Wireless communication for improved workflow and additional

Wireless communication for improved workflow
and additional services in the aircraft cabin
Ralf God*1, Hartmut Hintze2
1
Hamburg University of Technology
Institute of Aircraft Cabin Systems, Nesspriel 5, D-21129 Hamburg
2
Hamburger Logistik Institut GmbH
RFID Laboratory, Bredowstraße 20, D-22113 Hamburg
* [email protected]
Abstract -- The use and continuous development of
information and communication technology is a crucial
point for the future of our information society. Topics such
as connectivity, mobility, broadband transmission, wireless
networks and use of portable electronic devices (PEDs) play
an increasingly important role in the passenger cabin of
commercial aircrafts. This paper deals with a range of
wireless technologies, such as contactless smart cards, radio
frequency identification (RFID) and near field communication (NFC). Their use by passengers, airline crew
members and maintenance staff can increase profitability
through more efficient workflow and additional services
within the aircraft cabin. Identification, detection and
sensing functionalities will be discussed in this paper. In the
future devices using these technologies could serve as
valuable wireless interfaces to connect people and objects to
further and even more sophisticated wireless sensor and
communication networks in the cabin.
Index terms – aircraft cabin, technology platform, smart
card, radio frequency identification (RFID), near field
communication (NFC).
I.
INTRODUCTION
The aircraft cabin and its equipment is the central
part of an air journey where an airline has to satisfy
all passenger needs during its main transportation
service. These efforts have to be in line with
efficient airline operations. The integration of enhanced communication network technologies could
support efficiency and passenger comfort.
In a requirements-driven approach for the use of
wireless communication networks and interfaces in
commercial airplanes the aircraft cabin can be
considered as a closed system environment with
three substantial interest groups: The aircraft
manufacturer, the airline and the travelling
passenger. However the motivations for these three
groups concerning the potential use of wireless
technologies in the cabin differ from each other:
- The aircraft manufacturer needs to simplify
customized cabin mounting, cabin reconfiguration
and maintenance procedures along with weight
reduction. He has to increase cabin network
performance and has to comply with the information security requirements in aviation.
- The airline needs to improve the existing cabin
workflow and logistics and needs to reduce crew
workload by extended communication and information capabilities.
- The passenger wants to use communication-,
information- and entertainment-services at reasonable cost and at highest performance. Seamless
connectivity at the airport and in the cabin is
desired for portable electronic devices (PEDs).
Passenger needs in the cabin mainly derive from
network infrastructures which are well-known from
ground applications. Yet, different information
security and certification requirements have to be
considered on board an aircraft.
With reference to the airline a further and even
more important aspect has to be addressed:
- The service interaction with the individual
passenger has to be improved and customer
relations management for additional revenue
generation and a constantly high customer loyalty
has to be strengthened.
Possible technology solutions which fulfill these
needs are typically derived from a careful
requirements analysis for the above mentioned
three interest groups and should not be triggered by
availability of a technology. In practice, however,
successful innovation is very often based on a
conflation of a demand pull and technology push.
Contactless smart card technology, RFID and
NFC are already in a widespread use on ground and
thus may be an enabler to satisfy many of the
requirements for a seamless infrastructure. When
combining these wireless interfaces with a selforganizing wireless communication network as
backbone, the flexibility and scalability of
applications in the cabin is even higher. For this
reason it is worth to look more deeply into this
platform composed of smart cards, RFID and NFC
and its potential use in a cabin environment.
After briefly introducing a wireless cabin
network backbone and the aircraft domains, this
paper focuses on contactless interfaces for people
and objects. In this context smart card, RFID and
NFC technology are highlighted to be a valuable
and useful sub-domain of a basic network. An
aircraft cabin scenario finally illustrates the
improved workflow of the crew and additional
services to passengers.
II. WIRELESS COMMUNICATION IN THE CABIN
A. WIRLESS NETWORK BACKBONE
Today's standard in the cabin is a wired network
backbone. Wireless interfaces to connect passenger
notebooks and mobile phones have currently been
developed and are already in use [1-3].
With respect to weight reduction, flexibility and
scalability, efforts are being made to use wireless
network architecture for cabin in-flight entertainment [4] and cabin management applications [5, 6].
