Increased in HSDPA Drops after CS IRAT TURN OFF


Dear Experts,
Recently we have switched Off CS Irat from 3G to 2G from the RNC. We have U2100 and U900. After CS Irat Turn Off U2100 has the facility to do inter freq handover so the compressed mode triggers on cell level are in place -14 and -109. For U900 we put it -24 and -120. But in this process our HSDPA Drops Increased and only on U900. What link even 2d has with the increased number of HSDPA Drops. When we put it back to -14 and 109 for U900 cells the HSDPA Drops are recovered on U900.

Any expert opinions are welcome.