a ue system implements dynamic link adaptation by adding or changing control information to notify a receiver which timeslots and codes are currently active and which timeslots should be avoided . the ue provides synchronization such that the receiver knows which timeslots and codes the ue has used to map the coded composite transport channel onto physical channels . the ue attempts to avoid the timeslots which are experiencing transmission difficulties , while attempting to utilize the timeslots which are not experiencing transmission problems .