This disclosure describes methods, apparatus, and systems related to a channel estimation field (CEF) for various standards, for example, the 802.11ay standard, for single carrier (SC) MIMO channel estimation. In one embodiment, the CEF can use Golay complementary sequences. In another embodiment, the Golay complementary sequences can be defined similar to Golay complementary sequences definitions that can be found in various legacy standards, for example, the legacy 802.11ad standard. Various embodiments of the disclosure can allow channel estimation in the time domain and/or frequency domain, having small or negligible inter-stream interference. Various embodiments of the disclosure can enable an extendable structure for various M×N MIMO configurations, where M and N are positive integers.

Aspects of the disclosure relate to channel estimation and tracking in a wireless communication system. A wireless communication entity estimates a received signal utilizing any suitable process. The wireless communication entity applies a Wavelet decomposition filter to the estimated received signal to generate a channel coefficient estimate. The Wavelet decomposition filter may be configured to employ a Haar mother Wavelet. The wireless communication entity generates a prediction of a future channel estimate at a later time, by characterizing the channel according to a first-order autoregressive model of channel aging. Other aspects, embodiments, and features are also claimed and described.

There are provided systems, methods, and interfaces for optimization of the fronthaul interface bandwidth for Radio Access Networks and Cloud Radio Access Networks.

This application provides example channel measurement methods and example communication apparatuses. One example method includes determining L weighting coefficients for determining channels of K moments based on channels of M moments, where L, M, and K are all positive integers. Information about the L weighting coefficients can then be sent.

The invention relates to a method for transmitting at least K reference signals in a radio signal to be transmitted over a wireless communication system, said radio signal being intended to be emitted by an emitter comprising at least a transmit antenna configured for emitting on a number M of subcarriers S.sub.1, . . . , S.sub.M amongst which at least a number K of different subcarriers S.sub.q+1, S.sub.q+2, . . . , S.sub.q+K are contiguous, the respective frequencies of the contiguous subcarriers S.sub.q+1, S.sub.q+2, . . . , S.sub.q+K being ordered, said radio signal being provided by: inserting the at least K reference signals P.sub.1, . . . , P.sub.K so that the at least K reference signals P.sub.1, . . . , P.sub.K are respectively transmitted on the K contiguous subcarriers S.sub.q+1, S.sub.q+2, . . . , S.sub.q+K; emitting the radio signal including the at least K reference signals.

Methods, systems, and devices for wireless communications are described. A base station may identify time and frequency resources for a physical downlink shared channel (PDSCH) to be transmitted to a user equipment (UE) in a first transmission time interval (TTI). The base station may transmit configuration information for a control channel search space set in a second TTI. The second TTI may precede the first TTI. The configuration information may include an indication of an absence of a physical downlink control channel (PDCCH) transmission to send in the control channel search space set indicating the identified time and frequency resources for the PDSCH, and a set of time and frequency resources for the control channel search space set. The UE may receive the configuration information and identify the time and frequency resources allocated for the PDSCH in the second TTI, and receive the PDSCH transmission in the second TTI.

There are provided systems, methods, and interfaces for optimization of the fronthaul interface bandwidth for Radio Access Networks and Cloud Radio Access Networks.

Embodiments of the present disclosure relate to a method, an apparatus and a computer readable storage medium of user selection for MU-MIMO communications. In example embodiments, a method is provided. The method comprises determining a set of candidate terminal devices; and iteratively performing the following at least once until an end condition is met: generating, based on respective channel estimations for the set of candidate terminal devices, a covariance matrix indicating interdependency among the set of candidate terminal devices; determining a minimum eigenvalue of the covariance matrix and an eigenvector corresponding to the minimum eigenvalue, the eigenvector indicating a set of measurements for interdependency among the set of candidate terminal devices; and updating the set of candidate terminal devices by removing, from the set of candidate terminal devices, a candidate terminal device associated with a maximum measurement in the set of measurements.

Aspects of the disclosure relate to channel estimation and tracking in a wireless communication system. A wireless communication entity estimates a received signal utilizing any suitable process. The wireless communication entity applies a Wavelet decomposition filter to the estimated received signal to generate a channel coefficient estimate. The Wavelet decomposition filter may be configured to employ a Haar mother Wavelet. The wireless communication entity generates a prediction of a future channel estimate at a later time, by characterizing the channel according to a first-order autoregressive model of channel aging. Other aspects, embodiments, and features are also claimed and described.

There are provided systems, methods, and interfaces for optimization of the fronthaul interface bandwidth for Radio Access Networks and Cloud Radio Access Networks.