Beam-Change Indication for Channel Estimation Enahncement

摘要

A method of transmitting and receiving a HE PPDU and perform channel estimation enhancement is proposed. The HE PPDU comprises legacy preamble, HE-STF, HE-LTF, and data. A beam-change indication indicates if the pre-multiplied beamforming Q-matrix is changed from legacy preamble to H-SFT, HE-LTF, and data portion. A value of 1 indicates that Q matrix is changed. A value of 0 indicates that Q matrix is unchanged and receiver should be safe to combine L-LTF and HE-LTF. The beam-change indication can be used to significantly enhance channel estimation at receiver. When there is no beam-change, receiver does not change operation during HE-STF and HE-LTF such that the channel estimations can rely on the combination of L-LTFs, L-SIG, RL-SIG, HE-SIGAs and HE-LTF.

主权项

1. A method comprising:
receiving a high efficiency (HE) frame in a wireless communication network by a wireless device, wherein the HE frame comprises a legacy preamble containing a first training field and a HE preamble containing a signal field and a second training field; performing channel estimation based on the first training field and the second training field for a first channel condition and a second channel condition, respectively; decoding a beam-change indicator in the signal field and determining whether there is beam change between the first channel condition and the second channel condition; and performing a channel estimation enhancement by deriving an enhanced channel response matrix based on both the first training field and the second training field if the beam-change indicator indicates no beam change.