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GSM
potentially uses slow frequency hopping, changing the
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transmission
frequency before every burst
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frequency
diversity improves reception since different frequencies
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are
affected differently during propagation
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interferer
diversity improves reception by distributing relative
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interference
of particular frequency among many calls
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if
operator chooses to employ frequency hopping, sequences
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within
cells and between neighboring cells must be coordinated
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hopping
sequences are sets of (time slot number, frequency) pairs,
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where
frequency is one of up to 64 different frequencies
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n |
Mobile
Allocation Index Offset (MAIO) is a value between (1,
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number
of allocated frequencies in cell)
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n |
Hopping
Sequence Number (HSN) is a value between (0, 63)
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n |
MAIO
and HSN combination determine a pseudo-random
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hopping
sequence
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