RX diversity loss alarm

SO CF I2A:33 - RX Diversity Lost Description There is an imbalance in signal strength between the receiver paths for one or more TRXs. Depending on which RX path has the lowest signal strength, one or more of the related faults are also raised. To avoid false alarms, the fault has a long filter time that depends on the traffic load. Therefore, the fault can occur several days after installation. Despite the long filter time, a single mobile might cause an alarm if the call is made when the traffic is low and the call continues for a long time in an area with poor coverage, for example, during nights and behind the antenna. When traffic increases, the alarm normally ceases. To correct this kind of alarm, the radio cell planning must be revised. Action Follow the instructions below until the fault is resolved. Note: Long filter time 0 do not use reset until all actions have been performed. Note: If other alarms are raised on the same RX path,this might also be the cause of the RX diversityalarm. If present, then correct such alarms first. • Use the raised RX I2A faults to identify which RXs,and thereby which RX path, are faulty. The RX path identifies the antenna connection to investigate. • Check that cables are connected to the correct antennas. The OMT Radio view shows how the IDB is defined regarding the connections. • Check that the correct RX Diversity mode is defined in the BSC (RX parameter RXD with possible values A, B, AB, and ABCD). See antenna setup in the OMT Radio view for help. • If applicable, check that ALNA/TMAs are working correctly, for example, by monitoring the ALNA/TMA current power consumption with the OMT and comparing it with expected consumption. • Check all radio cables, connectors and other passive radio equipment, for example, with Antenna System VSWR tests. • Check the antennas.