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AIM

10/12/17

4

−5−21

Surveillance Systems

4

−5−10. Automatic Dependent

Surveillance

−Rebroadcast (ADS−R)

a. Introduction.

ADS

−R is a datalink translation function of the

ADS

−B ground system required to accommodate the

two separate operating frequencies (978 MHz and
1090 ES). The ADS

−B system receives the ADS−B

messages transmitted on one frequency and ADS

−R

translates and reformats the information for
rebroadcast and use on the other frequency. This
allows ADS

−B In equipped aircraft to see nearby

ADS

−B Out traffic regardless of the operating link of

the other aircraft. Aircraft operating on the same
ADS

−B frequency exchange information directly

and do not require the ADS

−R translation function.

(See FIG 4

−5−8 and FIG 4−5−9.)

b. Reports of ADS

−R Malfunctions.

Users of ADS

−R can provide valuable assistance in

the correction of malfunctions by reporting instances
of undesirable system performance. Since ADS

−R

performance is monitored by maintenance personnel
rather than ATC, report malfunctions to the nearest
Flight Service Station (FSS) facility by radio or
telephone. Reporters should identify:

1.

Condition observed.

2.

Date and time of observation.

3.

Altitude and location of observation.

4.

Type and call sign of the aircraft.

5.

Type and software version of avionics

system.