margin is already low (e.g. take-off or landing operations).

LiFi headset and tablet final tests

Project logo