Ideally such basic wireless network function could
derive from the low power characteristics of shortrange networks, which allows the use of large
bandwidth for transmissions. Furthermore the
network structure should support the selfconfiguration approach of an ad-hoc network with
its advantages of increased reliability due to
multiple connection paths (see Figure 1) and less
administration and configuration work. Offering
passenger service applications at the aircraft seat by
such wireless networks are very attractive options
for the future.
domain (ACD) has the highest level of criticality
and contains the flight and embedded control
functions and the cabin core sub-domains which
support safety critical services. The airline
information services domain (AISD) contains
among others the cabin-operation and maintenance
functions for the flight deck and the cabin. This
domain handles less critical information than the
ACD. At the lowest level are the passenger
information and entertainment services domain
(PIESD) and the passenger owned devices domain
(PODD) that support passenger entertainment and
productivity like e.g. onboard passenger web.
Fig. 2. Aircraft domain model and related functions and services.
All cabin functions and services described within
this paper are located within the AISD and PIESD
and are linked to some extend to the PODD.
C. VALUABLE WIRELESS INTERFACES IN THE
AIRCRAFT CABIN
Fig. 1. Schematic view of an in‐seat wireless cabin network backbone. Figure 1 illustrates how such a network could be
implemented within the aircraft cabin. A detailed
evaluation of the related aircraft certification issues
remains to be done and is not part of this paper.
B. AIRCRAFT DOMAINS
The aircraft domain model consists of four
domains as shown in Figure 2. The aircraft control
Services and logistic processes in the aircraft
cabin can be improved by automated and secure
identification of objects and people [7, 8]. There is
a high potential for smart card technology, radio
frequency identification (RFID) and near field
communication (NFC) to fulfill many of the
requirements given in the introduction. Including
sensing functions for objects and biometric
identification for people will even enhance possible
improvements. These wireless devices can lead to a
unique back end platform in the aircraft cabin,
interfacing with more sophisticated self-organizing
cabin communication networks which are under
development. Moreover it is expected that this
platform provides new auto-ID applications to
improve workflow and to offer additional services
in the cabin environment. It is important to note that
technology standards for this platform are deployed
worldwide and originally derive from secure and
wireless smart card payment systems.
Before illustrating beneficial use cases in the
cabin, the technology of modern auto-ID systems is
briefly described.
C.1 Radio frequency identification (RFID)
RFID systems are closely related to smart cards
(cf. subsequent paragraph B.2) and can be considered as the most simple electronic auto-ID
system. 1 Data are stored on a microchip which is
attached to an antenna. This resulting chip-antennaunit is called transponder, RFID label, smart label
or even just RFID tag.
A passive transponder withdrawing energy for
data storage and wireless data transfer from the
electromagnetic field of an actively transmitting
read/write unit, commonly called the RFID reader
or interrogator, is the easiest case. Due to the purely
passive role of these transponders there is basically
no violation of the EMC regulations of the EASA
or FAA certification agencies. 2
This situation is similar for semi-passive RFID
labels which use an internal power source (e.g. a
battery and/or an energy harvesting device) to
monitor environmental conditions (e.g. temperature,
humidity, shock) by sensing elements, but also
require radio frequency energy transferred from the
reader to power an RFID tag response.
Certification aspects are more critical when
continuously powered active labels are used. Active
tags do not rely on reader energy, but use an
internal power source to continuously power the tag
and its RF communication front end. Thus, active
RFID allows extremely low-level radio frequency
signals to be received by the tag and the tag
supported by the battery can generate high-level
signals back to the reader. Active RFID is typically
used, when a long read distance is desired.
For use in the aircraft cabin the frequencies of
readers and transponders need to be apart from the
aviation frequency bands to prevent interference
with other aircraft systems. Common RFID
frequencies in use (13.56 MHz, 860…960 MHz and
2.45 GHz) comply with this condition. The
standards for these systems are deployed world1
wide, which is another important prerequisite for
their use in the air transportation system.
C.2 Smart card technology
The two main categories of smart cards (or chip
cards) are memory cards and microprocessor cards.
An early application of memory cards with
storage components and security logic was their use
in payment for telephone applications. Memory
cards have become very cheap and can be used as
prepaid value cards or credit cards. An integrated
security function prevents from data forgery.
The early use of microprocessor cards was in
banking applications. They comprise of a storage
part and freely programmable microprocessor
components. Functionality and cost of these cards
are only defined by memory size and computational
power. The microprocessor part allows to run
cryptography algorithms and to store secret keys.
More recently, biometric identification procedures
have been introduced instead of using secret
alphanumeric passwords. Differently from a secret
password known by a person, in this latter case a
biometric feature of the person him- or herself
serves as the key.
Smart cards have typical form factors. Most well
known is the ID-1 (54.0 mm x 85.6 mm) format.
The ID-000 (15.0 x 25.0 mm with a 3.0 mm
truncated edge) format is predominantly used in
mobile tele-phone applications. It is worth to
mention that smart card functionality can also be
integrated e.g. into the housing of an USB stick and
then can be used as a token.
