handover decision: if rxlev is ok but rxqual is bad, move to different timeslot with same TCH kind to avoid interference
interference scenario: #3483 is about assigning more "bandwidth" by moving from TCH/H to TCH/F in case of bad rxqual, but it can also make sense to move to a different timeslot of the same TCH kind. I've taken this from the book "Performance Enhancements in a Frequency Hopping GSM Network" (Nielsen,Wigard 2002)
Chapter 8, 2.1.1 Handover in CAPACITY, page 157:
"Interference. When the averaged received signal level (AV-RXLEV) of a certain mobile station is satisfactorily high but the averaged quality (AV-RXQUAL) bad, a handover can be triggered due to interference. Typically, when triggered by the interference ctriteria, an intra-cell handover attempt (handover inside the own cell) is prioritised above an inter-cell attempt (handover between two cells), if frequency hopping is not being used."
It's not entirely clear to me how interference is reduced by moving to a different timeslot, maybe due to another MS close by with timing jittering into neighboring time slots? All I know so far is above quote.