| 摘要 |
In a system using spatial precoding, in the event that reliable channel state information is unavailable, a transmitting node uses an extended transmission mode, in which the precoders applied to data within each of several groups of time-frequency resources vary according to frequency. The extended transmission mode creates a frequency-selective variation in precoders, which may appear to be random, while using DMRS-based transmission. This variation is achieved by applying different precoders to the resource elements carrying data, using a pattern of precoder variation that is known to the receiving device. The precoding applied to DMRS within a given group of time-frequency resources is held constant—thus, the varying precoders within a given group of time-frequency resources are only applied to data elements, not to the DMRS resource elements. |