Modern smart cards use a contactless interface,
where energy and data transfer is performed
without galvanic contact of the card. Originally this
interface served as a model for the above described
RFID transponders. Therefore it is not surprising
that radio frequency standards and frequencies in
use are merely the same and thus are compatible
with the aviation frequency bands. Smart card
standards have been spread and accepted
worldwide. For the electronic passport (e-passport,
biometric passport), which uses contactless smart
card technology, standards were determined by the
International Civil Aviation Organization (ICAO). 3
The most known non-electronic auto-ID system is the barcode.
2
The European Aviation Safety Agency (EASA) and the Federal
Aviation Administration (FAA) in the United States provide specifications and regulations for certification. For example the testing of
emission of radio frequency energy is specified in the EUROCAE ED14 and RTCA DO-160 documents, describing environmental
conditions and test procedures for airborne equipment.
3
Cf. Machine Readable Travel Documents - ICAO Document
series 9303. In this document series ICAO refers to the ISO/IEC 14443
smart card standard (contactless integrated circuit cards).
C.3 Near field communication (NFC)
NFC is an extension of the ISO/IEC 14443
contactless smart card standard. 4 Contactless smart
card technology and smart card reader technology is
combined on a single device. Expectably personal
electronic devices (PEDs) such as mobile phones
with independent power supply are used as NFC
units.
Three communication modes result from an NFC
device: the smart card emulation mode, the
read/write and the peer-to-peer-mode. In the smart
card emulation mode the mobile device provides
functionality of a contactless smart card. The
read/write mode allows the device to act as an
RFID or smart card reader, communicating e.g.
with passive RFID transponders or contactless
smart cards. The peer-to-peer mode serves as an
NFC device link. It is only specified for operation
in-between NFC devices and allows a bi-directional
transmission of data. Even larger data volumes,
such as photos, files, etc. can be exchanged in this
mode. The power supply of the NFC device is
needed when the PED is operated in the read/write
or peer-to-peer mode.
Currently NFC is not as widely spread as smart
cards and smart labels. However, due to the use of
the same standards, it can be expected to be a
valuable extension of this technology platform.
NFC applications which derive from existing smart
card topics, e.g. ticketing in mass transport and
cashless payment, are already in use to some extent,
predominantly in Asia.
D. SCENARIO IN THE AIRCRAFT CABIN
The aircraft cabin is the workplace for the airline
cabin crew and the service environment for the
travelling passenger. It was designed and installed
accordingly by the aircraft manufacturer and it is
continuously checked and maintained within a
certified maintenance program for ensuring reliable
operation, even in emergencies. The aircraft cabin
as the most competitive factor in passenger aviation
has still today potential for improvements.
Procedures in the aircraft cabin aim for three
important areas: efficient, reliable and safe cabin
operations, services and comfort for the passenger
and after all the cabin maintenance. All three areas
finally focus on cost, mainly deriving from
expenditure of time and human labor.
4
The air interface and protocol for NFC ist standardized in
ISO/IEC 18092 and ECMA-340.
Wireless technology known from smart cards,
RFID and NFC in ground applications can
efficiently be exploited in the aircraft cabin. This
technology can be used in the cabin to comply with
requirements of the three stakeholders: airline,
passenger and aircraft manufacturer.
Fig. 3. Aircraft cabin procedures such as cabin operation, maintenance and passenger service can be supported and improved by wireless smart card, RIFD and NFC technology.
The subsequent paragraphs will illustrate how
workflow in existing procedures and processes can
be improved and how additional services can be
offered by using the above described technology
platform.
D.1 Cabin operation
Commonly the cabin crew is known by the variety
of services offered to the passenger during a flight.
However, the priority above customer service is to
meet the requirements for a safe operation of the
passenger cabin. In air transportation these precautions are of higher priority than those in other
mass transportation systems. Therefore many of the
flight attendant operations in the cabin are regulated
by the authorities.
At flight attendant positions an interface to the
cabin core system is available, providing access to
the cockpit crew, the aircraft, the maintenance staff
and the passengers. These functions are accessed
through the flight attendant panel (FAP) and the
cabin interphone. These elements are used for
communication, monitoring the cabin as well as
controlling and programming various functionalities. Several of these positions are distributed
throughout the aircraft to guarantee comprehensive
operation of the cabin from different positions. Due
to the overall criticality this interface it is secured
against unauthorized use.
devices offer additional possibilities for active
communication in the reader- or peer-to-peer-mode.
Downloading travel information, uploading
messages or pictures, or even ordering coffee or
snacks via PED applications is imaginable.
