User's Manual

ROCKWELL COLLINS
COMPONENT MAINTENANCE MA NUAL with IPL
TDR-94, PART NO 622-9352
1
2 Extended Squitter Message (ME) Field
The 56 bit ME field is used to transmit extended squitter Automatic Dependent
Sur veillance (ADS) and Aircraft Identification (AI) in DF number 17 messages.
1
3 Message Comm V (MV) Field
The 56 bit MV field contains information used in the air to air exchanges
between mode S transponders and is part of t he long special surveillance reply
using DF number 16. Note that this message field does not follow the
Comm B protocol.
1
4 Number of D Segment (ND) Field
The 4 bit ND field provides the number of the segment transmitted in a
downlink ELM and is par t of t he Comm D reply. It is not implemented in the
TDR-94/94D Class 3A Mode S Transponders.
1
5 Pari ty/Interrogator Identity (PI) Field
The 24 bit PI field contains the parity overlaid on the interrogator identity code.
1
6 Reply I nformation (RI) Field
The 4 bit RI field (used in special surveillance replies DF
numbers 0 and 16) reports the airspeed capability and type of
reply to an interrogating air plane. Codes are defined as follows:
R
I DESCRIPTION
0 No on-board TCAS
1 (Not assigned)
2 On-board TCAS with resolution capability inhibited
3 On-board TCAS with vertical-only resolution capability (TCAS II)
4 On-board TCAS with ver tical and horizontal resolution capability
(TCAS III)
5 - 7 (Not assigned)
8 - 15 Indicates that downlink is an acquisition reply,
further defined as follows:
8 No maximum airspeed data available
9 Airspeed up to 75 knots
10 Airspeed is greater than 75, up to and including 150 knots
11 Airspeed is greater than 150, up to and including 300 knots
12 Airspeed is greater than 300, up to and including 600 knots
13 Airspeed is greater than 600, up to and including 1200 knots
14 Airspeed is greater than 1200 knots
15 (Not assigned)
Bit 14 of this field is the AQ bit of the interrogation.
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May 18/06