Advanced Features
English
81
MDC Over-the-Air Rekeying (OTAR) Page
This feature allows to view or define MDC Over-the-Air
Rekeying (OTAR) features.It is applied only when operating in
secure encrypted mode and only for conventional
communications. In additional to Rekey Requests, OTAR
transmissions include Delayed Acknowledgements, and Power-
up Acknowledgements.
Some of the options selected may also need to be set up at the
Key Management Controller (KMC) site to work properly.
Note:
This feature must be preprogrammed by a qualified
radio technician. Check with your dealer or system
administrator for more information.
Infinite UKEK Retention
This feature enables Unique Key Encryption Key (UKEK) to be
permanently stored in the radio even when all of the encryption
keys is erased. Without this UKEK key, the radio could not be
over the air rekeyed.
Note:
This feature must be preprogrammed by a qualified
radio technician. Check with your dealer or system
administrator for more information.
Hear Clear
There are two components of Hear Clear.
1
Companding:
Reduces the channel noise, e.g. OTA transmission, that is
predominantly present in UHF2 and 900 MHz channel with
the following features.
•
Compressor
–
reduces the background noise flow and the
speech signal at transmitting radio.
•
Expander
–
expands the speech while the noise flow
remains the same at receiving radio.
2
Random FM Noise Canceller (Flutter Fighter):
Reduces the unwanted effects of random FM noise pulses
caused by channel fading under high Signal-to-Noise (S/N)
conditions such as in a moving in a transportation. The fading
effects, heard as audio pops and clicks, are cancelled without
affecting the desired audio signal.
The Random FM Noise Canceller operates only in receive
mode.
Note:
This feature must be preprogrammed by a qualified
radio technician. Check with your dealer or system
administrator for more information.
APX_2000_M2_Global.book Page 81 Thursday, May 30, 2013 9:49 PM