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Fig. 4. Cabin operations such as communication, monitoring, control and programming are handled via the flight attendant panel (FAP) and cabin interphone.
In the future a reader in the FAP for contactless
smart cards could help to further optimize existing
measures for preventing unauthorized use. Using
biometrics as login and assigning specific roles to
operators offers the advantage that a role can be
directly attributed to a staff member and her or his
individual biometric feature.
At this point, it should be recalled that biometric
identification of people will not be commonly
accepted. On the other hand it is important to
mention that biometric identification contributes to
secure and automated procedures and processes
where people are involved. Certain groups of
people, e.g. the crew, are already obliged to identify
themselves when doing their job. For these groups
new electronic ID documents can be regarded as an
improvement. In the travelers environment such
biometric ID documents can only be used on a
volunteer basis, e.g. for secured internet ticketing
and cashless payment, automated check-in and
electronic boarding.
D.2 Passenger service and comfort
The prospective use of this technology platform
at the passenger seat is very promising. For this
application NFC and smart cards are predominantly
of interest. The smart cards represent a classical
interface whereas NFC emulates this technology on
modern PEDs. In contrast to the purely passive
acting smart cards these PEDs can also take over an
active role in the information and communication
system.
At the aircraft seat smart cards or NFC devices
can be used for individual service interaction with
the passenger. Redeeming a voucher, earning or
spending bonus points within loyalty programs as
well as secure payment for specific airline services
is possible with contactless smart cards. NFC
Fig. 5. Individual airline/passenger service interaction by wireless devices at aircraft seat.
In the simplest case a wireless interface consists
of a smart card and/or NFC reader in the seat which
transfers data to the hardwired network domains. A
more advanced approach would interface to a more
sophisticated self-organizing wireless network
backbone in the cabin. This leads to reduced wiring
efforts and an easy reconfiguration of the seating
groups. In the future it is imaginable that displayand keyboard functionality is completely removed
from the seat and transferred to a PED application.
Possibly an NFC seat box then interfaces with a
wireless network and harvests energy for its lowpower operation directly from the passenger seat.
D.3 Cabin maintenance and safety related issues
The standard operating procedures (SOPs) for the
cabin crew are given in the cabin crew operating
manual (CCOM). In order to meet airworthiness
requirements for the cabin quite a number of the so
called preflight procedures are mandatory, others
are recommended. For example the checking of
emergency equipment is mandatory, whereas the
checking of the galley catering and the functionality
of the first and business class seats is optional.
For many of the safety related cabin crew tasks as
well as for cabin maintenance a wireless passive
RFID interface has advantages if a part or appliance
is difficult to access or has no electrical connection
to the cabin network domains.
The dimensions of the cabin and cargo hold and
the materials used inside basically represent an
environment which is feasible for the use of RFID.
Therefore checking of emergency equipment,
galley catering and first- and business class seat
operation can be supported with a handheld reader
for the crew. The presence and expiry date of life
vests, medical and survival kits can be indicated
and communicated without line of sight.
O2
elements are already proven in ground applications
and relevant standards are deployed worldwide. The
extension of communication interfaces into the
aircraft cabin would provide seamless connectivity
for passengers and the crew. The technology offers
well understood security features which are
triggered by continuously developing banking
standards and sovereign regulations for personal
identification.
IV. REFERENCES
[1]
[2]
[3]
Fig. 6. Use of wireless RFID interfaces for safety equipment and maintenance checks. Moreover RFID labels can be used as an
electronic seal to indicate tampering of compartments or containers. This sealing function can
be useful in cabin security search procedures.
Only in those cases, where an item seems to be
missing, expired or tampered, a more careful
inspection is required by the crew. Compared to
manual or visual inspection procedures, this
approach is more efficient and the passively acting
RFID interfaces comply with current regulations.
Another valuable feature for the maintenance is
the data logging capability of novel semi-passive
labels which do also comply with current
regulations. They can be used on equipment to
sense and log environmental data. Energy for the
sensing elements can be provided by foil-type
batteries even in combination with energy
harvesting devices.
Active RFID devices with a long read-range and
in combination with fixed reader installations could
be an option for the future, but today active RFID
does not comply with the authorities regulations.
III. CONCLUSION
In the aircraft cabin we consider a wireless
technology platform composed of RFID-, smart
card- and NFC interfaces as a unique human
machine interface (HMI) for the improvement of
processes where objects or people are involved. It
can be used in a passive, semi-passive or active
communication mode and serves as a platform
solution for all stakeholders: the airline, the aircraft
manufacturer and the travelling passenger. The
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