ATM SURVEILLANCE
THE EVOLUTION OF NEXT
SURVEILLANCE TECHNOLOGY
According to ICAO’s Aviation System Block Upgrades program and other institutional plans,
the basis of this evolution is ADS-B supplemented by other systems.
Miguel Muñoz Martínez, ADS-B & multilateration product manager, SESAR CNS & Innovation, INDRA
ATM surveillance is evolving. New
challenges such as radio spectrum
use, separation reduction that leads
into increase of system performances and
cost reduction are factors that are driving
developments in surveillance systems. The
use of ADS-B supplemented and integrated
with other surveillance sensors will be the
basis of future surveillance, and INDRA is
working in SESAR for the development of
this new kind of technologies.
Composite surveillance
& Phase modulation
The evolution of ADS-B datalink and the
exchange of data between sensors and
composite surveillance improve sensor
performance. In particular, the use of
composite exploiting benefits of ADS-B
Mode-S information enhances the capacity,
integrity and security of both systems.
The composite systems provide additional
features that are not required for meeting the
minimum performance by each surveillance
data channel. Rather, the composite
provisions constitute supplemental system
capabilities that aim to provide benefit that
could be achieved by a system comprising of
both ADS-B and independent channels
within a single physical SUR Sensor system.
The objective of composite surveillance is
not to extend the coverage of independent
sensors i.e. by allowing ADS-B data to be
used as an in-fill to a missing WAM sensor or
to improve the continuity of a WAM
horizontal position track information by
filling in with ADS-B horizontal position
data. The benefits of a “composite” system
include: monitoring of ADS-B performance;
identifying “rogue” Version 0 / 1 ADS-B Out
installations; supporting the detection of
ADS-B avionics anomalies – spoofing, and
decreasing RF load.
INDRA validates the integrity of this
ADS-B information in what is called SMART
integration. Different kind of sensors, such as
multilateration and Mode S radars use the
validated ASD-B information in the track
management process, to enhance the quantity
and quality of data, and to reduce RF
pollution, while maintaining the
independency of the position determination
of this multilateration and Mode S sensors.
In the future, 2030 and Block 2 according
to ICAO ASBUs, old PPM modulation will be
replaced by Phase modulated signals that will
enable be the future ADS-B link. This will
multiply the capacity of the datalink several
times, allowing new content for messages to
be created and allowing new functions that
will increase performance and security in the
communications. INDRA is anticipating
already working in SESAR to analyse the
benefits of integrating these kind of signals
on its products.
ADS-B security
ADS-B is a cooperative and dependent
system. The system’s RF-interface and
modulation scheme is as vulnerable as any
other RF-based system. In addition to this,
target reports may be modified, created or
100 AIR TRAFFIC TECHNOLOGY INTERNATIONAL 2020
even suppressed in a relatively easy way.
Working together with a multilateration
system (composite surveillance) or
implementing new security functionalities,
the detection and report of different threats,
at sensor and at ground station level can
be achieved.
For its part, multilateration and Mode S
systems are more resilient than ADS-B, due
to the fact they use independent surveillance,
but they can be also candidates for threat or
spoofing. The passive multilateration mode
can be also be affected, because broadcasted
data can be sometimes different as the
downlinked. This information has to be
periodically validated, using composite
surveillance.
Indra is integrating these security
functionalities for ground surveillance
sensors: ADS-B, WAM and Mode S. The aim
is to detect at sensor level the potential
threats, and when possible report the
existence of them to system users.
Composite systems improve the security
level of isolate systems as well as create a new
composite data flow. ADS-B data – such as
position, identification or altitude
information – is validated using
multilateration, proving the resilience of the
composite surveillance.
Above: The IRTOS 4K video camera system, which produces
data that can enhance ATC system performance