Multiplex communications – Generalized orthogonal or special mathematical techniques – Particular set of orthogonal functions
Reexamination Certificate
2004-08-25
2008-11-25
Chan, Wing F (Department: 2619)
Multiplex communications
Generalized orthogonal or special mathematical techniques
Particular set of orthogonal functions
C370S491000, C375S135000
Reexamination Certificate
active
07457231
ABSTRACT:
To allow a receiving entity to derive a longer channel estimate while limiting overhead, a transmitting entity transmits a pilot on different groups of subbands in different time intervals. N subbands in the system are arranged into M non-overlapping groups. Each group includes P=N/M subbands that are uniformly distributed across the N subbands. The transmitting entity transmits the pilot on a different subband group in each time interval, and selects all M subband groups in M time intervals based on a pilot staggering pattern. The receiving entity derives (1) an initial impulse response estimate with P channel taps based on the pilot received on one subband group and (2) two longer impulse response estimates with different lengths used for data detection and time tracking. Each longer impulse response estimate may be derived by filtering initial impulse response estimates for a sufficient number of subband groups using a time-domain filter.
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Mantravadi Ashok
Mukkavilli Krishna Kiran
Vijayan Rajiv
Braden Stanton C.
Chan Wing F
Minhas Sandip S.
QUALCOMM Incorporated
Roberts Brian
LandOfFree
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