This specification provides a method for transmitting, by a user equipment (UE), a CSI (Channel State Information) report in a wireless communication system. More specifically, the method includes: receiving, from a base station, downlink control information (DCI) including information for triggering the CSI report; computing CSI based on the number of symbols related to a time for computing the CSI; and transmitting the CSI report to the base station, in which the number of symbols related to the time for computing the CSI is defined based on information for the number of antenna ports, information for a CSI-RS resource, information for a bandwidth granularity, and information for a CSI codebook type.

Apparatuses, computer readable media, and methods for physical layer short feedback. An apparatus of a high efficiency (HE) station is disclosed. The apparatus comprising circuitry configured to: decode a trigger frame for short feedback, the trigger frame comprising an indication of a resource unit (RU) to respond to a short feedback request, where the RU comprises one or more tones and one or more symbols. The circuitry may be further configured to encode a short feedback response to the short feedback request on the RU, where each of the one or more tones of the RU is to be encoded with one or more of: a positive signal, a negative signal, and no signal. The circuitry may be further configured to configure the HE station to transmit the short feedback response to an access point in accordance with orthogonal frequency division multiple access (OFDMA) using resources of the RU.

To appropriately control CSI reporting even in a case of performing CSI reporting by employing a method different from ones for existing LTE systems, one aspect of a user terminal of the present invention includes a transmitting section that transmits channel state information, and a control section that controls transmission of the channel state information by using certain downlink control information indicating trigger and/or activation of channel state information without scheduling data.

Systems, methods, apparatuses, and computer program products for aperiodic channel state information (CSI) reporting for enhanced carrier aggregation are provided. One method includes transmitting, by a network node, a configuration of at least two aperiodic channel state information (A-CSI) reporting modes per one or more configured downlink (DL) component carriers (CC) to at least one user equipment. The method may also include transmitting an aperiodic channel state information (A-CSI) trigger to the at least one user equipment. The transmitting of the A-CSI trigger may cause the at least one user equipment to dynamically switch between the two configured aperiodic channel state information (A-CSI) reporting modes.

This specification provides a method for transmitting, by a user equipment (UE), a CSI (Channel State Information) report in a wireless communication system. More specifically, the method includes: receiving, from a base station, downlink control information (DCI) including information for triggering the CSI report; computing CSI based on the number of symbols related to a time for computing the CSI; and transmitting the CSI report to the base station, in which the number of symbols related to the time for computing the CSI is defined based on information for the number of antenna ports, information for a CSI-RS resource, information for a bandwidth granularity, and information for a CSI codebook type.

A channel state measurement method and an apparatus are provided. In embodiments of the present invention, a terminal receives CSI reporting mode indication information. The CSI reporting mode indication information is used to instruct the terminal to perform joint CSI measurement and feedback based on N pieces of associated CSI measurement configuration information. Therefore, the terminal may perform CSI measurement and feedback according to the CSI reporting mode indication information, so as to implement CSI measurement and feedback in a scenario in which a plurality of coordinated transmission points perform coordinated transmission.

Method performed by a wireless device (130) operating in a wireless communications network (100) wherein a plurality of beams (121) is transmitted by one or more network nodes (111, 113, 114) in the wireless communications network (100). The wireless device (130) generates (602) a log over a period of time. The log comprises: a) information about a first set of beams (122) in the plurality of beams (121) detected by the wireless device (130), and b) a time of detection. The log comprises the information and the time of detection for both of: i) a first set of time periods when the wireless device (130) was in a connected state in the wireless communications network (100), and ii) a second set of time periods when the wireless device (130) lacked a connection in the wireless communications network (100). The wireless device (130) sends (605) the generated log to a first network node (111).

Methods, apparatus and systems for performing channel measurement in a multi-beam wireless communication are disclosed. In one embodiment, a method performed by a wireless communication node is disclosed. The method comprises: transmitting a channel measurement frame based on a plurality of beams to a wireless communication device through a channel between the wireless communication node and the wireless communication device; and receiving a feedback frame from the wireless communication device. The channel measurement frame comprises a training sequence including a plurality of repetitive segments. Each of the plurality of repetitive segments is transmitted based on a respective one of the plurality of beams. The feedback frame comprises channel information of the channel with respect to at least one beam of the plurality of beams.

A base station includes a memory holding information on P terminals in connecting to the base station, where P is an integer of 3 or more, a determination unit that determines L terminals to transmit a reference symbol used for measurement of channel state information indicating a state of a propagation path to the base station from among the P terminals based on the information on the P terminals, at every data transmission cycle, where L is an integer satisfying 2L<P, a selector that selects M terminals capable of spatial multiplexing communication in the data transmission cycle based on a measurement result of the channel state information based on reception of the reference symbol transmitted from L terminals, where M is an integer satisfying 2ML, and receives respective pieces of data transmitted from the M terminals via a plurality of antennas.

A method performed by a User Equipment(UE) is performed. The UE obtains (202) a beam reporting configuration. The beam reporting configuration defines a beam reporting procedure for determining an optimal beam for each of different sub-bands of a system bandwidth. The UE measures (204) different reference signals transmitted by the network node. The measured different reference signals correspond to each of the different sub-bands according to the beam reporting configuration. The UE then determines (206) a preferred beam for each of the different sub-bands based on the corresponding received reference signals.