50 lines
2.2 KiB
Plaintext
50 lines
2.2 KiB
Plaintext
# Handover to cell with worse RXLEV, if RXQUAL is below minimum
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# The neighbor cell has worse RXLEV, so no handover is performed.
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# If the RXQUAL of the current cell drops below minimum acceptable
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# level, the handover is performed. It is also required that 10
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# reports are received, before RXQUAL is checked.
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#
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# (See also test 28, which tests for RXQUAL triggering HO to congested cell.)
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#
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# TODO: bad RXQUAL may want to prefer assignment within the same cell to avoid interference.
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# See Performance Enhancements in a Frequency Hopping GSM Network (Nielsen Wigard 2002), Chapter
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# 2.1.1, "Interference" in the list of triggers on p.157.
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# first show undesired oscillation when penalty-time low-rxqual-ho is disabled
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network
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handover2 penalty-time low-rxqual-ho 0
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create-n-bts 2
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set-ts-use trx 0 0 states * TCH/F - - - - - -
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meas-rep repeat 9 lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30
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expect-no-chan
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meas-rep lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30
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expect-ho from lchan 0 0 1 0 to lchan 1 0 1 0
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expect-ts-use trx 0 0 states * - - - - - - -
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expect-ts-use trx 1 0 states * TCH/F - - - - - -
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# Now the channel is on bts 1, which has lower rxlev than bts 0.
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# The result is an undesired ho oscillation, because the penalty timer is zero
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meas-rep lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40
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expect-ho from lchan 1 0 1 0 to lchan 0 0 1 0
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# Set a proper penalty timeout and report bad-rxqual again
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network
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handover2 penalty-time low-rxqual-ho 10
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meas-rep repeat 10 lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30
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expect-ho from lchan 0 0 1 0 to lchan 1 0 1 0
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# This time the penalty timer prevents oscillation
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meas-rep repeat 10 lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40
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expect-no-chan
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# After the penalty timeout passes, we do go back to the cell with stronger rxlev
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wait 10
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meas-rep lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40
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expect-ho from lchan 1 0 1 0 to lchan 0 0 1 0
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# If the rxqual is still bad here after the penalty timeout, well, then we quickly snap back to the weaker cell, once
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meas-rep repeat 10 lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30
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expect-ho from lchan 0 0 1 0 to lchan 1 0 1 0
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meas-rep repeat 10 lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40
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expect-no-chan
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