Automatic Transmit Power Control and eAlign

ePMP supports Automatic Transmit Power Control (ATPC) where the SMs are instructed by the AP to adjust their Tx power in order for the SM’s signal (UL RSSI) to arrive at the AP at a predetermined RSSI level (configurable on the AP under Configuration->Radio->Power Control->Subscriber Module Target Receive Level).

This feature is beneficial to keep the overall noise floor in the sector to an acceptable level and is critical for deploying a GPS Synchronized system. However, the feature negates the purpose of eAlign measurements on the AP since, during the alignment, the SM may constantly change its Tx power resulting in variance in eAlign readings.

It is recommended to turn off ATPC and set the SM’s Tx power to maximum allowable power during alignment.

While aligning the link using eAlign, please follow these steps:



On the SM, set Configuration->Radio->Power Control->Max Tx Power to Manual


Set Configuration->Radio->Power Control->Transmitter Output Power to 30 dBm (or maximum value allowed by regulations).


Click the Save button


Perform link alignment using eAlign


Once alignment is complete, set Configuration->Radio->Power Control->Max Tx Power back to Auto


Click the Save button

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