Presentación Ingeniería.

1. Multi-
Constellation
Dual-Frequency
GNSS
Jhonny Herman Criollo
Valencia
José Antonio Rodulfo Guío
Roberto Valero Andérez

2. 1. Introduction
• GNSS systems are currently an essential
part of our CNS infrastructure.
Specifically in aviation by 2020 all of our
European fleet will be equipped with
GPS receivers.
• GPS is no longer the only constellation
in the sky, countries and groups of
countries around the world are working
to improve and/or deploy their own
constellations such as GLONASS,
GALILEO and BeiDou.
• We can take develop receivers that can
take process signals from multiple
constellations and obtain even more
precision than before.

3. 2. Technical Capabilities of
MCDF GNSS
• Multi-constellation multi-band global
navigation satellite system (GNSS)
receivers can efficiently exploit the
advantages derived from the
modernization of existing GNSS
constellations, such as GPS and
GLONASS, as well as from the launch
of new ones like Galileo and BeiDou.
MCDF receivers.

4. Multiple frequencies.
• Corrects Ionospheric error.
• Noise and multipath mitigation capabilities thanks to the new
L5/ E5a wideband signals
• More immunity to unintentional interference.

5. Multiple constellations.
• Reduced signal acquisition time.
• Improved position and time accuracy.
• Reduction of problems caused by obstructions such as
buildings and foliage.
• Improved spatial distribution of visible satellites, resulting in
improved dilution of precision.
• More immunity to scintillation since even though severe
scintillation can disrupt signals from satellites in all
frequencies it doesn’t tend to affect wide areas of the
ionosphere simultaneously, rather it occurs in patches.

6. Advantages.
• What we can expect from using MCDF GNSS receivers is an
improved availability and continuity of service, making our
systems more robust against interruptions in service and
allowing us to maintain our required operational performance.
This will also open opportunities for us to extend our service
areas and enable advance applications.
• Overall, we will be gaining a more robust system against
unintentional sources of error and we will be optimizing our
existing network of navaids.

7. 3. Operational Benefits Assessment
We are going to develop the benefits
of MCDF in terms of safety, capacity,
cost effciency and environmentOperational Capabilities; 0,2
Safety; 0,2
Capacity; 0,2
Cost Efficiency; 0,2
Environment; 0,2
Benefits

8. Improvements in availability and
robustness.
• Mainly, the benefits
of using dual
frequency and multi
constellation can be
summarized in
reducing ionospheric
delays.

9. Improvements in continuity and
robustness.
• Suppressing the
effects of ionosphere
to the GNSS signal
allows to reduce
probabilities of losing
GNSS service.

10. Improvements in service coverage
area.
• With Multi-Constellation
Dual-Frequency GNSS
we aim to achieve a
coverage area up to
72N, which will include
almost all ECAC.

11. Improved performance.

12. Independent time reference system.
• As we know, ionospheric
delay can be reduced with
dual frequency systems,
and so the time error which
it produces.

13. 4. Summary of SESAR work

14. Actual scenario of GNSS
• Transition
• Need for collaboration

15. Increased robustness and ‘forward-fit’.
• Other useful systems
• Benefits? → Forward-
fit

16. Transition and scope of MCDF.
• Retro-compatibility
• Different users

17. MCDF GNSS transition is
determined to be:
o A solution for nowadays
problems.
o An upgrade for present systems.
o A modern system that fits in the
future ATM Plan.
5. Way Forward: A cost-
effective transition.

18. Some aspects must be
considered:
o It has “pros and cons”
o Just like between GPS and
Galileo
Strengths and Weaknesses.

19. • More people
interested means a
smoother transition
Future of GNSS.

20. 6. Recommendations
• GNSS mandates must be
harmonised and synchronised
between them.
• Future mandates have to group
all CNS requirements to be met
as soon as possible.