AAI Cover Page - PowerPoint PPT Presentation

Loading...

PPT – AAI Cover Page PowerPoint presentation | free to download - id: 41f2e3-YzEzM



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

AAI Cover Page

Description:

... Can be used for Marine VHF / UHF Communication Can be used in HF Communication Airports Authority of India ... Congestion of available ... solution is critical ... – PowerPoint PPT presentation

Number of Views:119
Avg rating:3.0/5.0
Slides: 37
Provided by: VIK15
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: AAI Cover Page


1
NEW TRENDS IN AERONAUTICAL AIR - GROUND
COMMUNICATION
2
  • AERONAUTICAL COMMUNICATIONS
  • Encompass all the facets of Ground Air
    Communications
  • The Communication Navigation scene is changing
    fast
  • Introduction of Satellite, VOIP ATM systems
  • The most vital is Air - Ground Communications
    between Aircraft
  • Pilot and Ground - based Air Traffic
    Controllers (ATC)
  • Our present talk is on advances in pilot - ATC
    Communications

3
  • AIR TRAFFIC CONTROL
  • Service provided by ground - based controllers
  • Prevent aircrafts from coming too close to each
    other
  • Ensures orderly and expeditious flow of traffic
  • Provides information to pilots, such as weather
    and
  • navigation information

4
  • CONVENTIONAL ATC SYSTEM
  • Predominantly voice - based
  • Analogue modulation for Voice TX/ RX
  • The communication clarity is prone to language
    ambiguities
  • The TX/ RX use channel spacing of 25 kHz - large
    figure
  • - difficulty in accommodating more frequencies

5
  • HANDICAPS OF THE CONVENTIONAL ATC SYSTEM
  • Congestion of available frequency spectrum ( 118
    - 137 MHz)
  • due to rapid increase in traffic demand for
    more
  • frequencies
  • Increase in no. of frequencies leads to small
    frequency
  • separation (lt 1.0 MHz Typ.). This causes
    interference
  • between different frequencies
  • May lead to error by ATC controllers who may
    hear more
  • than one voice at a time/ frequency

  • (Contd..)

6
  • It is estimated that available spectrum will be
    saturated by 2011
  • Aircraft take-off/ landing delays
  • Compromise in the safety of passengers and
    flight crew
  • No common time base between Ground Air
  • Aircraft position known only to ATC

7
  • WHAT IMPROVEMENTS CAN BE DONE?
  • We must be able to reduce channel spacing of 25
    kHz
  • to accommodate more channels
  • Pilot should be provided with communication/
    navigation
  • data on data links
  • Data linking solution is critical - Free the
    pilot from using
  • voice as much as possible
  • VHF DATA LINK (VDL) technology should be
    implemented
  • to provide effective and reliable
    communications
  • (Contd...)

8
  • ICAO ( International Civil Aviation
    Organisation) FAA
  • (Federal Aviation Agency), USA Plan to deploy
    digital
  • Next Generation Communication (NEXCOM )
    program for
  • digital voice and data
  • Data link standard for these radios is VDL 2,3
    4 Mode.
  • NEXCOM stress is on VDL 3
  • System is capable of reorganizing transfer
    queues
  • NEXCOM project will be completed by 2020 in
    phases.
  • Trial already underway in some sectors in USA
    Europe

9
  • VDL Modes
  • VDL 2
  • Data only
  • one channel
  • VDL 3
  • Both Voice and Data
  • Four channels
  • VDL 4
  • Data only
  • Allows aircraft localization accurately not only
    to
  • controllers but also other authorized
    personnel

10
  • What are the options available to us?
  • Improvement in available spectrum utilization
  • European countries are utilizing 8.33 kHz
    channel spacing
  • Data instead of voice communication
  • Voice Communication in digital form

11
(No Transcript)
12
Typical VDL 2 Controller Pilot Data Link
Communications (CPDLC) Architecture
VDR Transceiver
FAA
VDL-2 Ground Stations
Router
HID
NAS LAN
NADIN II
Service Provider
A/G ATN Router
G/G ATN Router
NADIN II
13
  • What is VDL 3?
  • Based on D8PSK modulation
  • Utilize TDMA scheme ( different time slots in 1
    channel)
  • Provide both digital voice and data
  • Provide many options

14
  • Why VDL 3 for NEXCOM?
  • VDL 3 utilizes available spectrum more
    efficiently
  • Each 25 kHz channel consist of 4 voice/ data
    channels
  • Voice and Data available on same frequency
  • Voice and Data are in digital form
  • Ground station may also be controlled in VDL 3
  • ( Contd....)

