| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve system performance, in an OFDM (Orthogonal Frequency Division Multiplexing)-MIMO (Multiple-Input Multiple-Output) system. <P>SOLUTION: A transmitter generates and transmits a low rate signal to its intended receiver. The receiver generates and transmits a CSR (channel sounding response). The CSR is a short burst having a predefined transmit format and carrying predetermined information. The transmitter then analyzes the CSR and determines uplink channel response, estimates downlink channel response, and determines appropriate transmit parameter settings based on the analysis and downlink response estimate. Adjustment of the transmit parameters is made in either an MAC (medium access control) or PHY (physical) layer. After adjusting the transmit parameters and modulating sub-carriers with user-data according to the determined transmit settings, the transmitter transmits the user-data to the receiver on a preferred portion of bandwidth. The transmitter may also generates a transmission format TFC signal including the determined transmit parameter settings, including sub-carrier modulation information. <P>COPYRIGHT: (C)2011,JPO&INPIT |
