FER ( frame Error Rate )

a frame error is defined as a frame that is received with bit errors detected ( a failed CRC check ) or an erasure ( a frame with insufficient quality to make a frame rate determination ).

FER is normally measured y counting onlu full rate frame errors divided by the number of full rate frames. FER should be measured over the period of the typical call, about 100 120 seconds. A common performance FER target for voice would be 1% plus a confidence interval.

FER :

• on forward channel (realized at handset )
• on reverse channel ( realized at base station )
• FER is an excellent call quality " summary " statistic

FER is the end result of the whole transmission link

• if FER is good, the any other problems aren't having much effect
• if FER is bad , that's the problem