15
  • VDL 3 provides various options for voice/ data
    transmission
  • VDL 3 increases the capability of VDL 2. In
    place of
  • 1 digital data channel in VDL 2, 4 digital
    voice/ data
  • channels are available in VDL 3
  • In VDL 3 Time Division Multiple Access (TDMA)
  • scheme is utilized

16
  • VDL 3 (Diagrammatic representation)

011
010
001
9.524 micro second (10.5 kHz)
101
110
111
001
45
000
101
Information Data Stream
100
110
100
Vector Phase Diagram
( Contd...)
17
  • Utilizes D8PSK modulation technique
  • Data component is in direct phase which moves
    from
  • one signal to another and on change of every
    45 degree,
  • it represent different bits of data
  • 31.5 kbps data rate
  • Modulation technique used is similar to the one
    used
  • in VDL Mode 2

18
  • VDL 3 (TDMA structure)

120 milliseconds
Slot A
Slot B
Slot C
Slot D
M sub-channel
V/ D Sub- channel
30 milliseconds
( Contd...)
19
  • Every slot is an independent Voice/ Data channel
  • Management (M) channel, controls all other
    channels
  • Voice/ Data ( V/ D) consists of Digitized Voice
    or
  • digital data ( 4.8 kbps rate )

20
  • VDL 3 (Slot structure)

Data 576 bits
PG Band 2.71 ms
V/ D Sub- channel burst
30 milliseconds
Aircraft Transmission
System Data 96 bits
Data 576 bits
V/ D Sub- channel burst
M sub channel burst
21.8 milliseconds
Ground Transmission
( Contd...)
21
  • Management sub channel is transmitted from the
    ground
  • for voice circuits
  • Controls the system configuration
  • Controls transmission direction
  • Provides voice signal status

22
  • VDL 3 (System Configuration)
  • 4V - Four different voice stations
  • 2V2S - 2 different voice stations at 2 different
    places
  • 2V2D - 2 different stations with 1 voice and 1
    data slot
  • 3V1D - 1 common data channel for 3 different
    voice stations

23
  • VDL 3 (Operational advantages)
  • Airborne lockout is present during ground
    transmission
  • Ground control is present for Near
    simultaneous
  • airborne transmission
  • Simultaneous transmission is controlled from
    the ground
  • Protections are provided against microphone
    faults

( Contd...)
24
  • Superior squelch operation
  • Superior co-channel performance
  • Noises from amplitude modulation do not effect
    its operation

25
  • VDL 3 (Structural advantages)
  • Sufficient increase in available Voice and data
    channels
  • Provision of dedicated voice and data channel
    for a station
  • is available
  • Both voice and data circuit may be present in
    one Transceiver
  • for a station
  • Various options are available for communications
    links at
  • various places

( Contd...)
26
  • Switching from voice to data is easy
  • Communication channel is selected on its own
  • TDMA is not affected by aircraft movement

27
Communications Transition - Mobile
CY
97
03
04
05
06
07
08
09
10
11
12
13
14
15
02
01
00
99
98
NAS Modernization Phases
Phase 1
Phase 2
Phase 3
Step 1
Step 2
Step 3
Step 4
Mobile Comm Steps
VHF Radio -25 KHz
NEXCOM Radio - 25 KHz VHF AM (voice)
(voice)
ATC/AOC
NEXCOM Radios VDL Mode-3
Terrestrial
(voice and data)
VHF
Digital Link
VDL-Mode 2
(ACARS)
CPDLC Build 2
ATN-Compliant
Non-VHF communications

support advanced data link applications
Agency Mobile
FTS2001
HF Voice
SATCOM Voice
HF Data Link
ATC / AOC
(ARINC 622)
Oceanic
SAT and VHF Digital Link
HF and SATCOM
ATN Data Link
(with ARINC 622/FANS-1)
(not costed)
28
  • Other VDL Modes
  • VDL 2
  • Allows for data-only link
  • Based on D8PSK modulation
  • 25/ 8.33 kHz channel spacing
  • Operating at 31.5kbps
  • Physical media access is realized on Carrier
    Sense
  • Multiple Access (CSMA) scheme

29
  • VDL Mode 4
  • Allows operating data links onto a common shared
  • channel resource
  • Based on GFSK modulation
  • 25/ 8.33 kHz channel spacing
  • Operating at 19.2 kbps with a net link capacity
    of 14kbps

( Contd...)
30
  • Physical media access is realized on Self
    organizing
  • Time Division Multiple Access (TDMA) scheme
  • Each super frame composed of 4500 timeslots,
    whose
  • duration is 13.33 ms
  • Super Frame duration in all cases is 1 minute

31
(No Transcript)
32
(No Transcript)
33
  • Conclusion
  • We are facing crisis in Communication
    capability in Civil
  • aviation field
  • Importance of data communication will increase
    and we
  • need to do planning for it
  • Temporary solutions will not be able to remove
    crisis
  • Next generation Radios are required with VDL
    VOIP
  • capability. Already being manufactured by a few
    vendors
  • The transition from conventional to VDL ATC
    shall involve
  • large - scale infrastructure changes at the
    ground aircraft level

34
  • Other Applications of VDL technology
  • Can be used for Ground VHF / UHF Communication
  • Can be used for Marine VHF / UHF Communication
  • Can be used in HF Communication

35
  • Airports Authority of India (AAI) Project
  • Supply of 300 sets of VHF TX/ RX RCU
  • for Air Traffic Control
  • Project Value INR 24 Crores
  • Manufacturer M/s Selex Communications (OTE),
    Italy
  • Project Duration January 2003 - May 2005

36
THANK YOU
About PowerShow.com