1.0 PROBLEM DEFINATION:

To convert the weather information (Text) into standard ATIS voice message by Text to

Speech conversion and simultaneous broadcast of voice and digital data. Recovery of voice is

done and data is displayed simultaneously in the cockpit

1.1WHAT THIS SYSTEM IS ALL ABOUT?

Automatic Terminal Information System, or ATIS, is a continuous broadcast of

recorded uncontrolled information in busier terminal (i.e. airport) areas. ATIS broadcasts contain

essential information, such as weather information, which runways are active, available

approaches, and any other information required by the pilots. Pilots usually listen to an available

ATIS broadcast and simultaneously can read same information displayed at cockpit if necessory

before contacting the local control tower, in order to reduce the controllers' workload and relieve

frequency congestion.

The weather data and recording is updated when there is a significant change in the

information, like a change in the air pressure. It is given a letter designation, from the Phonetic

Alphabet. When contacting the control tower or ground station, a pilot will indicate he/she has

"information" and the ATIS identification letter to let the controller know that the pilot is up to

date with all current information.

In its simplest form, the ATIS is a continuously played recording of a person reading the

message aloud. Because the message needs to be re-recorded at every update (which is several

times per hour at least), this is quite cumbersome. Most airports use a more automated system

using a speech synthesizer nowadays, where a computer voice speaks the message. Most systems

use a female voice, because female voices are often easier to understand when radio reception is

less than optimal. Some airports have separate ATIS broadcasts for arriving and departing

aircraft, each on its own frequency. This keeps the message brief. Many high-capacity airports

employ the use of Digital ATIS (or dATIS). dATIS is a transcribed, digitally transmitted version

of the ATIS audio broadcast.

[ATIS] Page 1

4.1BLOCK DIAGRAM:

[ATIS] Page 2

DATA RECEIVER AND DISPLAY

VHF RECEIVER(AVIATION

BAND)

HEAD SET/SPEAKER

RECEIVER

COMPUTER(TEXT TO SPEECH

CONVERSION)

CONTROLSIGNAL & DATA

CONTROL SIGNAL

AUDIO

STEREO

DIGITAL INFORMATION RS 232

TRANSMITTER

MICRONTROLLER BASED CONTROL

CIRCUIT AND DATA TRANSMITTER

VHF TRANSMITTER(AVIATION BAND)

RS 232WIRELESS

COMMUNICATION

Fig 4.1 block diagram

5.2 POWER SUPPLY:

  

[ATIS] Page 3

AUTOMATIC WEATHER STATION (AWS)

Measured weather parameters

Weather Parameters In digital form

5.3 TRANSMITTER :

[ATIS] Page 4

0

5.4 RECEIVER:

[ATIS] Page 5

FLOW CHART: TRANSMITTER

[ATIS] Page 6

START

SELECT TIMER MODE & SERIAL COMMUNICATION MODE

MAKE Tx BUFFERS ON, Rx BUFFERS OFF & OPTO OFF

MONITOR RxD PIN

IS ‘A’ RECEIVED

?

MAKE Rx BUFFERS ON & OPTO ON

SEND ACKNOWLEDGEMENT LETTER ‘B’ TO PC

MONITOR RxD PIN

IS ‘Y’ RECEIVED

?

SEND ACKNOWLEDGEMENT LETTER ‘Z’ TO PC

NO

YES

NO

YES

RECEIVER

[ATIS] Page 7

START

SELECT TIMER MODE & SERIAL COMMUNICATION MODE

MAKE LCD READY TO DISPLAY

IS ‘@’ RECEIVED

?

STORE DATA RECEIVED AT RxD

IS ‘~’ RECEIVE

D?

DISPLAY MESSAGE “WAITING”

MONITOR RxD PIN

DISPLAY MESSAGE “CONNECTED”

DISPLAY WEATHER PARAMETERS & THEIR RESPECTIVE VALUES ONE BY ONE

NO

YES

NO

YES

[ATIS] Page 8