carrier aggregation improvement

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I deleted thread earlier by mistake so repost.


Description:
The eNB sends a MAC CE to activate the configured SCells when the data volume buffered at the RLC layer exceeds max (Uu data rate at the RLC layer x CaMgtCfg.ActiveBufferDelayThd, CaMgtCfg.ActiveBufferLenThd).
With CaInstantlyJudgeSwitch setting OFF, we keep the ActiveBufferDelayThd as 10ms and change the ActiveBufferLenThd from 6Kbyes to 3Kbytes. And accordingly, change DeactiveBufferLenThd from 3Kbytes to 1Kbytes.
With this optimization, eNB will activate SCC with lower RLC Buffer length. Thus it could achieve more CA traffic volume.

Impact:
This optimization could achieve CA traffic increase with current CA penetration rate. No impact to other KPIs.CA improved considerably.