ATPC Algorithm
ACM can be implemented together with
automatic transmit power control (ATPC)
,
complimentary features that enhance overall system performance. ATPC reduces the average
transmitted power as well as CCI and adjacent-channel interference (ACI), which is caused by
extraneous power from a signal in an adjacent channel. It also enables a more efficient and cost-
effective network frequency plan and deployment, as well as eliminating some of the receivers’
“upfade” problems by changing the transmitted power according to the link momentary conditions.
The lower average Tx power also extends the equipment’s mean time between failures.
ATPC can be used together with ACM to control the transmitted power in any given ACM profile.
Different algorithms can be implemented to achieve maximal spectral efficiency or minimal
transmitted power using both features in combination. One implementation could target maximal
spectral efficacy by trying to reach the highest ACM profile, while the other is willing to compromise
on some of the spectral efficiency enabling CCI and ACI reduction. In any chosen algorithm, ATPC
reduces the average transmitted power, benefiting each ACM profile and any link condition.
The local CFIP PhoeniX receives information (each second) about Rx level from the far-end CFIP
PhoeniX through the service channel; depending on the received Rx level parameter, the local CFIP
PhoeniX adjusts the transmitter power in accordance with the algorithm shown below.
Figure 4.3
ATPC algorithm
CFIP PhoeniX Series TDM/IP Split Mount System Technical Description and Configuration Guide
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Rev. 1.13
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© SAF Tehnika JSC 2015
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