PARAMETERIZED CODEBOOK SUBSETS FOR USE WITH PRECODING MIMO TRANSMISSIONS

摘要

One aspect of the teachings presented herein provides advantages for sending precoder selection feedback from a transceiver to another transceiver, for use by the other transceiver as precoding recommendations. The transceiver generates two types of precoder selection feedback, where one type uses a smaller signaling payload than the other and therefore provides a distinct reduction in the signaling overhead associated with reporting precoding recommendations. The transceiver uses the reduced-overhead type of reporting when reporting at certain times, or on certain channels, or in response to control signaling. In one example, a UE in an LTE network sends precoder information to an eNodeB on the PUCCH by sending smaller-range index values that index only a subset of precoders, but sends full-range index values when reporting on the PUSCH, which index a larger set of precoders.

主权项

1. A method in a second wireless communication transceiver of providing precoder selection feedback to a first wireless communication transceiver as precoding information for said first transceiver, said method comprising:
determining channel conditions at the second transceiver; operating in a first feedback mode, selecting a precoder from a predetermined set of precoders based on said channel conditions, sending a full-range index value, with the ability to indicate any of the precoders in the predetermined set, for the selected precoder to said first transceiver as said precoder selection feedback; operating in a second feedback mode, selecting a precoder from a smaller, predetermined subset of precoders contained within the predetermined set of precoders based on said channel conditions, and sending a smaller-range index value, with the ability to only indicate precoders within the predetermined subset of precoders, for the selected precoder to said first transceiver as said precoder selection feedback; and using a smaller signaling payload for sending smaller-range index values as compared to the signaling payload used to send full-range index values.