Pulse or digital communications – Spread spectrum – Frequency hopping
Patent
1998-01-29
2000-10-03
Chin, Stephen
Pulse or digital communications
Spread spectrum
Frequency hopping
370343, 455450, H04L 2730, H04K 100
Patent
active
061283274
ABSTRACT:
A system and method in a wireless communications system enables a preferred frequency hopping (FH) sequence to be determined and instituted in real-time. The average speed of mobile stations within a cell is determined or estimated using a variety of techniques. If the average speed is below a predetermined threshold, then a cyclic FH sequence is instituted to achieve superior frequency diversity and therefore combat small-scale fading dips. If the average speed is above a predetermined threshold, then a random FH sequence is instituted to achieve superior interference averaging and therefore combat co-channel interference. Delay timers and a hysteresis may also be used to enhance stability and to counteract short-term fluctuations. The measuring of the average speed and the comparing of the average speed to the threshold are periodically repeated.
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Frequency Hopping, CMS 40 System Feature Description, Ericsson Inc. (Jul. 25, 1997), pp. 1-26.
Bird William Eric
Triggs Alan
Chin Stephen
Deppe Betsy L.
Ericsson Inc.
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