1800Mhz layer failure

[dnotembo]

in our network we have the problem on some few sites where there is failure in allocation of TCH in 1800 Mhz layer from 900Mhz as result the call setup is very bad for the whole BSC can any one tell why these failures are happening. the network FLEXI BSC and the problem happened randomly in different area.

[gandhibapu]

may be you need to review the thresholds you have defined for handovers from 900 to 1800 Mhz layer.

[seair]

YOU can increase the parameter "NBL" of 1800MHz BTS in SEG(dual band common BCCH )