Please give technical suggestion to reduce FER in the network. During drive test we find FER is high. We found that E 1 link connectivity between MSC to BTS is good. what all the reasons which will increase FER in a Network.
FER is the frame erasure rate. Why would a frame be erased? The main reason (in 99.99% of the cases), it is because the frame could not be built from the radio blocks received by the TRX.
in other words: the trx receives radio data from the MS, but the radio link quality is so poor that the TRX can’t read the incoming data. Therefore it can’t built the speech frame –> for this 20ms, the speech frame is “erased”.
The FER is due to interference or bad coverage of your radio network. Interference can be due to “real” interferences (co channel or adj channel), or wrong settings of your frequency hopping parameters.
It sometimes happens that the TRX is faulty, and even though the radio quality is good, the TRX can’t built the frames.
In my eexperience, nothing else can generate high FER only… if a link has a poor quality, it would affect everything (call drops, call setup, ho failure, etc.)