摘要 |
A technique for rapidly and efficiently adjusting characteristics of communication in a time-and-frequency varying channel involves the adaptive selection of a transmission mode (i.e., various kinds of modulation, coding, and antenna combining schemes) and a channelization mode (i.e., the manner in which the spectrum is used during transmission). The method includes determining signal quality estimates [32] from received signals, deriving a set of transmission mode parameters [38] from the estimates, and sending parameters [38] as feedback [40] from a receiver to a transmitter. In one embodiment, each of the transmission mode parameters [38] is a transmission mode selected for use with one of the system channelization modes. In another embodiment, transmission mode parameters [38] comprise one parameter selected for use with any system channelization mode. The method also comprises deriving a set of channelization mode parameters from channel traffic workload information and possibly other information. A single channelization mode [48] is selected from the set of channelization mode parameters, and a single transmission mode [50] is selected from the set of transmission mode parameters. The transmission mode and channelization mode may be selected jointly; or the channelization mode may be selected independently, after which the corresponding transmission mode is selected in dependence upon the selected channelization mode. In the case where only one transmission mode parameter is sent as feedback, the transmission mode selection is trivial and independent of the selected channelization mode. The selected transmission mode and channelization mode are then used for encoding and modulation [54] prior to transmission of information over the communication channel.
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